Now as far as upgrades. I need to drop about 5 pounds off this tandem, along with the 15-17 pounds that the stoker and I will drop by this spring. That should put as at a great weight to train for The Assault on Marion this upcoming June. I will probably build my own wheels and I am thinking that is probably the place where a large chunk of the weight will come from. If I do some judicious eBaying, I could probably get most of the stuff I need and save some money too.
Looks like It will be DT 540 Tandem Disk hubset, Velocity Deep-V non-machined rims, DT or Wheelsmith 14-15-14g DB spokes w/brass nipples. 36H front/rear in a 3x rear 2x front pattern. With 36 spoke wheels straight 14g spokes just seem like overkill. Will most likely replace the crankset, I have never liked the way the Truvativ Elita shifted. It seems as if you have to ease up excessively to get it to shift smoothly (maybe I am spoiled by the DA drivetrain on my single bike). Other little things to help get the weight down would be helpful, I am willing to take suggestions. The one thing that can't go is the rear drop bars. Bittersweet did not like the bullhorns at all, plus they are now going to go on an upcoming fixed gear project bike.
The BikeForums Team
-adv-
This is an archived thread, you can find the full version of this thread, with images, links and more content here.
1. If you want to get rid of as much weight as possible, consider switching out the front fork for a 1.125" Reynolds Ouzo Pro Tandem with a DuraAce or Ultegra Caliper. It's got an extra .2mm of rake (5.5 vs. 5.3) which, if you like the way your C'dale handles, won't change it all that much.
2. Before jumping to the DT hubs, give White Industries hubs a look: lower cost, lower weight, higher reliability (at least IMHO). Moreover, if you change out the fork you can cut your front hub in half.
3. Cranks aren't inexpensive if you're looking for superlight. Best bet if you want to save a few bucks is to search out a set of Ultegra tandem cranks: big bang for the buck.
4. Not sure what C'dale has spec'd for seatposts and handlebars, but if you think there are some weight savings opportunities there and can resist the lure of carbon consider Thomson's Elite or Masterpiece aluminum posts and SL-grade aluminum handlebars from Deda (e.g., 215) or others.
That's about it, aside from lighterweight tires vs. the stokers.
RickinFl
14 gauge spokes are not overkill- they will give you extra lateral stiffness in your wheels that you will appreciate, especially when doing out of the saddle work such as climbing or sprinting. It makes a difference, more so on tandems than on singles. People that build wheels will tell you that you can build a better wheel with double butted spokes, but the truth is that it's easier to build a wheel with double butted than with heavier straight gauge- it's easier to tension and true a wheel done with DB spokes because they stretch more easily than SG spokes, which is exactly the reason that a wheel done with SG spokes is more laterally stiff.
Hah- I'm ranting already and no one has even had the opportunity to refute me yet :p I'll save the rest of this argument for when someone jumps in to tell me I'm wrong.
One other thing- the weight savings of DB over SG is negligible, especially on a tandem. Far and away the most practical way to reduce the weight of the system is to lose weight from your body if possible. My wife and I have lost 30lbs between the two of us in the last six months (we're a 280lb team now) and the difference is stunning both when accelerating and when climbing.
Rick the Curmudgeon
TandemGeek
Far and away the most practical way to reduce the weight of the system is to lose weight from your body if possible.
... also the least expensive, most effective, but sometimes the most difficult to achieve.
My wife and I have lost 30lbs between the two of us in the last six months (we're a 280lb team now) and the difference is stunning both when accelerating and when climbing.
Cranky!! You and Terri were impossible to hang with BEFORE... Guess we'll have to start training now just so we'll be able to visit with you two for a few miles before being dropped at next year's GTR down in Albany.
zonatandem
Agree most effective way to loose weight off the tandem is for the duo to push away from the table; if you undulge: lay off the beers/booze, sugar coated stuff and yes, even skip dessert (most of the time)!
This captain loves desserts/sweets, however standing order is dessert (maybe!) every other day.
This coming from a guy that, in his younger years, after a century, could go to an all you can eat place, and held the record for only having 7 desserts! One time eating 3 full banana splits (with all the goop and nuts and cherries and stuff) after dinner . . . with the owner of the restaurant offering the 4th split free . . . asked him to give me a raincheck on that. My riding weight then was a 118 lbs.
Thirty-some years later he's 'balooned out' to 135 lbs; stoker's weight is 108 compared to her 98 lbs 53 years ago. Now we order 'senior portions' and have trouble cleaning our plate!
Lighten up the bike: C/f fork and very light (rotating weight!) wheels will make a difference.
Fork suggestion: either Reynolds or Alpha Q tandem fork.
Wheels: Topolino tandem wheelset (c/f spokes with kevlar coating) or Rolf Vigor Tandem set.
For a bit more comfort: c/f handlebars and stoker stem/seatposts.
We utilize Dura Ace calipher on front and Tektro Mini-V on rear for brake.
BTW a real good looking tandem duo (but do suggest captain tighten helmet strap a bit)!
Pedal on TWOgether!
Rudy and Kay/zonatandem
WheresWaldo
Ah, here's the rub. Because of previous life style and not taking care of my body in the past, I am down to pretty much the lowest weight I can get to. December 2005 = 350 pounds, today = 202 pounds. According to my surgeon, I have about 5-10 pounds maximum that I can lose. Now the other alternative is surgery, with that the estimate is an additional 15 pounds over what I mentioned above, but it is painful, has a long recovery period, and my insurance carrier considers it entirely cosmetic. So although I appreciate the comments about losing weight on the body, and I have made them myself to others, it is just not practical.
I do not drink beer, eat sweets or any kind of dessert for that matter. I am just a fairly big person. So summing it up:
Wheels: I will look at the WI hubs, I have a set of Nimble Fly Carbon wheels for my single using WI H1 (no longer available as he now brought out the H2 hubs) and CX-Rays. As these will be event only wheels I might be able to get away with 32h also. I will look at the Rolf's, funny thing Rolf's get no love over on the Road Cycling forum. I'll look at the Topos also.
