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I bought an FSA carbon pro to replace my broken SLK. It's uses an ISIS BB, and it's not as stiff, but it is lighter. They're out of production but you can still find them.

There's the ZIPPs (really high end), and Stronglight Pulsions, which are both traditional BB cranks. Shimano's compact is an ultegra level deal and uses an integrated axle. It also has a much better system for connecting the left crank arm and putting the correct preload on the bearings. I'm not sure but I think it is pretty heavy. Extralite has some really spiffy looking integrated axle cranks for about $500, and they are very light, but I'm told they are flexy. Stronglight's come out with an integrated axle crank recently but I don't know much about them.
 

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Why not Chorus or Record? They can't be any more expensive than the K-Force, and they'll last longer than a few weeks. Record is lighter and has been measured to be stiffer, though I'm of the opinion that NO ONE can tell the difference between cranks of one "stiffness" and another, and it has the best bearings money can buy. Plus it has got the looks covered...

If you've got a Shimano bike, and don't want to "mix groups" (that's a stupid reason, for starters), Shimano's compact crank is pretty nice. Sure, it's aluminum, and it's a little heavier than DA, but it can't be much heavier than the FSAs, and at least it has real bearings and a mounting system that doesn't hang on Loc-tite.
 

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SDizzle said:
I'm of the opinion that NO ONE can tell the difference between cranks of one "stiffness" and another
I was too until I made the SLK-Carbon Pro swap. I can tell that the CP cranks (or maybe its the Ti BB axle) have some lateral give when compared to the SLKs, when I am standing on the pedals hammering up a hill. I don't think it makes any difference in my speed, it's just a different feeling. It's not good or bad, just different. These are on a Cervelo R3, which is a pretty stiff frame. On a less stiff frame the different feel might be less noticeable.
 

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I own six sets of integrated cranks. DA 7800. Truvativ Elita GXP. FSA Gossamer. Raceface Atlas. Raceface Deus. FSA SL-K. All integrated.

All of them at one time or another, four of them have suffered from the dreaded "crank won't stay tight" syndrome. Guess which ones. It's taken some time to resolve the problem on each, but I could get it to go away with various facing, shimming, and spacing strategies. Eventually it always came back, which is why the Elitas got replaced by the Gossamers (cross bike), and the SL-K got replaced with Dura Ace (road bike). Next time the RaceFace ones (mtn bikes) give me trouble, they'll probably be replaced by XT cranks.

Why? Because the Gossamers and the Shimano designs use one bolt to tighten up the system, and then pinch bolts to secure it all in place. That's the way to go my friend. Just having one bolt to bring it all together and hold it there (k-force, sl-k, truvativ, raceface, etc.) is a recipe for disaster, because it doesn't tolerate any variation in bottom bracket width. That's the bottom line, and I'm sticking to it. I'm not saying it doesn't work, because it will, but it requires more attention (periodic checking to make sure it's still tight) and quite a few more headaches than the gossamer integrated and shimano integrated pinchbolt designs...
 

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Couldn't agree more...

johnmyster said:
I own six sets of integrated cranks. DA 7800. Truvativ Elita GXP. FSA Gossamer. Raceface Atlas. Raceface Deus. FSA SL-K. All integrated.

All of them at one time or another, four of them have suffered from the dreaded "crank won't stay tight" syndrome. Guess which ones. It's taken some time to resolve the problem on each, but I could get it to go away with various facing, shimming, and spacing strategies. Eventually it always came back, which is why the Elitas got replaced by the Gossamers (cross bike), and the SL-K got replaced with Dura Ace (road bike). Next time the RaceFace ones (mtn bikes) give me trouble, they'll probably be replaced by XT cranks.

Why? Because the Gossamers and the Shimano designs use one bolt to tighten up the system, and then pinch bolts to secure it all in place. That's the way to go my friend. Just having one bolt to bring it all together and hold it there (k-force, sl-k, truvativ, raceface, etc.) is a recipe for disaster, because it doesn't tolerate any variation in bottom bracket width. That's the bottom line, and I'm sticking to it. I'm not saying it doesn't work, because it will, but it requires more attention (periodic checking to make sure it's still tight) and quite a few more headaches than the gossamer integrated and shimano integrated pinchbolt designs...
I'm not an engineer, but the design of the SL-K and other integrated cranks that rely on one bolt just seem like an accident waiting to happen. Mind you, I have 3 FSA cranksets, and my favorite is the Energy MegaExo. Aluminum, but has the benefit of the integrated BB and is solid as a rock. I love FSA stuff, but they don't have this solved yet.

