Anyone racing a compact crank?
 

So, I need to make a dirty confession--My Flyte came with a triple crankset. It's nice because in the rare case that I'm on a hilly ride on a recovery day I can say hi to Granny and keep a low HR up a stupid-steep hill, but having the triple crank seems to lead to sloppier shifting with the FD, more extreme chain angles when I'm racing in the big ring, and more chain-dropping. I've never really cared about the image thing, so whatever.

I'm shopping around and have been looking at compact cranks. I feel like the 50/34 with SRAM's new 11-26 cassette would be a pretty sweet combination, with enough of a high end for sprinting and plenty of room at the low end to climb at a higher cadence on climbs without futzing with the triple.

Most of my races are crits, with the occasional RR. I'm NOT a strong climber just yet, so that's what makes the compact appealing.

Any compact racers out there? How's it working for you?

yea, i use a compact to race. 50/34 with a 11-23, somtimes a 11-21. works well, no complaints. there has only been 1 situations where i wish i had a 53-11. it was on very hilly road race and i was trying to bridge to the break on the decents.

there are alot of opinions on compacts, but i say go for it.

I race a compact. I've never been limited by the lack of fast gears in a sprint, and it has only helped me on the climbs.

Granted maybe women's races are a little slower, but I've also placed top 10 in a men's race with my compact.

I race with a 50-34 and 11-23. Top end is not a problem. 50x11 is higher than 53x12. I have yet to run out of gears in a sprint.

And I'd much rather have the option of spinning up the hills in 34x23. If you have a 26, you'll have crazy low end.

I raced on one for awhile. I have mixed feelings. I tended to drop my chain a lot shifting from the big to small rings. I guess they have the compact specific FDs now, so that could be overcome. I liked the broader range of gears for crits. The the fours they would slow down a lot so you would be overgeared in the big ring sometimes but undergeared in the small ring. You will turn more revoultions so your gears will wear out quicker.

I ended up switching back to a regular crank and that works for me. I have that compact on my cross bike with a 36/46 12-27 and that is just fine for that application. I got a third eye chain watcher and don't drop my chain either.

Probably the biggest argument agaisnt them for racing is that if you are down in the smaller cogs on the big ring, you lost efficiency. In the Bicycling Science book they found that bigger cogs result in greater efficency, probably because of the higher contact area. So a 53 will keep you in a bigger back cog and thus slightly higher efficiency. But this is a really small difference.

It sounds like for you it would be a useful change.

For another data point, I have dropped the chain once in about 700 miles since I started riding compact. That one time, I was going up a hill, and still managed to re-engage the chain without stopping.

Also, I'm using a normal FD. Actually, this is about the same rate I used to drop chains on my triple.

I've been racing with the stock FSA 50-34 that came with my Felt F2C all season from Cat 5 up to Cat 2 (so far :D ). I've been using a 11-23 on the rear in all races and have a 12-25 on my training wheels.
I've never had shifting problems in a race, and have had pretty good results this season.
5 wins, 6 2nds, 3 3rds, 3 4ths, 1 5th, 2 6ths.
I don't think I'll ever go to a 53-39, but I may switch to a 50-36.

edit: I wanted to add that I do go through a lot of chains (about every 1,000 miles). I think that climbing in the 34 puts a lot more stress on a chain than a 39.

I run a 50/36-23/11 for most races and 50/34-26/12 for one stage of the Ft Davis stage race (it has a 1/2 mile section of 17-20%). Most races in the Austin area have some pretty good rolling sections and short but steep climbs. I get better spacing with with the 23/11 rather than the 25/12 I'd be running with a 53/39 chainring set. Also I get a little better gearing on the top and bottom.

It would be nice if you put some numbers to this. Total power loss through the drivetrain is on the order of 1-3% and a lot of that comes through sideways deflection of the chain and drag in the derailleur jockey wheels (beside the bushing drag, the chain is going around two 9 or 10 tooth cogs right there). So of what's left for drivetrain losses, how much change can there be in going to the smaller chainring and cogs?

I've gone back to a standard crankset on all my race bikes. I'm running 53/39 or 53/38 with a variety of cassettes up to a 12/29.

I had a compact on my road racer/climbing bike and on my training bike, probably dropped the chain 5 times in a couple of years, using both standard and compact front derallieurs.

Funny thing is (in the "That's funny, my front door wasn't kicked in and I had a TV before I left home this morning way, not the ha ha way) 3 of the 5 times were in races at crucial times and cost me 3 top 5 results.

Still have one on my trainer, but I just am done racing with them.

Actually according to the tests published in that book (which I don't have because it was a loan) deflection accounted for minimal loss of efficiency. So while crossover has some other problems, efficiency evidently isn't one of them. The difference between efficiency in an 11 versus a 21 was considerable though, on the order of a few percent of possible power.

I've droped my chain about the same amount as I did on my standard set up, maybe once or twice. FWIW I'm using a standard Record FD.

Is your choice of running the 36 versus the 34 normally just a gearing choice or for shifting performance?

I've been running a compact setup since February - 50/34-11/23 after running a triple prior to that time. I've yet to drop the chain using a Record CT crankset set with Chorus derailleurs and brifters. I've only done one crit. Pretty much road races for me. When I was running the triple, prior to a race, I would set the lower limit screw on the front derailleur to prevent accidental shifting to the inner chainring. Most race parcours don't have insanely steep hills, so not having my lowest gears wasn't a problem.

Pretty ruff year eh pizza man...nice.I think he makes the case.

I have a buddy who's been racing with a 50/36 & 12-27 cassette...he had no trouble getting out of the 5s straight away. He's been a 4 for a while but it's not the compact that's holding him back :) PizzaMan's story is a pretty good counter to the Real Men Who Only Race With Big Chainrings. I say go for it, Doc.

Anyone know anything about what appears to be the new FSA Energy? I think they're selling at JensonUSA for $229 but there's no pic so I can't tell. These look SWEET. And 170g lighter than the SLK triple according to FSA's page... same weight as the K-Force compact!

http://www.fullspeedahead.com/fly.as...xid=21&pid=770

You the man Pizza! Wow and WTF. Great first year. Please tell me you are young like 25 and have raced MTB your whole life and delivered Pizza too boot. Sh1t thats just awsome.

Gearing choice. I don't run into any shifting problems with either chainring (34 or 36). For the type of terrain we have here in Austin I find the 50/36 11/23 set up to work the best for me. FWIW I made the decision to go to a compact after doing a test with my coach and we determined that I make my best and most efficient power between 90-105 rpm. Below or above those numbers I get less efficient and make less power.