Fork: We do absolutely zero miles with anything on the bike other than ourselves, no loaded touring or anything more than a two hour ride. Of course that will change when we start training for Metric Centuries. I suppose then that I could ditch the front disk and go with some cantilevers instead, that would allow me to swap out to a carbon fork. Is that correct?
Seatpost: I have Thomson seatposts on both my daughter's and my single bikes, love them, fairly light, strong and would work with the tandem. I will need setback posts both front and rear, hmm. I am not a big carbon seatpost fan, not light, too much cash, I just don't get it.
Saddles: We had Terry saddles (Fly & Butterfly) on there originally, now with many miles we have found them to be too soft, and very uncomfortable after any amount of time in the saddle. I swapped mine out for a Specialized Toupe and Stoker is getting another Selle San Marco Aspide Glamour, maginally lighter but infinitely more comfortable.
Stem: Already have a Thomson in the front, I have never seen a CF stoker stem, can you point me to one.
Bars: Already fairly light AL bars, can't see saving much weight on bars unless I buy two more Zipp bars (already have on on my single). Can't see spending money like that.
Spokes: With the wider bracing angle I don't see any advantage to 14g spokes over a DB spoke as far as lateral stiffness is concerned. There is such a thing as stiff enough, and I think this is one of those times, sorry to disagree with you Rick.
Crank: Probably not a great place to save weight, more likely I can make a profound change in shifting performance by changing out the chainrings to something with better engineered ramps and pins.
Helmet: I was thinking about removing the straps completely just to save those few extra grams!
moleman76
I was thinking about removing the straps completely just to save those few extra grams!
Maybe something with magnets to hold it on.
Fill the bottles with dehydrated water, much less weight.
TandemGeek
I will look at the Rolf's, funny thing Rolf's get no love over on the Road Cycling forum. I'll look at the Topos also.
I'm actually in the wheel market as well and, FWIW, I'm still struggling with anything other than conventional wheels for everyday use, e.g., White Ind. with either Fusion or Deep-Vs. I've looked at the Topolinos (thanks, but no thanks) and am considering the Rolfs as a second set of wheels just for sh*ts and giggles, aka. beta testing. I'm still not convinced that the juice is worth the squeeze long-term on these wheelsets beyond special events. Yes, all indications are that they do make it feel a bit it easier to go the same speed which is essentially what happens when you log base miles on racing equipment. Less I digress further, I'm waiting to hear a first hand report on the new '08 Rolfs from my 'source' who has not yet received the first shipment. They purportedly use a 30mm deep section vs. 33mm and there are some other changes, most likely further weight reductions to keep up with the Joneses. Again, my back-of-the-envelope math suggests that certain White Ind. hubs with sub 500g rims and DB spokes will get you a set of wheels that are in the same weight-range as the Rolfs, but lack the aero advantage.
I suppose then that I could ditch the front disk and go with some cantilevers instead, that would allow me to swap out to a carbon fork. Is that correct?
Yes, there are some 1.125" carbon forks out there with cantilever brake bosses. If you could find one, the Alpha Q CX tandem fork made for Burley would probably be a pretty good option w/48mm of rake. Chucksbikes.com sells something that looks like the cantilever carbon fork made for Santana but with a 1.125" steerer and I have no idea what the rake or fork length is. I would assume it to be 55mm and 395mm, respectively but you'd need to ask. In the caliper-brake department -- which would be my druthers -- the aforementioned Reynolds fork would be my pick of the litter. I would not recommend the Alpha Q X2 unless you're really unhappy with the handling of your Cannondale and won't mind giving up some crank clearance. The Alpha Q X2 has 44mm of rake and is at least 2.6cm shorter than the fork you have on that bike: it will alter the geometry of your bike, to include your riding positions as the front end will drop ~2.6cm and make all of the effective head & seat tube angles steeper. Hey, maybe you won't need those set-back seatposts after all! Seriously, you'd really need to give the X2 fork choice a lot of deep thought. While it could make your C'dale handle more to your liking, it could also make it a handful. Wound-Up also offers a cantilever carbon fork with 45mm of rake and it would fall into the same ballpark as the X2: it might work fine, then again, it might not be to your liking.
I am not a big carbon seatpost fan, not light, too much cash, I just don't get it.
#1: They look really cool. #2: They're lighter than some of the other posts. #3: They look really cool.
Selle San Marco Aspide Glamour, maginally lighter but infinitely more comfortable.
Do you really need the saddles? Just kidding.
I have never seen a CF stoker stem, can you point me to one.
Hold on to your wallet: http://stealthcycling.com/c=Sn6P3w56ySsJ9HqOxXWxaYzzi/category/stems/
Yo, Rudy... Is Bob still making these? I thought he discontinued these along with the AriZona frames?
Crank: Probably not a great place to save weight,
You might be surprised... I don't know what cranks they stuck on the C'dales, but there is something to be said for a well-engineered set of lightweight, super-stiff cranks.
Helmet: I was thinking about removing the straps completely
Helmets are way over-rated: they only work when you crash and, well, how often is that? (Just kidding, again).
RickinFl
Permit me to digress. I realize that this thread has tipped heavily in the direction of grams-shaving, but I'll bore everyone that bothers to read this post a bit more with a curmudgeonly discussion of lateral wheel stiffness.
On a tandem, more lateral stiffness is better, and I'm not sure that you can have too much. The side to side forces operating on tandems are much more than a single bike, and it can be felt. You might interpret a laterally soft rear wheel as something else- a whippy frame, a soft rear tire, or whatever. If you value crisp, precise handling and response, stiffer is better. It's no mistake that sprinters prefer the laterally stiffest wheels that they can find.
A couple of scholarly works that touch on lateral stiffness can be found at:
Gavin's paper is a forest of complex math (which I don't pretend to comprehend), but the interesting thing for us curmudgeons are the two graphs that relate lateral wheel stiffness to spoke diameter and spoking pattern. In all cases, the 14G spoke provides the most laterally stiff wheel. Interestingly, a 2X pattern gives the most torsional compliance in the plane of the wheel (that's the flex you get under braking or acceleration), and some folks feel like that is a good thing- it gives a more comfortable ride. I'll stick to a 3X pattern for my tandem wheels myself.
