Road Cycling - Big cogs isnted of triples?

I see more than a few bikes with a triple, the inside ring at 30 t and the largest cog at 25 teeth (some maybe at as few as 23 teeth). Why not go with a double, 52/39, and have the largest cog at 34, giving a lower ratio than the triple?

well... the main reason, i guess, is that few road rear derailleurs can handle more than 27t. you can always swap out the rear for a long-cage mtb derailleur, of course, giving you a maximum capacity up to 34t. the trade-off is that it won't shift as smoothly as a road rd with a narrower range... which brings up another thing... when your cassette ranges from 12 to 34, you lose a whole lot of those intermediate gears, since the difference between each cog is pretty wide. some people, i guess, prefer to have a tighter range of rear cogs...

having said that, i really do think that gears lower than, say, 39x27 are a bit of overkill if you ride a road bike [not a tourer]. are in reasonably good shape and don't happen to live on the side of a mountain. i think a lot of people buy triples because they are afraid, and end up rarely, if ever using the granny gear.

just my little rant.

Originally posted by velocipedio
i think a lot of people buy triples because they are afraid, and end up rarely, if ever using the granny gear.

Or, that's what the bike came with and they plan on switching the rear and front derailleurs and crank as soon as possible. ;) When I bought my bike, I didn't have a choice, it came with the triple crank in the front and the long cage derailleur in the rear. I've never ridden a 27 speed bike and I'm not thrilled with the look of the long cage derailleur in the rear (stupid reason, I know). I'll probalby swap them for double units if Nashbar or someone has Ultegra parts on sale. I know I'm not going to use 27 gears and I don't like having stuff on my bike I'm not going to use.

- Matt

I mostly depends on where you live, IMHO. When I lived in the DC area I never thought to use a triple. The places where the hill was long enough and the grade steep enough were few and far between. So a triple just wasn't worth it.

When I moved to California I found that the hills were longer and, I think because it doesn't snow, the grades were steeper (or maybe I'm just getting older. :( ). After a couple of years avoiding certain climbs and killing my knees, I gave in and switched to a triple and have never looked back.

I do not believe that the triple has slowed me down. To the contrary, I think that I can climb more efficiently because I don't have to stand but can remain seated on longer climbs. If I need to I can always upshift and stand when my muscles and butt need a break.

The other nice feature of the triple is that I can keep the rear cluster range closer together which helps me to maintain my cadence when cruising on rolling terrain.

I'm sure that I'll be appreciating the triple when I do the 9 mile climb up Tunitas Creek Rd. this weekend at the 70 mile mark.

SteveE

If you need the gears on a road bike then the triple is better. The wide range gearing on a mountain bike cassette will radically change your pedal cadence and screw up your rythm. Trying to maintain a pace while making cadence changes that extreme would be loads of fun.

Originally posted by velocipedio
the trade-off is that it won't shift as smoothly as a road rd with a narrower range...

you can't forget the other trade off.... the looks of disdain from horrified bike snobs :D

it's worth bearing in mind that even roberto heras rode a triple -- and won the stage -- on the angliru in the vuelta last year...

Originally posted by deliriou5
you can't forget the other trade off.... the looks of disdain from horrified bike snobs :D
Right you are. Of course, those are the ones that won't ride with you in the hills either!:rolleyes:

Given the 9 and 10 speed cassettes that are now the norm, a triple is hardly necessary except for loaded touring. It's more about sales and hype than anything.

Regarding using bigger cogs: many randonnuers set their bikes up using stuff like a 38/48 up front with a 12-27 in the back. Those wanting really low gears fit a 11-34 on the back with a mtn bike rear derailler. It will work just fine with your road front der and shifters.

Dave

With typical modern setups, it allows for closer gears. However, if one uses a gear calculator such as http://www.sheldonbrown.com/gears , one realise that many cogs are duplicates, so a well-designed double could give as many useful gears. If you look 20-30 years back, many commercial freewheels had a wider gap at the bottom and closer ratios at the top.

I do loaded touring and also cycling with kids in tow, besides, I'm not a strong cyclist. So I made my custom cassette with these ratios:
12-14-15-16-17-19-21-25-32. The gaps at the lower end are huge, but these are gears I rarely use except on steep hills. Nevertheless I'm happy to have them.

