Bicycle Mechanics - Ritchey WCS compact - LBS struggling...

Had LBS swap from Ultegra double crank to the WCS. Shop said it'd need a new FD. After two return trips, they figured out the problem was that the FSA FD they'd installed was a triple. Said they'd installed an Ultegra triple FD and it was working now. Picked it up and it's better but rubs the FD at either end when shifting out of the middle 5-6 cogs. Shouldn't this be a fairly easy installation?

Thanks.

Had LBS swap from Ultegra double crank to the WCS. Shop said it'd need a new FD. After two return trips, they figured out the problem was that the FSA FD they'd installed was a triple. Said they'd installed an Ultegra triple FD and it was working now. Picked it up and it's better but rubs the FD at either end when shifting out of the middle 5-6 cogs. Shouldn't this be a fairly easy installation?

Thanks.Are you using the shifter's trim feature to move the cage clear of the chain when it rubs? Also, if you trim the derailleur position with the shifter and it still rubs, check that the rubbing is really the chain on the derailleur, rather than the chain on the side of the big chainring.

Now why didn't they use your old FD????? It would have worked just fine with your new compact.....

Now why didn't they use your old FD????? It would have worked just fine with your new compact.....


+ Like to hear the answer to this.

+ that for me, too. The only possible new FD you'd need would be an actual compact-specific FD, and whether you actually need that is debatable.

I'm running a bontrager 36-50 compact crank with a 105 double FD. I only need to use my trim clicks when in the 36 ring and the smallest two cogs, or the 50 ring and the largest 3 cogs.

edit- is it a braze-on FD? perhaps they couldn't lowed your double FD enough to work with your small ring?

Big picture: unless this is Ultegra 10-speed, another idea is to simply plunk a DeoreLX rear derailleur, a wide-range cassette and a longer chain onto it, then put your Ultegra cranks back on. We've done several of those lately where I work.

I ran a Ritchey WCS with a Ultegra 6500 double FD and it worked OK....much better than the 6500 triple FD I had on there previously which resulted in a LOT of dropped chains. The double FD was better but I still had some dropped chains. When I moved to Campy I got a Centaur compact specific FD and it worked very well. My vote is for a compact specific FD.

It sounds like you meant they installed a FSA bottom bracket for a triple rather than an FSA FD. I don't think FSA makes derailleurs. If so, then your LBS did an incompetent job. The BB for a triple has too long a spindle for a double. Take it back and make him put the right BB and derailleur on your bike.

+ that for me, too. The only possible new FD you'd need would be an actual compact-specific FD, and whether you actually need that is debatable.

I'm running a bontrager 36-50 compact crank with a 105 double FD. I only need to use my trim clicks when in the 36 ring and the smallest two cogs, or the 50 ring and the largest 3 cogs.

edit- is it a braze-on FD? perhaps they couldn't lowed your double FD enough to work with your small ring?

With only a 14 tooth jump from 50-36, you would not need a compact specific derailer.

I have FSA's C-16 FD on my 50-34 compact and it has helped decrease the number of dropped chains since changing from the Ultegra FD. It might be mental or just an adjustment thing, but I am glad to have the FSA FD on the bike for that 16 tooth jump from big to little ring.

Thanks guys - that was a nice drivetrain crash course.

Yes, small chain ring and lowest 2 cogs the chain is contacting the back of the big ring. On the large ring and large cog, the chain comes in at too dramatic an angle to even use. From large to small ring requires a deliberate and forceful pull on the lever and produces a heavy clunk. My triple on another bike shifts better.

Trimming helps the other concerns. I, too, thought the double FD should work. I'd hoped to sort this out myself but will take it to another LBS and have them advise.

Yes, small chain ring and lowest 2 cogs the chain is contacting the back of the big ring.


That'll happen. That's big time cross chaining and you're better off going to the big ring.



On the large ring and large cog, the chain comes in at too dramatic an angle to even use.


Again, big time cross chaining. Shift to the small ring.



From large to small ring requires a deliberate and forceful pull on the lever and produces a heavy clunk.


Sounds like the FD is not adjusted properly. Could be the high limit is too tight. Is this on a 10-speed or 9-speed setup? If you're using a 9-speed cassette and chain, make sure they are not using a 10-speed front derailer. The cages on 10-speed FDs are narrower and getting them adjusted to work well with a 9-speed chain is near impossible.



Trimming helps the other concerns. I, too, thought the double FD should work. I'd hoped to sort this out myself but will take it to another LBS and have them advise.


I have two bikes with compact cranks, both 9-speed, one with a 9-speed double FD, the other with a 9-speed triple FD and neither have chain drop or other shifting problems. It can be done, don't let the shop sell you a bunch of stuff you don't need.

With only a 14 tooth jump from 50-36, you would not need a compact specific derailer.

I have FSA's C-16 FD on my 50-34 compact and it has helped decrease the number of dropped chains since changing from the Ultegra FD. It might be mental or just an adjustment thing, but I am glad to have the FSA FD on the bike for that 16 tooth jump from big to little ring.

Just to clarify- Wouldn't need it because the chain won't drag the bottom of the cage when in the small ring? Or something else? I was under the impression that compact FDs were also curved tighter to better fit the small circle of a 50-tooth chainring, and that this helped with not getting as much crosschaining rub.

On another topic, I fitted the Deda dog fang to my bike, and then set the derailleur to give very positive downshifts without fear of dropping the chain. Doesn't look as good, but looks better than a dropped chain or stalling on a hill because of not downshifting.

Just to clarify- Wouldn't need it because the chain won't drag the bottom of the cage when in the small ring? Or something else? I was under the impression that compact FDs were also curved tighter to better fit the small circle of a 50-tooth chainring, and that this helped with not getting as much crosschaining rub.

Good point. One thing I have noticed with the 50-34 compact and the FSA compact derailleur is that I don't have to use the trim at all to prevent chain rub. I can get all the way to crosschaining before hearing a rub in either the big or little ring. Whether this is by design on FSA's FD or not, I can't say for sure. I have to mentally remind myself not to get too far to avoid cross-chaining because the tell-tale noises just aren't there letting me know to use the trim. I try to keep it off of the farthest two (or three if possible) opposite cassette gears to keep wear at a minimum.

One of my favorite things about the compact paired with at 12-27 cassette is being able to stay in the big ring for virtually my whole rides and not having to shift up front. That's coming from a flatland rider, by the way. Having the little ring when we hit the hills up north is indespensible!