If you're searching out bling, definitely go for the exotic wheels with only a few spokes. 14G spokes do not have that degree of coolth. If you're looking for performance and sharp handling, stay with conventional wheels built with 14G spokes (I've veered over into personal opinion here....). Given the large forces operating on tandems, especially at the rear wheel, it's smart to prefer strength and reliability over light weight. Lose the weight somewhere else.
I've actually done the work in the real world, having built and tested wheels done both ways, and the difference is anything but subtle. On the other hand, I've been told by Jobst Brandt (among more than a few others) that I'm wrong. So there you have it.
Rick
RickinFl
Ooops- forgot to mention- see you in Albany TG. :)
Rick
bikeriderdave
What does the bike weigh now? How did you pick your five pound target? Have you considered selling the 'Dale and replacing it with a bike that has a lighter frame (C'Dale frames aren't reputed to be especially light, and moving to caliper brakes would be an easy way to shed grams)? Your contemplated upgrades (wheel$, crank$, fork$) could set you back as far as the cost delta for an entirely new bike... and in the end you'd still have the original sturdy-but-flabby frame.
... just a thought!
swc7916
I also don't understand the 5-pound target. Aside from dropping weight from the team, lightening up the wheels would probably give you the most bang for the buck. I don't know how much the disk brakes weigh, but I woulld ditch them for calipers or cantilevers.
It always amuses me how that people will spend big money to drop a few ounces from their bike and then add two (or four) full water bottles that must weigh a couple of pounds! Making sure that your bike fits properly will also make you more efficient and add speed.
WheresWaldo
to Rick,
Wow, if Jobst Brandt told you you are mistaken and you are not sure whether to believe him...
I also think that we, as paired riders, tend to over engineer. Look at the trend in single bikes, with regard to wheels. It seems that lighter, less and thinner spokes is the norm even for big sprinters on the pro circuit. Now I surely do not believe my daughter and I put out that kind of power.
Bling for blings sake is a fools errand. I am not looking for a better looking bike, I am looking for practical ways to improve the performance. We are already working on the engines, and very hard mind you. My daughter has me doing core exercises, and she still laughs at me since I can only do about half the reps she can. I am planning on riding fixed all winter, can you say "big quads." As well as the fact that we do a lot of single bike riding. I am still not convinced 14g spokes is a necessary component in lateral stiffness (< that last remark sounds like every bike review for the past few years, "laterally stiff, yet vertically compliant").
to TG,
I emailed Chucks about the specs on the CX/Tandem fork, I will post his reply. I can't believe CDale uses such an odd sized fork. I did a rough measurement and came out with 410mm crown to center of dropout and I could not really get a good offset measurement, but by eye it did not look like it was over 50mm. I may just take the damn thing apart so I can get better specs. Maybe I should just be smart about it and email CDale first?
to BRD,
I had the measurement somewhere in some spreadsheet, but I can't find it at the moment. I guess I'll have to recharge some NiMH and put them in the Alpine scale and measure it again, I will let you know. BTW, I pulled that figure completely out of the air, not really :)
Not sure I want to outlay that kind of cash all in one lump sum, especially on a bike that is only ridden one day a week! Typically it goes like this, Monday-Friday approximately 1 hour each day on the single bike with my neighbor. Usually hills, one recovery ride, one tempo ride. Saturday is a day off. Sunday morning I ride 50-60 miles with the B group, usually about 2000' vertical climbing, between 18-19 mph overall average. Then I take a nap (the most important part of the day). Two hours latter, we go out on the tandem anything from 15-35 miles depending on the route everyone else wants to go and whether or not we try to hammer the group (they are all single riders). Spreading out the cost is a big deal to the significant other that is not a cyclist!
TandemGeek
Carbon fork = ~$500
Caliper Brake = ~$100
New Wheelset = ~$450 - $600 (Rolf's @ $950, Topolinos @ $1,200: neither are user servicable)
New Crankset = ~$500
New Bits & Pieces = ~$400
It all adds up... however, in reading the OP's postings he's obviously dropped a few bucks on bikes and components over the years and should have a full appreciation for what the costs of an upgrade would be.
TandemGeek
I can't believe CDale uses such an odd sized fork. I did a rough measurement and came out with 410mm crown to center of dropout and I could not really get a good offset measurement, but by eye it did not look like it was over 50mm. I may just take the damn thing apart so I can get better specs. Maybe I should just be smart about it and email CDale first?
Or just look it up on the geometry tables that they provide on their Website:
http://www.cannondale.com/bikes/06/geo-30.html
WheresWaldo
I also don't understand the 5-pound target. Aside from dropping weight from the team, lightening up the wheels would probably give you the most bang for the buck. I don't know how much the disk brakes weigh, but I woulld ditch them for calipers or cantilevers.
It always amuses me how that people will spend big money to drop a few ounces from their bike and then add two (or four) full water bottles that must weigh a couple of pounds! Making sure that your bike fits properly will also make you more efficient and add speed.
Since I really can't drop much more weight from the engine, you have got to start somewhere. Water is water, it weighs the same no matter where it is, in you or on you (a pint a pound the world around). Can't ride without it so it is fixed into the equation. You know what else, you are going to carry that water with you whether or not the bike weighs 40 pounds or 35 pounds.
Bike fits, and has basically the same setup as our single bikes with the exception of captain saddle to bar drop. Saddle to center of cranks are exact, setback is exact, saddle to bar is exact, can't get much closer than that. I could flip the stem and get more aero but it is certainly easier to control the bike sitting just a little more upright!
The disks are heavy, about 120g per caliber and an additional 220g per rotor, that is without bolts, brackets or pads. I could go to some canti's and be down in the 160-180g range with everything for just a few dollars on ebay.
