Cervelo P2 - FSA Gossamer/Energy Crank versus Ultegra 6700

In the interest of full disclosure, the guys at the bike shop are very nice and I like doing business there. They want to go the extra mile to make sure the customer is happy. They have a great shop, great product selection, etc.

The proof is in the pudding, and you can see shifting using the ultegra crankset is nearly flawless, whereas the FSA would likely cause a wreck at high speeds if you weren't careful. It seems clear to me on this particular frame that the FSA Gossamer crank, for whatever reason, doesn't perform well. It would be good to see Cervelo address the issue rather than leave it to the shop to try and make a bad solution work.

The new Ultegra crankset completely resolves the issue. I read on Cervelo's page that some felt the stay for the derailleur mount was 1mm too high, but I don't see how that would matter, as the lever arm and the chain ring ramps, when run on the middle ring in the back, push the chain up the same way. Regardless, in this case, if you have a Cervelo P2 Ultegra from 2008-2009, and are having nasty shifting in the front, chances are you will resolve your problem replacing the FSA with Ultegra.

Category:

Sports

Tags:

• cervelo
• P2
• fsa
• gossamer
• energy
• crankset
• ultegra
• 6700
• bad
• sloppy
• shifting

[esobucks]

I just got a used soloist and it appears to have a similar issue with an FSA gossamer front compact crank. I can shift into the larger front ring fine, but have bad chain rub in the small ring at the front in the 5 largest cogs on the back. I can't seem to find a fix at all, and am wondering if going to a standard crankset would fix. Where did you find your info that some cervelos had a possible defect in the front derailleur mount? Thanks

[sippervixx]

@esobucks - it wasn't a defective mount, it was that the brazeons were mounted too high on the frame, preventing the front derailleur from being lowered enough to meet the proper cog/cage spacing on compact cranks. I found it on the Cervelo forums, but have since lost the link.

[nicholasiantyson]

I'm a long distance Triathlete Colorado, I used the Ultegra for a full season & then upgraded to the FSA NEO PRO crankset. The fsa your showing sound like the distance between the ramp is off. I know because my cross bike did that same thing after I'd landed on it after my 7th jump. My old 2008 Cervelo P2-SL can handle both models, Ride safe, & ride hard

[sippervixx]

@nicholasiantyson - unfortunately due to the location of the brazeon where the front derailleur mounts, I canot decrease the distance any more. If I raised it up it got even worse. Thanks for the comments!

[recon455]

How did you account for the difference in distance between the two chain rings(FSA and Ultegra), if you didn't adjust your der. for both? Nice video nontheless.

[sippervixx]

The derailleur was as low as it would go. I measures the spacing first with pennies, but then with a set of dial calipers. The difference was almost non-existant, but it's the design of the ramps on the outer ring on the Ultegra that I think make it work so much better. I have since found out from Cervelo that there was a manufacturing defect in that model of frames that sometimes resulted in my problem. The issue is the braze-on that holds the front derailleur doesn't let it go low enough.

[sunhaoting]

@esobucks

1 possibility is the chain ring combination of the Gossamer crank in this video is 9 speed and definitely isn't compatible with Ultegra 6700 which is 10 speed.When Shimano first introduced new 10 speed system, many riders used FSA old 10S version which caused the bad shifting performance as well.Shimano definitely has no problem because it is the rule maker. It's impossible that Cervelo use FSA crank if its shifting performance just likes this video. It's out of the quesdtion,rght?

[sunhaoting]

@esobucks

1 possibility is the chain ring combination of the Gossamer crank in this video is 9 speed and definitely isn't compatible with Ultegra 6700 which is 10 speed.When Shimano first introduced new 10 speed system, many riders used FSA old 10S version which caused the bad shifting performance as well.Shimano definitely has no problem because it is the rule maker. It's impossible that Cervelo use FSA crank if its shifting performance just likes this video. It's out of the quesdtion,rght?

[coopsollini]

I've got the FSA Gossamer, with the pro chainrings like you, and it shifts perfectly every time.

[Seamaster42]

I had the exact same result swapping out my FSA SL-K light for an Ultegra 6700. The FSA shifted just o.k. and the the new Ultegra crank shifts better than anything I have owned. My shifters, front and rear derailuers (Dura-Ace 7800) needed no adjustment after the swap.