I want to go carbon, but will be going Campy with the "old fashioned" square taper BB. Just waiting on them to go on sale with the introduction of the 2007 Campy integrated BB. For now, I am staying away from the carbon cranks with an "integrated" BB.
 

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johnmyster said:
Just having one bolt to bring it all together and hold it there (k-force, sl-k, truvativ, raceface, etc.) is a recipe for disaster, because it doesn't tolerate any variation in bottom bracket width.
Actually, the Truvativ cranks do tolerate variation in BB width. The left-side bearing has a sleeve permanently pressed into it, and when the bolt is tightened down, this sleeve is pinched between a shoulder on the spindle and the left crankarm. On the drive side, the spindle floats freely in the bearing.

After everything is tightened down, you can even loosen the drive-side bearing cup a few turns without any resistance (until it hits the crankarm).

I think I heard on this forum about Truvativ cranks that continually loosened up which were covered by warranty -- something about a manufacturing problem -- but I have two sets and a friend has a third, and we've had no problems.
 

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As I tried to mention in my first post:

The FSA gossamer integrated cranks that I have also use the separate pinch bolt design.

I'm holding the truvativs, and don't see anything special about them.

Here's an observation for you. Back in the day, shimano patented octalink spline pattern, and didn't allow anybody else to use it, which spawned the creation of ISIS. However, they did license the pattern to FSA, who created various carbon and aluminum cranksets that fit octalink bottom brackets. Eventually they licensed it to ritchey, also...

I think the same thing is going on here. Shimano must have patented the pinch bolt setup, and didn't let anybody but FSA license it from them. Problem is, you can't really do that with a carbon crank, so FSA has only done it with their alloy setups.

Just a guess on my part - but I still feel like the pinch-bolt setup is the way to go in the realm of integrated cranks. Note, also, that my road bike has made a technological reversion to a dura-ace octalink bottom bracket. Why you ask? Because that's the kind of bottom bracket mister SRM demands. So as much as I like the DA integrated cranks, they're still sitting on my closet shelf at the moment.
 

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cthomas said:
I want to go carbon, but will be going Campy with the "old fashioned" square taper BB.
Me too. My DA 7800 cranks are getting tossed for some Record carbons/Record BB (130 bcd, though - not compact). I don't really care about the carbon. I just think they're nicer than just about everything out there, including DA 7800 (and THM Claviculas, which don't exactly look like they're made for the 400 mile weeks I've been putting in...).
 

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johnmyster said:
I'm holding the truvativs, and don't see anything special about them.
The difference isn't obvious unless you know what to look for. If you look at the non-drive-side BB cup, you'll see that an aluminum sleeve has been pressed into it, giving it an inner diameter of 23mm (I think). The drive side cup, on the other hand, has no sleeve and an ID of 25mm. If you were to put the BB on the spindle and tighten the bolt, you'd see that the drive side cup slides freely but the non-drive-side cup is fixed tightly.

The FSA and Shimano pinch-bolt design has no sleeve on the NDS and the bearings in both cups has an ID of 25mm. I don't know how the single-bolt FSA design works, or the Race Face, though...

In the image below you can see the sleeve (brown) in the NDS bearing and the shoulder on the NDS of the spindle.


johnmyster said:
Shimano must have patented the pinch bolt setup, and didn't let anybody but FSA license it from them. Problem is, you can't really do that with a carbon crank, so FSA has only done it with their alloy setups.
From what I've heard, the pinch-bolt design patent was held by Bullseye and Shimano just waited for the patent to expire before making the same kind of thing.
 

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Another Option

cthomas said:
I want to go carbon, but will be going Campy with the "old fashioned" square taper BB.
I had this pair of Storck Power Arm carbon cranks and Phil Wood square taper Ti BB installed on my Trek OCLV. I was really happy with their stiffness until it developed a creak that I couldn't vanquish. I wanted to go compact, and was able to win a set of SLKs on eBay for a really good price. Once I installed them, my bike gained close to half a pound in weight. Overall I’m happy switching to FSA compact, but it did result in a little weight penalty. Maybe I’ll get some Zero Gravity brakes to compensate. Now, that’s a good excuse. :)
 

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Stronglight

I've been running on a Stronglight Pulsion compact crank for the past 4 months, and I've been really pleased with it. The Pulsion is light and gorgeous; the only weakness is that it takes an ISIS bottom bracket, and research seems to indicate that they all suck.

I have a Stronglight Twister BB and it's been fine, but IMHO ISIS an inherently flawed design, and we'll all have to hope for better in the next design cycle.

No complaints so far about the Pulsion or the Twister, but in an otherwise heaven-sent bike the BB is almost certainly the weak link.

Good luck...
 
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