WheresWaldo
Or just look it up on the geometry tables that they provide on their Website:
http://www.cannondale.com/bikes/06/geo-30.html
I guess that would be too easy :D
WheresWaldo
Carbon fork = ~$500
Caliper Brake = ~$100
New Wheelset = ~$450 - $600 (Rolf's @ $950, Topolinos @ $1,200: neither are user servicable)
New Crankset = ~$500
New Bits & Pieces = ~$400
It all adds up... however, in reading the OP's postings he's obviously dropped a few bucks on bikes and components over the years and should have a full appreciation for what the costs of an upgrade would be.
Thanks for this info. I would probably build my own wheels, Fusion or Deep-V rims are about the same price 50-60 each, spokes/nipples under $1 each. Hubs is where the expense is!
That fork is killer.
Moving away from stock tires to a typical 700C x 25 race type tire could save almost 1/2 pound, just there alone. Front wheel with rotor weighs 1520g, please note that is not the pair, it is just the front wheel! Hubs spokes rims could save significantly here. Maybe I can't get 5 pounds off the bike, but I think I can get close without breaking the bank.
I am going out for my daily mid day ride, I will return in about 1.5 hours. by then we should have some more to discuss. You guys in the Tandem forum are great, we can have differences of opinions and still be social and helpful, much more refined than many in the Road forum. Thanks so far.
RickinFl
WheresWaldo-
Actually, what Jobst said was that spoke gauge made no difference in lateral wheel stiffness as long as the wheel is properly tensioned. That contention is clearly contradicted by HP Gavin's research (you did take a look at that, right?). Rikard Gothall also states it concisely- lateral wheel stiffness is a function of (among other things such as flange height and spacing) total spoke cross section for a given spoke number. This all falls into line with what I know from actual experience on the bike, so I'm entertaining the possibility that Jobst might have been, ahem, mistaken. Or at least didn't have the benefit of access to the more modern research I've cited. Anyone that wants to dig back years and years into Tandem@hobbes could probably find that discussion.
By the way, I've ridden a Cannondale tandem for the past 15 years (same color as yours; everyone knows that those Galaxy Blue ones are the fastest<G>), and they are eminently upgradeable as you are doing. It's a great frame, not the lightest, but very stiff and efficient. I've been bitten by the "buy a better tandem" bug many times over the years, and have test driven a lot of fancy bikes. I just haven't found one that works so much better than the Cannondale that the expediture of the $$$$$ seemed worthwhile. My blind stoker (and wife) tends to be quite sensitive to the way bikes feel, and she quite agrees- the big name brands we have tested struck her as way too flexible, especially when climbing.
Have fun with your upgrades, and good luck with your training program.
Rick
swc7916
Since I really can't drop much more weight from the engine, you have got to start somewhere. Water is water, it weighs the same no matter where it is, in you or on you (a pint a pound the world around). Can't ride without it so it is fixed into the equation. You know what else, you are going to carry that water with you whether or not the bike weighs 40 pounds or 35 pounds.
You're absolutely right - you're going to carry the water, but I find it amusing anyway.
Bike fits, and has basically the same setup as our single bikes with the exception of captain saddle to bar drop. Saddle to center of cranks are exact, setback is exact, saddle to bar is exact, can't get much closer than that. I could flip the stem and get more aero but it is certainly easier to control the bike sitting just a little more upright!
Proper bike fit is just now getting the attention that it deserves. Proper fitting will make you more comfortable and efficient - and therefore faster. I just had a fitting for a new road bike and found that I need a custom frame because all of the stock frames have top tubes that are too long for me. I never knew. I had been going by old Fit Kit recommendations that advised a longer reach than my new fitting. All these years I have been riding bikes that didn't fit me because I thought that you were supposed to be stretched out on the bike. When you are younger you can better tolerate an improper fit, but as we age, these things become a bigger issue. Anyway, our new tandem fits me better than any of my previous bikes and I can't wait to get my new single.
TandemGeek
Proper bike fit is just now getting the attention that it deserves.
Are you referring to your personal epiphany, tandem teams as a group, or the rest of the cycling world?
TandemGeek
Front wheel with rotor weighs 1520g, please note that is not the pair, it is just the front wheel!
Food for thought... Here's what's on our Erickson road tandem:
100 gram 36h White Industries Racer-X front hub (aka., M15) laced 3x using 14/15 DB spokes to a Velocity Deep-V rim with rim strip tape = 995 grams or 1,398 grams with a 700x25c tire & tube + skewer. Rear is also a Racer-X so add 206 grams to either number.
For reference purposes, my Campy Eurus front wheel weighs in at 715 grams: 1,138 with 700x23c tire & tube + skewer.
WheresWaldo
You're absolutely right - you're going to carry the water, but I find it amusing anyway.
Proper bike fit is just now getting the attention that it deserves. Proper fitting will make you more comfortable and efficient - and therefore faster. I just had a fitting for a new road bike and found that I need a custom frame because all of the stock frames have top tubes that are too long for me. I never knew. I had been going by old Fit Kit recommendations that advised a longer reach than my new fitting. All these years I have been riding bikes that didn't fit me because I thought that you were supposed to be stretched out on the bike. When you are younger you can better tolerate an improper fit, but as we age, these things become a bigger issue. Anyway, our new tandem fits me better than any of my previous bikes and I can't wait to get my new single.
As a racer and bike mechanic in a former life, I am well aware of bike fit. I am very comfortable with the fit now, I can ride 1 hour or 10 hours (my time for Mt Mitchell) with no discomfort and at a fairly brisk pace for an old guy (although I luckily just miss qualifying for the 50+ forum). I am glad you found a tandem that fits you, I am confident that mine fits me and my stoker/daughter.
Now where can I find some of that dehydrated water for my bottles http://www.comicguide.net/images/smilies/lol2.gif
TandemGeek
Now where can I find some of that dehydrated water for my bottles http://www.comicguide.net/images/smilies/lol2.gif
Right here: http://buydehydratedwater.com/shop/index.php?main_page=index&cPath=1&zenid=cea08a42ce30868308a3415fbd2cf74f
WheresWaldo
WheresWaldo-
Actually, what Jobst said was that spoke gauge made no difference in lateral wheel stiffness as long as the wheel is properly tensioned.