BTW, 20 years ago, Suntour had a few 5-speed and 6-speed cassettes with a 38-tooth large cog.

Originally posted by hayneda
Given the 9 and 10 speed cassettes that are now the norm, a triple is hardly necessary except for loaded touring. It's more about sales and hype than anything.

I disagree.

Technical Advantage: While 9 and 10 speed transmissions give you a wider gear range, they come at a cost -- which as others have noted is the loss of the close-ratio intermediate gears. A 12 x 27t is about the last 9 speed cassette combination you can use before you start getting big gaps in gear-inch changes. While many of you might find that a 38 x 27t is more than what you need to take on 10 mile long, 10% climbs others would prefer to have their cake and eat it too, i.e., maintain the semi-close ratio 12 x 25 or 27t cassette but get that shorter gear by "bailing-out" to a 28t granny ring.

Technical Disadvantage: Added weight of the 3rd chain ring and longer rear derailleur cage.

Target Markets: IMHO, it's not about hype as much as it is about offering a feature that more road bike consumers are now looking for. More specifically, I believe the more prominent appearance of triple chain rings on road bikes (vs MTBs, Touring bikes and tandems which have been using them for decades) has more to do with two market trends:

1. Similar to my theory on compact frames, one of the larger new markets for road bikes is the mountain bike rider who's finally realized they don't actually ride their mountain bike off-road. So, they have decided it's time to buy a road bike and they sure did like having that granny gear for the hills. So, like compact frames, adding a triple chain ring to road bikes provides these buyers with a more familiar package.

2. In addition to your cross-over MTB buyers, the major consumer demographic for new road bikes are the existing owner / buyers who are getting older (present company included). Baby boomers in particular are a large part of the road bike market and there are three scenarios that answer the question of "why a triple" is now desireable for them:
a. The hills feel like they are getting steeper.
b. They prefer to enjoy the journey vs being the first to arrive at the end and not kill themselves on the climbs .
c. Mid-life former MTB riders and racers find they have been consumed with work & families but decide to rejoin other life-shackled former racer-mates whose mid-sections somehow seem closer to the top tube than they used to be.

I have a triple on my Trek. And I really don't give a .......... about what people think. If and when I need extra gears I have them. If I don't need them what penalty do I pay, 2 or 3 ounces of extra weight? I don't race so weight and allegedly faster shifting is not an issue. If nothing else I look at the granny as being a "frame saver" of sorts.

Originally posted by mgagnonlv
So I made my custom cassette with these ratios:
12-14-15-16-17-19-21-25-32.

mgagnonlv: I have a couple of questions for you:

1 - where did you get the custom cassette? Can any LBS make one like that?

2 - Do you use a long or short rear derailleur cage with this setup?

Thanks!

Zack

Zack, I beleive SRAM has a custom cassette deal in some of the bike catalogs we have gotten in the past. Just can't remember which one.

If you look on Sheldon Brown's web site he has an article on building your own cassette.

I guess I'm just a wussy, but I use the granny gear a lot, especially when riding into 40+mph winds. On the other hand, I don't use the large ring very often.

As Rainman can attest following his excellent San Diego cycling adventure, the close-ratio half-step-plus-grannie gearing I put on my Peugeot works very nicely. The Shimano 600 racing-style front derailleur has no trouble handling the 48-45-34 triple, thanks to the small drop between the two outer rings. Likewise, my short-cage SunTour Cyclone rear derailleur and 13-15-17-19-21-23 freewheel shift great and look "correct," while covering a traditional general-purpose 40-to-100-inch gear range in fine-grained increments.

If I had a modern 9-speed cassette, I would consider a 2x9 18-speed combination instead of my 3x6, with something like 48-38 or 46-38 / 13-14-15-16-17-19-21-23-25.

The secret is to avoid wasting valuable gear combinations on ratios above 100 gear-inches.

My opinion used to be pretty much what Velocipedio said in his first response, but I've since backed off. It works for me, but based on weight, condition, terrain, preferences, etc., etc., a double just ain't for everybody. If you're worried about it, go for the triple... it's better to have the granny when you need it. When you become an iron man, er, person, upgrade to the double, instead of hatin' life, riding the double wishing you had a triple.

