Front derailleur problem with compact crankset

hynesie

Hi all,
I'm having some issues setting up my front derailleur on my Focus Cayo 105 which has a compact crankset. When I first got it the chain would only shift to the big ring if I stopped pedaling for a second and then started again. But then as the weeks went by the chain began to fall over the side more and more until it was happening about 1/2 of the time I shifted up.

I figured it was as a result of some cable stretch on the new bike so I tried to adjust the top and bottom stops to fix the problem, but I could not get it setup correctly. I never had any problems adjusting the front derailleur on my old Trek 100 which had a standard double.

I dropped the bike into my LBS and they got it setup a bit better but said that the problem was with the gear shifter and if I wanted to do some racing on it that I'd have to get it replaced. Now it refuses to shift to the big ring about 25% of the time but at least the chain isn't falling off anymore. The gear shifter is a combined double and triple shifter, which seems a bit odd to me, it doesn't seem to be the most efficient solution to have both combined into to the one shifter.

And so to my questions:
* Has anybody experienced any problems with these weird shifters?
* Are compacts more difficult to setup than regular doubles?
* Could anything else be causing this problem?

Nietzschean

if the LBS says the shifter is b0rked maybe talk to wiggle about a return/fix/repair under warranty? how old is it? if its pretty new you shouldn't have to adjust anything with the limit screws as far as i know? normally just maybe some cable tension?

hynesie

Nietzschean wrote: »

if the LBS says the shifter is b0rked maybe talk to wiggle about a return/fix/repair under warranty? how old is it? if its pretty new you shouldn't have to adjust anything with the limit screws as far as i know? normally just maybe some cable tension?

Yeah, its still under warranty, bike's about 2 months old.
I've been on to wiggle already and they said to send back the shifter. But I don't want to get another double/triple shifter if they are the problem. Has anybody else had issues with these?

SetOverSet

Nietzschean wrote: »

if the LBS says the shifter is b0rked maybe talk to wiggle about a return/fix/repair under warranty? how old is it? if its pretty new you shouldn't have to adjust anything with the limit screws as far as i know? normally just maybe some cable tension?

+1
If your LBS mechanic has had a look and can't sort it, I'd give Wiggle a shout, explain the situation and see what they suggest...

Chips Lovell

Anytime I've had a compact, I've found the shift isn't as smooth as with a double, which is mainly down to the greater difference in chainring sizes. This usually meant having to "clutch" a little while shifting, i.e. soft pedalling or stopping pedalling while moving the shift lever.

hynesie wrote: »

I figured it was as a result of some cable stretch on the new bike so I tried to adjust the top and bottom stops to fix the problem, but I could not get it setup correctly.

You should be tightening the cable, not adjusting the limit stops to compensate for cable stretch.

hynesie wrote: »

The gear shifter is a combined double and triple shifter, which seems a bit odd to me, it doesn't seem to be the most efficient solution to have both combined into to the one shifter.

I think a lot of Shimano groups are set up this way, such as 105. Haven't read any reports about the combination being an issue.

I'd be a little sceptical for the moment that the problem is in the shifter. If it's possible to shift enough to throw the chain off the other side, then it seems to be working fine.

If I had to guess, I'd say that:

a.) Neither you nor the shop have set up the front deraileur properly.

or

b.) The crankset you have just isn't that great in terms of shifting from one ring to another. For example, I've found that Shimano's own compact cranksets shift a bit better than FSA for example.

hynesie

el tonto wrote: »

Anytime I've had a compact, I've found the shift isn't as smooth as with a double, which is mainly down to the greater difference in chainring sizes. This usually meant having to "clutch" a little while shifting, i.e. soft pedalling or stopping pedalling while moving the shift lever.



You should be tightening the cable, not adjusting the limit stops to compensate for cable stretch.



I think a lot of Shimano groups are set up this way, such as 105. Haven't read any reports about the combination being an issue.

I'd be a little sceptical for the moment that the problem is in the shifter. If it's possible to shift enough to throw the chain off the other side, then it seems to be working fine.

If I had to guess, I'd say that:

a.) Neither you nor the shop have set up the front deraileur properly.

or

b.) The crankset you have just isn't that great in terms of shifting from one ring to another. For example, I've found that Shimano's own compact cranksets shift a bit better than FSA for example.

Thanks for that el tonto. I am also not 100% convinced that it's the shifter either, hence asking these questions. I've found a one or two mentions of the shifters causing a problem but not so many to suggest that it's a common problem.

In hindsight I should have adjusted the cable tension first before messing with the stops. However my logic behind that was to try and adjust the top stop in order to prevent the chain from falling over the side.

Chips Lovell

hynesie wrote: »

In hindsight I should have adjusted the cable tension first before messing with the stops. However my logic behind that was to try and adjust the top stop in order to prevent the chain from falling over the side.

I'd have another crack at it then. Get the cable good and tight. Then check the cable stop to make sure there's enough there to allow it to shift up into the big ring. If the set up is the issue, then you may get it working quite well. How well may depend on the chainrings themselves.

What crankset do you have, by the way?

You mentioned you plan on doing some racing? I wouldn't worry about this issue too much. If you are racing on a compact, you'll find that you'll be in the big ring all the time in most races.

Lumen

el tonto wrote: »

If you are racing on a compact, you'll find that you'll be in the big ring all the time in most races.

Is racing on a compact much of a disadvantage? Not an issue for me now, but my next chainset might have to last me until (if/when) I start racing.

Chips Lovell

Lumen wrote: »

Is racing on a compact much of a disadvantage? Not an issue for me now, but my next chainset might have to last me until (if/when) I start racing.

I'd say that at beginner level, it shouldn't be a big deal. 50x11 is actually quite a big gear and even 50x12 I'd say would be more than enough for most.

I'm on a double and the only time I used the inner ring in a race this year was the Stamullen GP.

I prefer the double for easier shifting and less of a jump between small and big rings, but if you are starting out in something like a club league, it may not be a huge priority.

hynesie

el tonto wrote: »

I'd have another crack at it then. Get the cable good and tight. Then check the cable stop to make sure there's enough there to allow it to shift up into the big ring. If the set up is the issue, then you may get it working quite well. How well may depend on the chainrings themselves.

Thanks for that el tonto, I'll give it a go after the club spin tonight. Does the chain tension effect the positioning of the stops or are the independent of each other?

el tonto wrote: »

What crankset do you have, by the way?

Its a FSA Gossamer Compact 50/34 Mega Exo.

el tonto wrote: »

You mentioned you plan on doing some racing? I wouldn't worry about this issue too much. If you are racing on a compact, you'll find that you'll be in the big ring all the time in most races.

Ok, cool.

Thanks again Tonto, I really appreciate the help.

Chips Lovell

hynesie wrote: »

Does the chain tension effect the positioning of the stops or are the independent of each other?

Presume you mean cable tension? If so, no it doesn't. A tighter cable will mean less shifter throw before hitting the limit though.

hynesie wrote: »

Its a FSA Gossamer Compact 50/34 Mega Exo.

I've had an FSA before and while the shifting wasn't appalling, you did need to ease back a bit to shift.

Hope this helps anyway.

hynesie

el tonto wrote: »

Presume you mean cable tension?

Doh! Yeah, thats what I meant

horizon26

I have focus cayo with compact crankset.I had a bike with a triple yeah i am a wimp,i think compact cranksets are like that.You just have to live with it.I wish you luck racing on compact rings let us know how you get on.:)