I have read much of what Mr Brandt has written and I tend to agree with most of it.
That contention is clearly contradicted by HP Gavin's research (you did take a look at that, right?). Rikard Gothall also states it concisely- lateral wheel stiffness is a function of (among other things such as flange height and spacing) total spoke cross section for a given spoke number. This all falls into line with what I know from actual experience on the bike, so I'm entertaining the possibility that Jobst might have been, ahem, mistaken. Or at least didn't have the benefit of access to the more modern research I've cited. Anyone that wants to dig back years and years into Tandem@hobbes could probably find that discussion.
My head hurts!http://www.unixboard.de/vb3/images/smilies/sm-nachdenk.gif
By the way, I've ridden a Cannondale tandem for the past 15 years (same color as yours; everyone knows that those Galaxy Blue ones are the fastest<G>), and they are eminently upgradeable as you are doing. It's a great frame, not the lightest, but very stiff and efficient.
http://img84.echo.cx/img84/4866/agreed8mv.gif 100%
I've been bitten by the "buy a better tandem" bug many times over the years, and have test driven a lot of fancy bikes. I just haven't found one that works so much better than the Cannondale that the expediture of the $$$$$ seemed worthwhile. My blind stoker (and wife) tends to be quite sensitive to the way bikes feel, and she quite agrees- the big name brands we have tested struck her as way too flexible, especially when climbing.
Have fun with your upgrades, and good luck with your training program.
Rick
I have a wife and mother of my child that thinks any expenditure on bikes beyond the initial purchase needs the full consent of Congress and the Presidents signature. I highly doubt I could tell her I want to upgrade to a new tandem.http://www.istorya.net/forums/Smileys/alive/sad.gif
WheresWaldo
Food for thought... Here's what's on our Erickson road tandem:
100 gram 36h White Industries Racer-X front hub (aka., M15) laced 3x using 14/15 DB spokes to a Velocity Deep-V rim with rim strip tape = 995 grams or 1,398 grams with a 700x25c tire & tube + skewer. Rear is also a Racer-X so add 206 grams to either number.
For reference purposes, my Campy Eurus front wheel weighs in at 715 grams: 1,138 with 700x23c tire & tube + skewer.
I should have mentioned that the 1520g was without tire and tube. 1980g total weight of front wheel. As a point of reference my tubulars on my single bike weigh 571g Front 734g Rear w/o skewers.
http://img.photobucket.com/albums/v647/bhmmrtn/Bicycles/Triela/th_NimbleRearWeight.jpg (http://img.photobucket.com/albums/v647/bhmmrtn/Bicycles/Triela/NimbleRearWeight.jpg) http://img.photobucket.com/albums/v647/bhmmrtn/Bicycles/Triela/th_NimbleFrontWeight.jpg (http://img.photobucket.com/albums/v647/bhmmrtn/Bicycles/Triela/NimbleFrontWeight.jpg)
Click image for high resolution picture
WheresWaldo
Since many have asked me via PM. The surgery I was referring to is a circumferential body lift. I had GBP in January of 2006 and that was incredibly successful in giving me my life back, I would do it again in a heartbeat. The CBL would remove all the excess skin around the abdomen and the remaining skin would be stretched and then sewn together. Some fatty deposits are also liposuctioned out to contour your body shape. Estimated weight loss from this procedure, in my case, would be 15 pounds.
swc7916
Are you referring to your personal epiphany, tandem teams as a group, or the rest of the cycling world?
Actually, all three. Maybe your experiences are different than mine as I am a recreational rider and have never raced or worked as a bicycle mechanic.
I have seen all kinds of fit criteria - including straddling the top tube, seeing if the handlebars hide the front hub when riding, placing your elbow on the saddle nose and seeing if your middle finger reaches the stem, etc. - but none of these methods gave me a proper fit. In the 80's the Fit Kit was the newest most scientific thing going, but even it didn't recommend a comfortable fit. The shop I go to has been building custom bikes for over 30 years and has compiled their own fit data and uses this fit bike to ensure that you are comfortable on your new bike:
WheresWaldo
TG, now that I am looking at those pretty Nimble Fly wheels I am beginning to wonder if they would be strong enough for a tandem team. The regular FLY rims have been tested to and can support a 650 pound static load unlaced. They make a Clydedale rim called the HorseFly, only 340g per rim. I wonder if they can be built with high enough tension to support a 330 pound team + bike weight. I know that they typically build with between 100 and 110 Kgf, as a reference Velocity builds all their wheels to 120 Kgf (I know, I asked them).
WheresWaldo
Can we play a math game. I am going to try to figure out how a shorter fork will affect the geometry of the bike. First off, I believe the Cdale fork is 410mm in length from fork crown to center of dropouts, most aftermarket forks are 360 - 370mm or so. the difference in the head tube angle should be the following:
arcsin ((old length - new length)/(wheel base))
using the extremes we should have a range.
arcsin((410-360)/171.7)=0.026822
arcsin((410-370)/171.7)=0.025522I was suprised by how small these numbers are, but then remembered that tandems have a long wheelbase and that would tend to reduce the impact of a change in fork length.
So my question is, even if I get a smaller fork and increase the head tube angle by .03° if the trail is the same does the handling become severly impacted by the shorter/lower front end?
WheresWaldo
I know the Cdale site says the trail is 5.1 but the actual measurements and formula for trail do not indicate it is that number. The front wheel has an outside diameter of 685mm the head tube angle is 73° and the fork offset if 53mm. The math comes out to 4.9cm of trail. Please note that fork length is not a direct factor in trail.
Also adding .03° to the head tube angle is insignificant with regard to trail, and most likely less than the manufacturing tolerance. So my question is, has anyone done the swap and noticed a significant difference in the handling of the bike? The numbers would say there shouldn't be, but is there some anecdotal evidence that says otherwise?
TandemGeek
Actually, all three. Maybe your experiences are different than mine as I am a recreational rider and have never raced or worked as a bicycle mechanic.
