Steve.D

I love my bike but the wheels keep giving me grief. I practice regular bike maintenance. But In the couple years which I have owned this bike, I have worn out bearing races, replaced broken spokes, and even had a hub flange break.

I have come to fear that I might experience a catastrophic wheel failure while on a long tour away from help. Meanwhile, I have slowly realized that there isn't anything wrong with the wheels. Rather the wheels are not designed to support my 240lb body. On top of all this, replacement parts are hard to find and I usually have to settle for used.

So rather than loose some weight, I have decided to replace the wheels with something more robust. And while doing this, I might as well update the gearing at the same time.

But when I do this, I would like to choose components that blend in with the look of vintage bike as much as possible. (However, I'm sure there's going to be some compromise.)

The current relevant components are:

Hubs:Maillard 100/126mm OL
Rims: 27" Matrix Anodict 22mm wide w/ 1-1/4" wide tires
Spokes: 14 gage, 3x pattern, 36 spokes per wheel
Freewheel: Helicomatic 6sp 14-16-20-23-28-32
Crank: Shimano FC-6206 48/44/28
Rear Der:Shimano Deore MT60
Brakes: Shimano BR-MC70 cantilever

Here's a link to Mike Sherman's Gear Calculator which will display the current gearing:
<CURRENT RATIOS> (Hit the Okay button that appears on the web page)

So, I am wondering if anybody can offer some advice or comments on what to chose for the upgrade. Here's what I'm thinking of using:

New Hubs: Shimano 105 100/130mm OL
New Rims: Velocity Dyad 700cc
New Cassette: Shimano HG61 9sp 12-14-16-18-21-24-28-32-36
New Rear Der: Shimano RD-M772 XT Rear Deraillier
Crank: Keep existing
Brakes: Keep existing

Here's a link that shows the new gear ratios: <PROPOSED RATIOS>

I choose the 105 hubs in order to use a cassette. I'm hoping to spread the rear stays without problems. And I do believe the canti brakes will adjust enough to accommodate the new wheels size, but I haven't confirmed that yet. I really like the gear ratios of this setup which is accomplished with the new cassette and rear derailleur.

Does anybody see any reason why these new components may not work?. Any help no matter how slight would be greatly appreciated.

Sorry for the long post. But I just wanted to have all the information out there.

Thanks!

thenomad

What shifters do you have? I assume barends? If they are friction you'll be fine with them. New RD, New Chain, New Cassette and wheels sounds good to me.
If they are indexed you'll need new 9sp indexed ones or get barcons that take friction downtube shifters. I don't think you'd have trouble with the 6 speed spaced crank but you might want to get it in gear carefully so the narrower chain doesn't jump in between the chainrings. Doubt that'd happen but it only takes once.
what's the spoke count on the Rear wheels? You may want to spring for 36 hole or 40 and just build a bomb proof rear wheel for your weight and the touring load. Do it right, do it once.

PICS!

Steve.D

Good points Nomad.

The shifters are the original Suntour Barcons. And I'm fine with keeping them and staying friction rather than indexed.

A narrower 9 speed chain on the front rings may be an issue. I'll have to check into that. Thanks!

I don't have any pictures. But the bike looks just like this one, except mine has barcons: <SIMILAR BIKE>

Trucker Dan

Here is some inspiration. I updated mine for cyclocross.

Why do you need such a wide range cassette if you are going to leave the triple on. I would go for a 12-25 10 speed so you will have smaller gaps between the gears. I am running a 34-45 crank and a 12-27 on mine. I have no problems with the crazy steep offroad cyclocross hills. Another thing to watch for is your bb will sit a little lower with 700c wheels. You will have to be more aware when taking turns hard to prevent pedal strikes. If you don't want to spend a lot right now I'll sell you my old wheels for super cheap of you want them.

Steve.D

Nice bike and very inspiring! Those rims are perfect. What size and brand are they?

I am always looking for vintage parts. So if you got some rims or other parts for sale and if they are in good condition, then please send me a private message and we can do business.

Okay, now to reply to your question: The reason I need lower gears is because I use this bike for fully loaded self-contained touring. I am an old guy and would like to have a lower gear in order to pace myself over long steep climbs without blowing out my knees. I some times fell like I'm pedaling a pickup over the mountains.

Anyhow, the gear setup I am considering has a lot more gears (27) than what I am use too (18). But what I am trying to accomplish is to gain at least one more lower gear and one more higher gear, and do this with smaller increments between the gears than my current setup.

The cassette that I have chosen can do that (plus a little more in the high end) It is the best gear setup I have come up with so far while retaining the existing crank.. I would like to avoid replacing the crank because I really like the current one which is thee original.

If you look at the gear ratio chart for the new gearing (there is a link in my original post), you'll see that the gears are spaced very evenly apart. I probably could get by with one big ring and the granny. But it helps to have the extra big ring half-step up or down when faced with strong head winds and carrying extra heavy loads.

The pedal strike issue is something I hadn't thought of. Thanks for bringing that up too.