But, I second what Livngood said... if you get a triple, go for the tighter range cassette (heck, they're not all that expensive and easy to swap...) cut your chain to handle a 12-27, it'll work fine down to a 12-23 (maybe lower... haven't tried yet). Or go for a 12-25, 11-21 range. When you're going fast or climbing, there's just something so sweet about looking for just the right gear, and finding you have it!

Originally posted by John E
If I had a modern 9-speed cassette, I would consider a 2x9 18-speed combination instead of my 3x6, with something like 48-38 or 46-38 / 13-14-15-16-17-19-21-23-25.
interesting... that's pretty standard cyclo-cross gearing. my 'cross rig is set up with 48/39 in front and 14-15-16-18-20-22-24-26 in back. i love the gearing for almost all contingencies, and any hill that i can't get up in 39x26 i'd probably run faster, anyway...

my roadie has a standard 53-39 / 11-23. i do use the whole range, though i only really use 11x23 on descents. 39x23 is enough for every paved hill i've come across to date.

Originally posted by velocipedio
39x23 is enough for every paved hill i've come across to date.

In 1986 I would have told you there wasn't much I couldn't handle with my 52/42 set of chain rings and my 11-12-13-14-15-17-19t 7spd corn cobb freewheel (you know, back when they threaded on and really looked like a corn cobb)...

By 1992 my knees began to protest even though I'd moved up to 53/39 chain rings and a 12-13-14-15-16-17-19-21t 8 spd cassette...

Now I ride a 11-12-13-14-15-17-19-21-23t 9 spd cassette and keep a 12-13-14-15-17-19-21-23-25t 9 spd cassette in my tool box that goes on when I head for the mountains. Cest' la vie.

Rolling your own cassette is simple. Just disassemble the 4-5 cogs that are usually rivetted or screwed together then put together what you want using cogs, from another cassette or a couple of individual cogs, about $8 each, from someplace like harriscyclery.com. To determine whether the cogs are screwed are rivetted just take a look at the (usually) 3 fasteners holding them together. If both ends of the fasteners are smooth they are rivets. Just take a Dremel tool and grindstone and grind away enough of the peened head to get the rivet out. If there is a tiny hole in one end of the fastener and the other end is small, the hole is actually a tiny allen head screw, 1.5 or 2 mm, I can't remember. Just unscrew the screws. I do not consider myself a strong cyclist so I like to start with a 14-25 cassette, pull the 23, move the 25 over and add a 32 or 34. This gives me nice close ratios for flat riding and a couple of nice low gears for hills. I have a 48/34 up front so the 34 in back gives me a low gear of 27 inches, low enough for all but serious mountains. I only put this low gear on when I know I am headed for the hills. I also replace my DA rear der with an XT or LX to handle the big cog. I seldom replace an entire cassette. When cogs get worn I replace them with leftover cogs from a cassette I have cannibalized or with individual cogs. Why spend $40 and up for a whole cassette when only a couple of cogs may be worn. By the way, shifting is fine with this setup even when I replace a particular cog with one intended to go in a different setup (HG cogs are desgned for a specific setup. A 19 that goes between an 18 and a 21 is slightly different from a 19 designed to go between a 17 and a 21.). If you put a different cog in there may be a split second difference in the shift, but I doubt you could detect it. Besides, we are not (at least I am not) talking about racing. That is a different situation calling for a precision setup.

Some took interest in my custom cassette. I took the idea from Sheldon Brown's site, namely at http://www.sheldonbrown.com/k7.html and http://www.sheldonbrown.com/harris/k7.html.

The Cyclotouriste 13 and 14, the High and Wide and the Classic 9 are all cassettes made from a modified Shimano cassette. For instance, the Cyclotouriste 14 starts as an Ultegra 12-27, with the 12, 13 and 14 replaced by a 14 outer cog and 2 loose cogs, 30 and 34 added to it.