That's why I asked...
It's an unfortunately truth that proper fit is often times never addressed except for those who are engaged in competitive pursuits or are enthusiasts who take it upon themselves to either search out a qualified bike fitter or learn the various benchmarks and techniques needed to establish efficient riding positions, with emphasis on the "S" as there are can be different "fits" for different types of bikes, events, or the time of year.
Most recreational cyclists are never properly fitted which, when combined with zero instruction on proper technique and use of gearing, contributes to many short-lived cycling interests.
Tandem buyers are also at a disadvantage in that tandems are "nominally" designed and sized for the captain's riding position, and a one-size-fits-all approach is then used for the stoker. There are other 'issues' but they're covered in previous posts that reside in the archives.
Good to hear you've been able to find a fit that works for you.
You are allowed to lurk at the 50+ forum prior to reaching the qualifying birthday. You don't know what you are missing. :lol: Bring your own ibuprofen.
TandemGeek
I wonder if they can be built with high enough tension to support a 330 pound team + bike weight. I know that they typically build with between 100 and 110 Kgf, as a reference Velocity builds all their wheels to 120 Kgf (I know, I asked them).
From Nimble's Website: Horse FLY is nominally rated to 250 lb riders (see weight limits for details). The lateral stiffness is 25 to 40% greater than already stiff standard FLY models. It is offered in 650C and 700C models with tubular style rims. Tubulars are excellent for strength, toughness and performance (see tubular tire advice). Call us for specific tire recommendations.
Can we play a math game.
No, we can't.
You asked for recommendations, I've shared with you what I'm aware of in terms of available products and offered some comments on how those products will compare with what you presently have. The Alpha Q X2 is the only real odd-ball in the bunch when it comes to the tandem-rated carbon forks in that the Reynolds uses a 395mm fork length because that's what Santana spec'd for their tandems. Wound-Up uses 387mm because that's what Co-Motion spec'd. The Alpha Q CX tandem used 395mm which is a common cyclocross length and the X2 is just really short @ 374mm... single road bike length, if you will.
In the tandem steering trail spectrum where almost all of the tandems have 73 degree head tubes, your Cannondale's steering geometry is more like Santana's and Trek's (and also Burley's when they were still making tandems) than it is anything else. Going from memory...
Bilenky @ 57mm of rake with 73.5* headtube
Santana, Trek, Burley @ 55mm of rake
Cannondale @ 53mm of rake
Co-Motion & Trek T2000 w/carbon fork @ 50mm of rake
Burley Race w/Alpha Q CX carbon fork @ 48mm of rake
Co-Motion & Calfee tandems with Wound-Up forks @ 45mm of rake
Co-Motion & Calfee tandems with Alpha Q X2 forks @ 44mm of rake
If you talk to people who have ridden different examples of these tandems, while the difference in "the numbers" is small, the "feeling" and "handling" of the tandems is quite different. We changed the custom steel fork on our Erickson out for an Alpha Q X2 with 48mm of rake (now discontinued) and it changed the way that tandem "feels" and "handles". Our second Erickson tandem was built around the shorter Alpha Q X2 fork with 48mm of rake and it "felt" and "handled" differently than the other Erickson tandem that has the retrofit Alpha Q fork. Our new tandem is being built around an Alpha Q X2 fork with 44mm of rake: I have no idea how it will "feel" or "handle" compared to our other two tandems. However, none of these tandems "feel" or "handle" the way a Cannondale road tandem does: they are very different.
Bottom Line: If you change out your Cannondale's steel fork with a nominal 53mm of rake for a fork with less rake it will change the way your tandem "feels" and "handles" (Period). If you buy an Alpha Q X2 fork, the front end of your tandem and bottom bracket will be about an 1" lower than it is now. (Period). You will need to decide if these are changes you'd be willing to accept.
oldacura
Once again the obsession with weight. While I applaud your personal weight loss & the adoption of a healthy lifestyle, what is one willing to spend to reduce bike weight a little bit? For a team + bike weight of 370#, 5# is only a 1.3% reduction. On the flats, it won't make any difference. If you presently climb a hill at 10 mph, maybe you'll be able to increase that to 10.13 mph. Is that significant?
We've been passed by teams on heavier bikes & have passed other teams on lighter bikes. The weight of the bike rarely makes any difference.
WheresWaldo
I called and spoke directly to Nimble, they have no problems with using their HorseFly rim with a total 370 pound team. That was provided that the disks are removed and we go to a rim brake. He was very serious about that request. He also felt that a better solution was the Clydesdale Crosswind (tri-spoke) rear and a standard HorseFly front, again provided it was not a disk wheel.
I have no issues with removing the disks.
Ok, I also understand that if I change out the fork I will have to go to a different offset, yes I understand that that will impact steering geometry. TG you mentioned "feel" and "handling" many times in your response but not once have you mentioned if the change caused an improvement or not. I know there is a change, and if I have to use a fork with less offset it will impact the trail by lengthening it, which will result in slower steering. I want to know, when you did that was it good or bad, I already know its different.
OA, look weight is weight is weight, five pounds whether off me or the stoker or the bike is still 5 pounds less to carry. Sometimes is is not about speed, so what if I can climb .13 mph faster, maybe what I really want is to climb at the same 10 mph, but be just a little less fatigued at the top.
I have passed lighter guys on lighter bikes also, and have been passed by heavier guys on heavier bikes, there is more to riding than worrying about who passes whom. But thank you anyway on the comment about my weight loss, it has been quite a journey.
TandemGeek
TG you mentioned "feel" and "handling" many times in your response but not once have you mentioned if the change caused an improvement or not. I know there is a change, and if I have to use a fork with less offset it will impact the trail by lengthening it, which will result in slower steering. I want to know, when you did that was it good or bad, I already know its different.
That's because Good or Bad is highly subjective. I happen to prefer long steering trail on tandems, but then again my wife and me are relatively compact people: 5'8" @ 160 & 5'2" @ 110. Going from our Santana with short trail to our first Erickson with long trail was a dramatic shift, but at the end of the day the Erickson tandems have always been preferrable.