Six jours

You might find friction shifting with the above components kind of frustrating. I do. If you can find a way to try 9 speed friction with a long cage derailleur before spending the money, it might be a good idea. Otherwise, I'd consider indexed bar-ends as well.

I'd also consider a stronger rim at your weight. The Mavic A719 comes to mind, and is still fairly traditional in appearance.

Finally, in my experience the cantilever bosses aren't always in the right place for the conversion, so you may want to borrow a wheel to check.

thenomad

Oh crap, totally forgot that tidbit about the cantilever bosses. You had 27s and are doing the conversion to 700 so the bosses will be too high by a few mm but oh so critical ones at that.

It can be a real pain in the butt to get them to work just right. Your current brakes may or may not have enough adjustability to work correctly. You might need to get 90s MTB cantis as some certain brands seem to work well. Another option is some spendy adjustable ones. I did the conversion with adjustable onzas but never really liked the feel of the brake as you really need to get the straddle cable and toe in etc just right.

It may be worth it to buy a good high spoke count 27" rims with the new hubs. 27 touring tires are available and the gearing isn't going to matter much.
Any way to borrow a wheelset for brake adjusting purposes before you spend the big $?

southpawboston

Steve, you mentioned you have BR-MC70 cantis on this bike. Those have been used successfully on lots of 27" to 700C conversions because of the built-in vertical adjustability. Try loosening up the adjuster nut on one of your cantis and see if there's enough vertical range to allow the pad to seat 4mm lower than it does now-- that should give you an idea of whether it will work on a 700C rim.

As for the BB drop with the slightly smaller rims: 4mm of drop may or may not be a big deal, depending on the BB's original height. You might want to consider getting 35mm tires instead of 32mm tires, which is what you have now-- the extra 3mm will add comfort, and will effectively negate any height drop introduced by the rim swap. I'm pretty sure the Trek 720 can accommodate tires at least that wide.

Standalone 

TheNomad, were those the Onza HO's? I have a Trek 620 frame and am reading up on making the 700c conversion.

Trucker Dan

My bike has ultegra hubs with 32 spoke open pro cd rims. I was able to adjust the original xt cantis to fit the 700c wheels. They are at the limit of their adjustment and I cant get the pads to hit the rim totally flat, but once you get in some miles the pads will wear into the rim just fine. I had to slide the rear wheel all the way back in the dropouts in order to help with brake adjustment. The trek frame builder eyeballed the placement of the canti bosses when brazing them on and the left one is about 3mm lower than the right. It make is hard to adjust it. Since it appears trek didn't use frame jigs for the canti bosses, if yours are on the high side you may have problems.

balindamood

My 2-cents:

1). Suntour friction bar-cons with anything over 7-speed is a royal PIA. The needed for precision to hit those gears is simply too much. Either spend the extra $100 on SIS bar-end shifters or use a 7-speed cassette. This will also fix your chain-ring problem with the narrower 9-speed chain, but may also force you to drop the high-dollar XT derailleur (potential pully problems...designed for 9-speed chains). The Shimano MT60 derailleur (assuming it is the Super plate model) was reasonably reliable, but when they go, they go catastrophicly. If you are staying with frinction shifting, I suggets spending $20+/- on any old Suntour VGT or Cyclone derailleur. They will do just fine and evidently last forever. Staying with 6/7 speed also eliminates the likely neeet to re-set the rear triangle of the frame to handle 130mm hubs.

2). Contrary to popular belief, butted (or swaged) spokes are stronger than straight guage assuming that the wheel is properly built. I would stay with no less than 36-holes, but would not be concerned if you only find 14/15/14 spokes versus straight guaged 14's. If it is possible to build up a 40-spoke rear wheel, I would take it. It is very hard to find a free-hub style 40-hole hub that is not designed for tandems. You can probably re-space a tandem free-hub to fit your 720 (never tried it, but you will likely need a shorter axle). They did make 40-hole Deore XT freehubs for 1 year (1990 I think) which can be switched to 9-speed if you go that direction, but again, VERY hard to find. It will be easier to find a traditional free-wheel 40H hub...locking you to 6/7 speeds. Finding 40H rims is also a bit more difficult, but they are designed for tandems, so they will be very strong.

3). You should not have a problem sitching from 27-inch wheels to 700C (4mm difference at the bead-seat).

Best of luck. I have been riding my fully loaded touring 1985 or 6 Lotus for a couple of years now. Trying to keep it "period" has not been an issue. Though I never had a problem, it came with all cartridge bearing mechanicals (BB and hubs) which I have replaced with cup and cone versions because I can fix those anywhere.

Six jours

One "hallmark" of classy frames is that the brake pads fit down into the bottom of the cantilever slots. I've seen several that just didn't work with the conversion - though most were fixable by filing the slots. So it is worth double checking.

qualla

The cantilever boss question can probably only be resolved by actually trying a comparable wheel (rim width also matters) on that fork (boss placement was not always standard). Experiences seem to range from "can't do it at all" to my experience with a Univega Specialissima: mount the new wheels ride off (OK, I tweaked the angle of the pads slightly on the old Dia-Compe copies of the Mafac Touring canti).

