So I invested in my first ever triathlon bike, and I decided to try out compact cranks. 2 years ago I had swicthed from a 39/53 and 11-23 to a 39/50 and a SRAM 12-26 and I loved it. I couldn’t beat my friends down the hills anymore, but I wasn’t doing road races and I found that I had a lot more gears to choose from, with the bonus of being able to spin most of the hills in my area if I chose to.
When choosing a new bike, I decided to try the new gearing that a compact provided. I figured that I could get an easier climbing gear AND a bigger hammer gear at the same time. So I went with the 34/50 up front with a 10sp 11-23 in the back.
OK, so as soon as I got the bike, it occurred to me that maybe I should have looked into what happens to the middle of your gearing range when you do something like that. I had a big hole around 27-31km/h! By feathering the front derailleur, I found I could access 50/21 and 34/14 which bridges the gap just fine, but
a) I don’t think it would be wise to spend a lot of time in gears like those, and
b) managing rolling hills requires a great deal of shifting or a huge swing in cadence.
Having experienced this, I suspect that the 34/50 was never meant to be paired with an 11-23. I also suspect that 110mm bolt pattern cranksets are best used in mountainous terrain where you are either climbing steeper grades or flying.
"Having experienced this, I suspect that the 34/50 was never meant to be paired with an 11-23. I also suspect that 110mm bolt pattern cranksets are best used in mountainous terrain where you are either climbing steeper grades or flying. "
Yep, i’d agree. As a flatlander, i spend a ton of time in the intermediate gears, therefore the compact set up just doesn’t make sense. I can spend 1.5 hours in our tuesday road ride flicking between one or two cogs - and you soon realize, like you did, that it sucks to have a ‘cog-hole’ at speeds that you spend a lot of time in…
I use a 12-25 for everday riding (and racing for that matter) with my 50 ring. I get as far as the 21 on rollers, and that’s an easy chainline to maintain. I’m basically running a 7-speed 12-21 on the big ring. That covers a lot of terrain.
90 RPM. I am spinning a lot more than a few years ago, but I’m still not a 100RPM guy.
One thing that the compact could help me do is work on my cadence range (since shifting from a 50/21 to a 34/15 is so annoying), but I would rather do that by choice and not by (relative) necessity.
One thing that the compact could help me do is work on my cadence range (since shifting from a 50/21 to a 34/15 is so annoying), but I would rather do that by choice and not by (relative) necessity.
That’s a good point. Since I got rid of my cadence display and just started working based on power and PE, I have gotten comfortable at a much wider range of cadences. I used to freak out if I was “between gears” and couldn’t pedal at my exact cadence target. Now, I can ride at 75 rpm or 85 rpm with equal ease, and I shift a lot less.
Occurs to me that a 36 will close that gap up a bit…if its important…
Either that or use a 48 large ring (I think Dev Paul does that option)…either way will close the gap almost one “gear” and eliminate some of the shifting, if you find yourself needing that range a lot…and don’t like covering it with cadence shifts.
I recently set up with a 48/39 on 12-27. I’m definitely more of a spinner (90-100 on average) and this setup gives me plenty of overlap for those gaps that develop. After racing a very hilly Oly, I discovered I can probably get away with a 12-25. Otherwise, I think it’s a great setup for a flatland spinner. As was posted, you may want to try upsizing your small ring to bridge some of those gaps.
Been a roadie for a very long time and I love my compact cranks … on my road bike which I sometime ride in seriously hilly to mountainous terrain.
I can’t imagine why anyone would put one on a time trial or triathlon bike unless they were going to be in seriously hilly to mountainous terrain.
Someone posted here that they didn’t think a 23x11 cassette should be matched with a compact crankset. That’s exactly what SHOULD be matched with a compact crankset. If you don’t have the 11, you’ll spin out on just about any decent descent. And the 23 feels like a 25 or 27 with the smaller inner chainring, so you can save your legs on the longer, steeper climbs (if you need more than that, you should probably be considering a triple, anyway … or you just need to do a lot more riding) … and you can stay in the big ring longer without shifting down. But again, in my view, this is road bike stuff … not TT/Tri stuff.
34/23 is really close to a 39/26. Unless you are doing a flat TT where you don’t run afterwards, a compact is great for most. One of my buddies thinks the big ring is only for descending. A compact might be good for him.