Which DO YOU prefer? Here's how I have characterized them in the past.
Shorter fork trail on a tandem (e.g., Santana) favors low speed maneuverability by providing lighter steering effort and faster steering responsiveness to handlebar inputs. Many teams will describe this as being "more stable" because, at least at slow speeds, it "feels" that way. Tandems with shorter fork trail take less effort and attention to steer in a straight line at slower speed and are resistant to inadvertent movements by the stoker, aka (stoker induced steering). However, tandems with shorter trail also tend to understeer in aggressive or high speed cornering maneuvers which is not always desirable.
Longer fork trail on a tandem (e.g., Co-Motion with Wound-Up Fork) favors high speed cruising and aggressive cornering. This is because of their inherently greater straight line stability and smooth responsiveness to leaning inputs and countersteering. Many teams will describe tandems that handle well at speed as being "more stable" because, at least at higher speeds and for aggressive cornering, it "feels" that way. However, at slower speeds, steering tends to be heavier and less responsive which is often described as being twitchy. Moreover, for teams with stokers that are exceptionally tall, or who tend to move around along or "rock" when they ride, a tandem with long fork trail can make steering control a laborious task that can also be undesirable.
TandemGeek
I called and spoke directly to Nimble, they have no problems with using their HorseFly rim with a total 370 pound team. That was provided that the disks are removed and we go to a rim brake. He was very serious about that request.
That sounds backwards.... I would think they'd want you to use a disc brake instead of a rim brake given the amount of heat that a tandem with rim brakes can put into the wheels. In fact, Rolf offers tandem-rated carbon wheelset that can ONLY support a dual-disc configuration. Rolf, Co-Motion and Advanced Composites collectively developed this carbon wheelset and a disc-compatible Wound-Up carbon fork for tandems. I'm not sure if it has been a hot seller or not.
WheresWaldo
Thank you for the explanation. I have never been particularly fond of or averse to the handling of the tandem. I just never gave it much thought. It is very different than the single bikes we ride with trail numbers all in the 5.7-6.0cm range. I think I would welcome a change lengthening trail. We do absolutely no loaded touring of any kind, and our rides are almost always with singles, as their just aren't that many tandem riders in my part of town SE of Charlotte. It sounds like it would be an actual improvement in high speed performance beyond the weight savings.
My Stoker is small at only 5'2" and is a much smoother pedaler than I am, so I have no issues with rocking. Although sometimes on social rides she has the tendency to forget she is on the back of a tandem and will turn almost completely around to talk to the other riders.
TandemGeek
Once again the obsession with weight.
Oh, come on... Everyone knows that shaving grams from a bike is analogous to taking Viagra.
A lighter, stiffer bike just "feels" better and makes each ride more enjoyable while often times inspiring us to ride just a little longer and harder than we would had we not shaved those grams.
WheresWaldo
That sounds backwards.... I would think they'd want you to use a disc brake instead of a rim brake given the amount of heat that a tandem with rim brakes can put into the wheels. In fact, Rolf offers tandem-rated carbon wheelset that can ONLY support a dual-disc configuration. Rolf, Co-Motion and Advanced Composites collectively developed this carbon wheelset and a disc-compatible Wound-Up carbon fork for tandems. I'm not sure if it has been a hot seller or not.
Here is what he told me, The torque loads on the wheels in a disk brake are much greater than on a rim brake wheel, by an order of magnitude, no other explanation or supporting data. He also dismissed the heat issue with the proviso that it would apply if we were in the habit of riding down mountain grades. he did say in that case that a drum(drag) brake would be acceptable as a secondary means of controlling speed.
I know I have read accounts here and elsewhere of heat induced tire blowouts, they were all clinchers as I recall. Have you had or seen any of these reports on tubulars. There are a plethora of new tubulars in wider widths with the rise in popularity of cyclocross. It could be a viable option for a tandem team. On my single bike I ride tubulars 100% of the time with no reservations, nor have I lacked any confidence in their ability to stay on the rim through the toughest riding situations
RickinFl
In my long tandem career, I don't recall ever knowing of anyone that used tubulars on their big bike. Heard of them being used in velodrome, but not on the road. Might be an interesting experiment if you could find tubular rims that could stand up to tandem (ab)use. Not sure that the tires wouldn't detach and roll off under hard cornering given the weight of a tandem. If you try it, just don't use your face as a brakepad :)
Nice looking Cannondale by the way. How long have you been riding it? Is your daughter the numero uno stoker?
Rick
zzzwillzzz
you shouldn't have a problem rolling a properly glued tubular even on a tandem, but if it got hot from a descent and the glue softened up, i think it would be more likely to roll off than a clincher would be to blow off from too much pressure due to heat from braking.
joe@vwvortex
IMO - everything is a trade off. If you don't decend long downhills at high rates of speed - drop the discs for cantilever brakes. Pauls canti's are much lighter than any other alternatives. If you aren't concerned with flats - run super lightweight tires and tubes. As for wheels - DaVinci wheels are about the lightest handbuilt wheels i've seen at1,958 for the set and they run WI hubs. Their cranks are also some of the lightest tandem cranks out there as well. Next lightest i've found are the old FSA CF with ti bb's. Of course your talking gram counting here. Switching to Egg beater pedals with ti spindles will also save alot of weight as well. Bars, posts and small items aren't going to get you much for your $$$.
The next thing is to go with a much lighter frame - such as a Calfee CF or CoMo Macchiato.
You can discuss grams or you can discuss pounds. You can discuss hundreds of dollars or thousands of dollars. It all depends on what you want. I hate changing flats - so I use heavier tires and tubes. I like having all the brake I can have when doing long fast downhills at over 60mph so I have a rear disc (and want a front regardless of the added weight). I'm willing to have extra weight for those things.