In theory, single sprockets should be sold at your favourite LBS; however, none in my area were selling them and none were even prepared to order them. However, if you look at the table found http://www.sheldonbrown.com/k7.html#9cassettes and at instructions found http://www.sheldonbrown.com/k7.html#custom , you will notice that all "lower end" cassettes, use separate cogs. Avoid selecting a high-end cassette that uses a spider (3 or 4 cogs assembled together), unless you want to use these 3 or 4 as is.

What did I do? I used two cassettes, a 12-25 (HG-70 series) and a 12-32 (LX series), unscrewed the little Allen screws that were holding the 5 or 6 largest cogs together, and I used the bunch of loose cogs to mount my custom cassette.

Well, it was actually slightly more elaborate because I used two new 12-25 cassettes, one new 12-32 as well as one existing 14-32 7-speed cassette to customise three bikes (one started without a cassette).


A few tips

Regarding indexing: Sheldon Brown suggest that ramps are most important for the largest jumps. I tried as much as possible to use a cog that came from the same series as the smaller cog sitting besides it. For instance, for the jumps between 17, 19 and 21, I used cogs from the 12-25 cassette. In practice, I haven't found a difference between jumps that were supposed to match and jumps that weren't.

Regarding mix-and-match. One bike is 9-speed friction, one is 7-speed friction and one is 9-speed indexed. I used the appropriate 9-speed or 7-speed spacers, but I did not always use the "proper" cogs for the number of speeds. Most of the spacing difference comes from the spacers, but 9-speed cogs are slightly thinner than 7-speed cogs. It so happens that the 9-speed indexed bike uses 3 of those 7-speed cogs and that was enough to play havoc with the indexing. A good file solved the problem.

Regarding friction shifting: I prefer friction shifting, especially in Winter. Friction shifting a 9-speed cassette is much easier if you reverse the cogs so the ramps don't contribute to ghost shifting. Cogs are easy to reverse... once one notch is widened.


BTW, my rear derailleur is a Shimano XT (long cage). A medium cage road derailleur is said to easily shift up to 30 and "maybe" up to 32, but it won't take the 40-tooth overall gap that I have.

Regards,

Originally posted by livngood
I disagree.

Target Markets: IMHO, it's not about hype as much as it is about offering a feature that more road bike consumers are now looking for.


My point is that given a 9 speed cassette, the average rider can get all they need with a double. Of course, the real problem is that the commonly available hardware is way over geared. I mean, who uses a 53/12?

It used to be that one could custom build their own freewheel with exactly the cogs they wanted and the same for the chainrings. Many used 110BCD cranksets so they could use a double alpine setup with a 34/48 on the front. This yielded all the low gear anyone should need for all but loaded touring.

I do think that triples are swell and do have them on two of my bikes (a full bore touring bike and a tandem). But one can do well with just a double with thoughful selection of chainrings.

Also, while it's not well known, you can get individual cog parts for shimano (I don't know about campag) and rebuild your cassette to get sorta what you want (you have to work around the sets that are riveted together). For example, I really like a 16t and the 12/27 doesn't have one. Well, as a rando long distance rider, no one uses 12t. So I rebuilt the cassette with a spare 16t and a 13t with end spacer, both of which can be had from ****mo. If I wanted, I could also replace my current crankset with a 110BCD and install 34/48 chainrings. That's getting to be a pretty low gear. I could also swap rear ders for a mtn der and go with a 12/34 or so in the back--a gear which can nearly pull a car out of the ditch.

As far as gear gaps are concerned. That used to bother me, until I started riding fixed gear. Now I actually find little gaps irritating, since my legs are used to a wide range of cadence. I find myself doing a lot of double shifting because of this.

Dave

I see single chainrings making a comeback on roadified MTBs in London. With 9/10 cogs, and a good chainline, you have 9/10 gears. That is about the same as a 2x7 system.
If Shimano or Campy dont make the cogs you want, check out Marchisio.

In my experience I think that gearing has a lot to do with percieved suffering. I think that some people seem to believe that they are suffering less when they can maintain a fast cadence on a climb, perhaps they are suffering less, but they almost always get up the hill slower. In my experience I have become a better climber riding 39x26 and mashing up hills quickly as opposed to riding my three ringer and spinning up hills.