The Dyads should be strong enough - you can even get them in 40 or 48 hole drilling if you want extra insurance. It may also be worth the expense to have them built by an expert for even greater reliability.

My experience with friction shifting is better than balindamood's. It has been easy for me up to eight cogs (Suntour barcons and Huret downtube). But on the whole I think that balindamood's suggestion for using a 7-speed and an older friction derailleur are good. The chainrings may be a bit of an issue, they may not be happy with a 9-speed chain. Too, speaking from my own experience, I think that the improvement in shifting over the last 30 years is due more to improvements in cogs, chains and chainrings moreso than to the undoubted real improvements in the derailleurs. I'd probably pass on the new derailleur and spend the money on good cogs and maybe a new chainring or three.

Good luck.

Steve.D

I finally got around to doing the upgrade couple weekend ago. Below is a list of the components I wound up using and a link to some pics. Thanks to everyone for the help!

Mavic A719 rims, black w/ machined sidewalls
DT Competition Spokes, double butted 2.0/1.8/2.0mm, 36 per wheel
Velo Orange Grand Cru Touring hubs, 130mm rear, 100mm front
Continental Gatorskins tires 700c x 32
Shimano Deore XT RD-M772 SGS rear derailleur
Shimano HG61 9 speed cassette 12-36t
Shimano Dura-Ace bar end shifters

Kept original Shimano cantilever brakes, they had enough adjustment to move down to 700c rim.
Kept original Shimano crank. I like the looks of it and the half-step gearing.
Kept non-original Shimano Deer Head Front derailleur

Drives like a dream! Shifts smooth as silk. Thanks for all the helpful suggestions. You gave me the confidence and great advice to make the upgrade happen!

I posted some pics on my Picasa site: <click here>

b dub 

My jaw dropped when the pictures came up. Wow, that is one awesome machine. I usually like a more original look, but the changes you made make total sense. I even like the derailleur. I do have to say that I love it that you kept the original crank and canti's. Great job! Now ride the heck out of it...

robatsu

You better keep the brakes, those ones are some of the best for converting Trek 620/720 to 700c. Trying this w/modern cantis is a real hit/miss proposition, you end up filing brake pads and crazy stuff like that.

I friction shift 9 speed fine. But that doesn't mean it is ok for everyone. The next thing to do is get you some Dura Ace SL-7700 down tube shifters, way cheaper than brifters. You can run them in either 9 speed index or friction mode, so you can then make a choice. Just make sure that the derailleur you chose is ok w/Shimano 9 speed cable movement, but the one you've chosen probably is.

That hg 61 is pretty interesting but they are pretty heavy, like a lb or so. Me, I'd opt for a 12/27 w/a triple and go for a 24 tooth granny. That gives 24 gear inches, but maybe it isn't enough for heavily loaded rides up steep hills, so you may be on to something w/that.

The Golden Boy 

That is a sweet looking bike!

I love what you did with it and how it still looks "classic."

Ciufalon

That is beautiful. You did a terrific job of putting that bike together in a very attractive and practical way. Enjoy the riding!

Steve.D

Thanks for nice feedback! I will be riding the heck out of the bike during a tour of the Oregon Coast soon.

Yes, the HG61 cassette is heavy which was an issue I had considered. But the the old Maillard 6 speed freewheel it replace was even heavier. Since I wanted to keep the original crank, I choose to go with a cassette with the largest rear cog possible, hence the HG61. I could put a smaller granny ring up front. The current granny ring is the original 28t and could be changed out to a 26t without any problems. Any smaller and the chain rubs the bottom of the front derailleur cage.

The 700 c rims provide a bit more clearance between the tire and fender. This was an issue before, especially in the Fall when leaves would get picked up and clog up under the fenders. The new rims are a few millimeters wider too, making the profile of the 32mm wide tire spread out a bit more than they did on the original narrower 27" rim. The end result is the bike is more comfortable due to the rims wheels adsorbing more of the impact. The brake perform much better too because of the machined sidewalls.

The shifting is way superior due to Shimano's Hyperglide cassette with those chain ramps machined into the cassette. The huge long cage of the XT rear der keeps the chain tensioned perfectly. I'm using the end bar shifters in friction mode, which is okay with me. I may have to trim a little if I over/under shift but usually the chain just snaps into position. The shifters can be switched into STI mode, but that doesn't work with the cassette and rear der. (Perhaps I just don't know how to setup it up correctly. I admit to being STI illiterate.)

shelbyfv

Great looking bike, like those VO hubs. If your bar end shifters are 9 speed they should work indexed.

Steve.D

The bar end shifters are designed for 9 and 10 speeds. But Shimano put several warnings in the installation instructions that they were compatible only with a certain (racing type) cassette and derailleur. I've read on this forum that some people have gotten these shifters to work on mountain bike cassettes and derailleurs though. I may have to have a pro mechanic adjust the cable tension or something. Thanks for the comments.