Panito123
Just my observations regarding effects on handling of the C’dale tandem with different fork geometries that may be relevant to this trend. I purchased the carbon fork offered at Chuchsbikes.com and installed it on my C’dale. The ride was significantly different than with the stock fork. To me the bike felt twitchy at slow speeds and was more sensitive to my stoker’s movements. However, at high speed and on turns, the bike felt very stable. This is definitely the result of the fork being about 20mm shorter than the stock fork and having less rake (43 mm). The change in handling is not bad is just something one needs to get used to. We used this fork for a quite a while without any problems. I liked the handling better than with the stock fork as it definitely felt more like my single bike.
Lately I came across a good deal on a Reynolds Carbon Cyclocross fork. I did some research and found that it was approved for tandem use and it was about ½ lb lighter than the one I was using. After installing this fork (395mm length and 45mm rake) the handling changed slightly. The bike is now a little less sensitive to the stoker’s movements. It still handles great. However, under hard braking, I see a bit of deflection on the fork but it does not seem to affect handling.
My C’dale is now right at 36 pounds including pedals, bottle cages, etc. I do not think that I could drop the weight anymore without spending big money or using parts that may not be robust. How heavy are most tandem bikes? I do not know but at 36 lbs I guess mine is about average for a decent tandem. I will post a picture of my tandem so that you guys can advice me as to how to make it better.
Also, does any one else have used the Reynolds cross fork? I am interested on your opinions.
Great forum, GREAT people and sound advice! Thanks guys.
WheresWaldo
In my long tandem career, I don't recall ever knowing of anyone that used tubulars on their big bike. Heard of them being used in velodrome, but not on the road. Might be an interesting experiment if you could find tubular rims that could stand up to tandem (ab)use. Not sure that the tires wouldn't detach and roll off under hard cornering given the weight of a tandem. If you try it, just don't use your face as a brakepad :)
Nice looking Cannondale by the way. How long have you been riding it? Is your daughter the numero uno stoker?
Rick
Sounds like a challenge. I might just try it. It would seem to me that I could dump the disks, go with something like Paul's or the new Kore Cantis and save a bunch of weight.
http://www.paulcomp.com/neoretro.jpghttp://www.kore-usa.com/image/products_image/sport_cantilver_brake.jpg
Rims would most likely have to be Velocity Pro Elites. The Pro Elites are basically a tubular version of the Deep-V in a 36H configuration.
http://www.velocityusa.com/img/r_road_proelite_logos.gif
Tires could be something like these Tufos that come in a 28 and 30mm width:
http://www.biketiresdirect.com/Images400x267/TUD28-1.jpg
Or any of a number of 25mm tubulars from various manufacturers.
Rick, I used to ride and race 20 years ago, then gave up cycling entirely shortly after having my daughter. She got me back into cycling in March 2006. We have had the Tandem since just before Christmas 2005. That was before my GBP surgery, so we just sat and stared at it until I was able to start riding some 4 months later. My daughter is my only stoker. My wife refuses to get on the tandem. I could not even get her to go around the block with me. So my daughter and I ride together. I have ridden with a few others but that was for short sprints nothing more than a mile or two.
WheresWaldo
you shouldn't have a problem rolling a properly glued tubular even on a tandem, but if it got hot from a descent and the glue softened up, i think it would be more likely to roll off than a clincher would be to blow off from too much pressure due to heat from braking.
Here is the thing about tubular glue, this is anecdotal mind you, it is basically contact cement and has a rather high breakdown temperature. I have tried removing the glue from aluminum rims with a heat gun and it basically had no effect. Now chemically, it is easy to remove, nearly any solvent will soften the glue enough to remove it. I am just not sure it would be affected by the heat generated by braking as much as a clincher is. Besides most tubulars are rated for 10-12 bars pressure, much more than the 8 bars I typically run, so no real fears of blowouts either.
WheresWaldo
Just my observations regarding effects on handling of the C’dale tandem with different fork geometries that may be relevant to this trend. I purchased the carbon fork offered at Chuchsbikes.com and installed it on my C’dale. The ride was significantly different than with the stock fork. To me the bike felt twitchy at slow speeds and was more sensitive to my stoker’s movements. However, at high speed and on turns, the bike felt very stable. This is definitely the result of the fork being about 20mm shorter than the stock fork and having less rake (43 mm). The change in handling is not bad is just something one needs to get used to. We used this fork for a quite a while without any problems. I liked the handling better than with the stock fork as it definitely felt more like my single bike.
Lately I came across a good deal on a Reynolds Carbon Cyclocross fork. I did some research and found that it was approved for tandem use and it was about ½ lb lighter than the one I was using. After installing this fork (395mm length and 45mm rake) the handling changed slightly. The bike is now a little less sensitive to the stoker’s movements. It still handles great. However, under hard braking, I see a bit of deflection on the fork but it does not seem to affect handling.
My C’dale is now right at 36 pounds including pedals, bottle cages, etc. I do not think that I could drop the weight anymore without spending big money or using parts that may not be robust. How heavy are most tandem bikes? I do not know but at 36 lbs I guess mine is about average for a decent tandem. I will post a picture of my tandem so that you guys can advice me as to how to make it better.
Also, does any one else have used the Reynolds cross fork? I am interested on your opinions.
Great forum, GREAT people and sound advice! Thanks guys.
Great info, I am going to look at the Alpha Q cross, it is still available in a 47mm offset and I will look for the Reynolds to compare, but I think I have a new winter project. I was going to work on a winter bike first, the frame is at the powder-coaters right now and should be done by the end of the week. I may just box that up and build another set of wheels, this time for the tandem.
Panito123
As mentioned here is picture of my tandem. According to my scale it is right at 36 lbs as built. Does any one have a lighter C'dale? What did you do to make it lighter/better?
zzzwillzzz
Here is the thing about tubular glue, this is anecdotal mind you, it is basically contact cement and has a rather high breakdown temperature. yeah, that's why after warming up on my clinchers for a race, i pulled out my sewups out of the hot car and they were definitely not ridable as the glue was very soft and the tire would have rolled for sure on the first corner
pros also occassionally roll tubulars on steep descents in races like the tour de france from overheating the rims