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Anyone have experience with the FSA Compact or similar 2 ring crank set?

The 50 - 34 jump is bigger than a 53 - 39 so I would expect more derailleur changes accompanying a ring change but, practically speaking, how much of a problem is it?

I think I want the wider gear range.

thanks
 

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I Love mine

I've had mine about a week and a half now, six rides total. I live in southern NM and have a choice of rides between pancake flat and mountainous right outside my door. I've actually been using two different bikes depending on which way I turn. My triple is a Tiagra set up with a 12-25 in back. My double was a 105 with a 11-21 in back. I put the crank on the double along with a 12-27 in back. Shifting has been fine and it gives me enough gears that I don't feel the need for the triple anymore, no matter which way I turn from home. Actually, for the last 2 rides I swapped out the cassette on the double so that I'm riding with the 50x34 up front and 12-25 in back.

Sure, I've lost a little in the top end, but I only really notice it during a long descent, when I'm gliding just a little more than I used to.

My triple is now a permenant back-up bike, and I may get an aluminium compact crankset for it.
 

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7% increase in range...

What you get is 6% reduction in the top gear and a 13% deduction on the low end for a net difference of 7%, which is a bit less than a typical 1-cog change (9%).

These setups often exceed the maximum capacity of the rear derailleur, which makes the chain length adjustment more critical and may make the little ring and one additional small cog unuseable.

Just how valuable they are depends on the terrain you ride (how much lower is enough?), the brand of equipment you use and whether your drivetrain is 9 or 10 speed.

For the price of a carbon compact crank and BB many bikes could be converted from 9-speed to 10 speed, yeilding a slightly larger increase in range.
 

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Not that clear cut

Not quite sure where you get your percentages. I changed from a 52x42x30 triple with a 12x25 cassette, to a 50x34 double with a 12x27 cassette. With 172.5 cranks my top end gain ratio went from 52x12 (8.4) to 50x12 (8.1) not that much of a loss to me (specifically 0.8mph at 60 rpm).

At the lower end I went from 30x25 (2.3) to 34x27 (2.4). Also not a significant change except for the fact that it's a double instead of a triple.
 

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Skinny Legged XC MTB geek
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Similar experience with Torquecal

I'm running the FSA 50-34 up front and an aluminum 12-27 in the back. On yesterday's training ride with a bunch of guys who will be riding solo in the 24hrs of the Old Pueblo next weekend, we put in 65 miles, including a major climb at the far point of the out and back. When it got steep, everyone else was out of the saddle groaning and straining to push their 39x25 and 39x23 combos. I spun right on by in the saddle using the 34x27 wearing a smile. In the flats, it made no difference.

However, on the part of the return trip after it was no longer too steep to pedal, but not flat, I got burned by the guys who had 53x12's and 53x11's to push. I couldn't keep up. So, what's the answer? It depends! On balance, we probably were equal during yesterday's ride; I had a climbing advantage and they had a descending advantage, but my advantage only kicked in when it got real steep. It is more likely you (and I) will encounter more long gentle descents where we are disadvantaged. Eventually, as I get stronger climbing, and can switch to a smaller cassette with an 11 tooth small cog, I will close that gap. I wish I could find an 11-25, but no one seems to make that combo.
 

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Not quite what I'm after

torquecal said:
PedalAZ, http://www.sheldonbrown.com/harris/k7.html#9cassettes has a custom cassette 11x28 that you might like. If not, they also sell individual cogs.
The 2 cassettes I have, a 12-27 and a 12-25 are CNC'd aluminum (by Recon), one piece bodies, and weigh only 111 and 114 grams, respectively.

Loose cassette systems damage aluminum hubs, especially the big cogs, and are heavier.
 

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broken calculator???

torquecal said:
Not quite sure where you get your percentages. I changed from a 52x42x30 triple with a 12x25 cassette, to a 50x34 double with a 12x27 cassette. With 172.5 cranks my top end gain ratio went from 52x12 (8.4) to 50x12 (8.1) not that much of a loss to me (specifically 0.8mph at 60 rpm).

At the lower end I went from 30x25 (2.3) to 34x27 (2.4). Also not a significant change except for the fact that it's a double instead of a triple.
The original poster mentioned a 53/39 as his original setup. My percentages are accurate with respect to the original post.