BUT

me and brother were racing the other night and we hit the steep hill on our training ride. I mashed up it while he droped to his granny. I was several lengths ahead of him and was confident that he wouldn't catch me. Near the top their is a lull in the hill and while I was hurting too much to really take adavantage of it, he was able to spin up even faster and make up my lead. At the top we were both hurting but I think he recovered faster since his legs hadn't built up so much latic acid, or he might be in better shape then me?

Originally posted by gattm99
I was hurting too much to really take adavantage of it, he was able to spin up even faster and make up my lead. At the top we were both hurting but I think he recovered faster since his legs hadn't built up so much latic acid
Bingo! Being first up the hill ain't worth a dime if you're so cooked that you can't capitalize on it. And, too, if you can spin fast enough in a lower gear, you get the best of both worlds, speed and recovery (a la Lance vs. Jan).

I think the real problem is that the tallest gears are unrealistic. At 100 rpm a 100 inch gear gets you almost exactly 30 mph. In general that is getting into the range where I start thinking about ways to control of reduce my speed, not enhance it. the real problem I see with most doubles today is that they have too small a small cog and then too small a large cog. I would not be so put out with a 39 chainring if I had something at least 28, and maybe larger. If I remember correctly my schwinn varsity had a 39 or somethng like that for the small ring, and a 28 in back. That was challenging but usually enough, with only 5 cogs in back. Now that we have 8, 9 or even 10 cogs, it would make more sense to have more teeth on the largest cogs. what happened instead is that the smallest cogs got smaller and so did the largest. Then we have to fix the problem by adding a thrid chainring. the ranonneur setup above seems a lot more appealling to me. It is kind of tough to find those large chainrings in between 44 and 52 though. The only one that seems to be made in any kinds of numbers in that range is the 46.

I don't hate triples, but I am really miffed at the nonsensical limits placed on doubles by what appear to be the style police who think we all need the same gears as lance. I might enjoy a bike as light as his, but I damned sure can't push the same gears.

I prefer the tripple with closer spaced rear casett in the rear. I ride a converted mtb on the road, it's a 7spd, and the change from one gear to the next is too large for me on the road.
This is just my preferance.

I have been having this dilema for some time now. I currently have a double on my bike that I swapped in from a triple. It's all Ultegra and I have a 52/38 12-27. This set up provides me with good range of gear inches but I always find myself wanted that lower gear on bigger/longer hills that lie in the Blue Ridge/Piedmont of Virginia.

I loved the gearing of the triple but I could never get it dialed in right. It would always rub the front der. and I couldn't stand the noise. Picky aren't I?

So, in my quest for a lower climbing gear I came across Peter White's website and found he sells Specialized TA Zypher Light cranksets in either a 50-36 or a 48-34. With a 12-27 in the back I could get a low 33.1 gear inch. You can also customize the chain ring sizes for both the big and middle rings. They are 110 bolt diameter as opposed to the 130 bolt diameter used by Shimano and Campy.

I was wondering if anyone was using these cranks and how they like them.

Sean

Ok- suppose I had purchased a 2x9 with a 12-25 in back and a 53/39 Ultegra in front- what is the most economical way to get realistic gears- I'm thinking that going to a Deore LX 44/32/22 crankset with the little ring removed would be a good way to go. This assumes the shimano splines are interchangeable between mountain and road. I think that would cost around $70, and involve changing one part and moving and adjusting the front derailleur (which further assumes it is clamp-on, not braze-on). That would give me 34.6 inches to 99 inches. As a bonus I would lose about 50 grams.

Alternative 2 would be to go to a Deore XT Derailleur, $50, +30 grams, and an XT rear cassette, 11x34, $50, +94 grams. this would give a high of 130 inches and a low of 31 inches. This gets a low gear about 12% lower than option 1, and lots of not very useful higher gears, for about $100 and adding 124 grams.

Homebrew,
I have a Specialities TA crankset (51/38). I love it. It's also beautifel, someone called it "bike jewelry) I put it on last year and with my campy 10 I find I can climb as well as riders with triples, at least the women (and often men) I ride with. However, there are still a few hills I walk but I think I would walk them with a triple. I'll only push my knees so far and since I'm almost 55 I have nothing to prove.
Kathi

Kathi