Although if you turn over a big gear, you will not have as straight a chainline with a compact.
I will be selling my compact crank in the near future to go back to a standard crank. I do a few flat TTs and with a small tailwind a compact is not enough. I am a so-so cyclist too.
I agree with Psycholist. I live in Oregon where it is REALLY HILLY, well mountainous really. I have a compact that I love on the road bike that I just ride for training so the extremes of the range matter more than the gaps. Love having the 34/23 for big nasty steep stuff. But, on my tri bike, I run the standard 53/39 with a 12/25 for hilly courses and an 11/23 for flat ones. As an experiment, I took apart my 11/23 and my 12/25 cassettes and made an 11/25 for Pacific Crest which has almost ten miles of steep climbing followed by a 15 mile descent. The 25 was great as always for the climb and I was able to fly on the downhill with the 53/11. That was fun.
34/23 is really close to a 39/26
this is correct but the problem is (if you are referring to Campy set up) on the 26-13 cassette you are at a slight disadvantage compared to a 53x12 or a 50x11. Now I am a crap climber but decent descender and have to use everything I have on a descent to get back on to the pack in a road race. I have tried both the 53x13 and 50x12 options, neither satisfactory. I suspect different situation in a tri, where you might not need such a low gear (50x11 or 53x12). In a road race situation the only viable option is a 23-11 with a 34-50, unless its a really hilly race, then I will not be racing!
I disagree as well. I run a 50/36 on my TT race bike because I can’t turn over large gearings (53 x anything lower than 16) at low cadence very well. I’m super-uncomfortable in low cadences, and I spend most of my rides at or above 90 rpm. I go faster and save my legs for running on my 50-tooth big ring. I can also hammer up hills without shifting to my small ring, hills that I used to have to shift down to ride.
"I disagree as well … I can also hammer up hills without shifting to my small ring, hills that I used to have to shift down to ride. "
Probably part of the problem comes from our varying definitions of “hills” that we have depending on where we live. Where I live, most of the TTs and triathlons are in rolling terrain. We might have a 2 or 3% grade for a mile, but that would be the closest thing that would come to a “climb” and that’s not very close. So I run TT chainrings on my TT/tri bike and, like you, I spin above 90 rpms most of the time. But when I go downhill … I flat get it. I’m in 54x11 and the tears are flying out of my eyes … glasses and all.
An hour north of here, we have the front range of the Blue Ridge and you can do switch-back climbs from 700 feet elevation to 3,700 in 6 miles (what’s that? sustained 6 1/2 to 7%?). I don’t go there without my compact cranks. But I don’t go there with my tt/tri bike, either.
In fairness to all in this discussion, I should cop to the fact that I don’t run after the bike, either. I wish I could, but a teenage driver saw to that a couple of years ago. So running afterwards isn’t a consideration for me.
that’s why untill the current reincarnation, such gear combinations were called “alpine” gearing. it’s really great for going up and down really steep hills but the middle stuff is lost. no one will admit it but the the perfect flat to rolling triathlete gearing for most folks is probably a 50/42 11-23. let’s face it, you’re not drafting anyone, you don’t really ever ride slow, and you spend most of your time cruising along at a tempo like pace.
Blew out two achilles this past weekend because I just plain suck at figuring out gearing–either that or I am too lazy to drop down to the 34. Went round and round with patient Patrick tonight and still have no clue what I am doing, going to try out the compact crank one last time in a week and if it doesn’t make matters smoother I give up! The more I do the more Rookie I become. NOTHING feels right anymore…AHHHHHHHHHHHHHHHHHHHHHHHHH!
“Blew out two achilles this past weekend because I just plain suck at figuring out gearing”
Ouch!
It sounds like you are DEFINATELY a candidate for compact gearing. Darlin’, here’s the deal. Whatever gear you feel comfortable riding in, drop to the next easier gear … no matter what. Keep doing that and learn to spin easier gears at a higher cadence. Get comfortable doing that and build up your aerobic engine for a while. After you’ve been doing that for a season or so, start trying to go to bigger gears … gradually. You’ll find the muscle memory from the spinning will help you start turning those bigger gears pretty fast, too. And you won’t be tearing your legs up. And by then, you’ll have the lungs and capillary system to deliver the oxygen and carry away the waste.