The idea that a triple is somehow a big disadvantage almost always comes from a Shimano user or somehone who has never used a 53/39/30 triple. STI levers don't have the versatility of Ergo levers when it comes to shifting a triple.

Apparently your calculator is broken. All your gear ratios are wrong. A 30/25 is a 1.2 ratio and a 34/27 is a 1.26 ratio. Your 34/27 is equivalent to a 30/24, which is nearly as low as the low gear on your triple with the 12-25, but you have greater jumps between cogs with the 12-27. You can't have your cake and eat it too.

With a Campy 10 speed drivetrain, 53/39/30 chainrings and a 12-25. You get a 16T cog, less extreme jumps between cogs, a higher top end gear and a lower low end (equivalent to a 34/28). The weight of an FSA triple crank and BB is identical to a Record double setup, so for the typical Campy user there is no weight penalty. There is no downside to this setup that I can see. When I climb mountains, I get into the little chainring as soon as the 39/23 is not low enough and never have a need to shift out of it until I get to the top.
 

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Thanks

Thanks for the clarification, I didn't check the math against the original poster's gearing.

As far as my calculator goes... actually I posted gain ratios (taken from Sheldon Brown's online calculator) not "gear ratios." I'm not up on all the math involved but it gives another repeatable number, other than gear inches, for comparison.

True, I've got greater jumps between gears, but in practice it hasn't been all that big a deal - for me anyway, obviously IMMV.

Actually, I have ridden Campy triples and I do have to agree with you on one point, they do seem to work much better than Shimano triples. My problem is I really really can't stand campy shifters :-(


C-40 said:
The original poster mentioned a 53/39 as his original setup. My percentages are accurate with respect to the original post.

The idea that a triple is somehow a big disadvantage almost always comes from a Shimano user or somehone who has never used a 53/39/30 triple. STI levers don't have the versatility of Ergo levers when it comes to shifting a triple.

Apparently your calculator is broken. All your gear ratios are wrong. A 30/25 is a 1.2 ratio and a 34/27 is a 1.26 ratio. Your 34/27 is equivalent to a 30/24, which is nearly as low as the low gear on your triple with the 12-25, but you have greater jumps between cogs with the 12-27. You can't have your cake and eat it too.

With a Campy 10 speed drivetrain, 53/39/30 chainrings and a 12-25. You get a 16T cog, less extreme jumps between cogs, a higher top end gear and a lower low end (equivalent to a 34/28). The weight of an FSA triple crank and BB is identical to a Record double setup, so for the typical Campy user there is no weight penalty. There is no downside to this setup that I can see. When I climb mountains, I get into the little chainring as soon as the 39/23 is not low enough and never have a need to shift out of it until I get to the top.
 

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But I am a climbing wuss

Jed Peters said:
Try an 11-23 or 11-21 and tell me that it doesn't make a difference in your spin.
and can't bear to part with a granny gear. That's why I am lusting for that elusive 11-25.
 

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Thanks for the info!

ovalmasterofmydomain said:
FSA now makes a compact alloy crank called the Energy Compact. Bulteksports.com currently lists it for $149.
Thanks for the info! Might have to come up with some extra $$
 

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pedalAZ said:
and can't bear to part with a granny gear. That's why I am lusting for that elusive 11-25.
No, I hear you.

I'm just saying for long days on the flats or crits, I really like my closed ratio cassette becasue it saves my legs.

My goal this week? 300 miles. All on the flats though.
 

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No problem at all

RUSA2392 said:
Anyone have experience with the FSA Compact or similar 2 ring crank set?

The 50 - 34 jump is bigger than a 53 - 39 so I would expect more derailleur changes accompanying a ring change but, practically speaking, how much of a problem is it?

I think I want the wider gear range.

thanks
Unless you are using friction shifters it is a total non-issue. I have been using a compact for several thousand km and I think the 50-34 actually lessens the number of times I have to change rings versus a 53-39 or 53-38.
 

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FSA Compact Crank Set

RUSA2392 said:
Anyone have experience with the FSA Compact or similar 2 ring crank set?

The 50 - 34 jump is bigger than a 53 - 39 so I would expect more derailleur changes accompanying a ring change but, practically speaking, how much of a problem is it?

I think I want the wider gear range.

thanks
I've had mine on an all DA Chisallo since Sept 03' and really like it. The cassette is a 12/27. I had the chain shortened about 2 links and the FD re-adjusted. No problems at all.
 
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