Bicycle Mechanics - 06 roubaix comp triple drops chain

I have a 06 Specialized Roubiax Comp (completely factory stock) with shimano ultegra triple front der and FSA crank set. 10 speed rear gear set. I cannot adjust my front der so that I do not drop the chain while shifting to granny low (inner most - smallest chain ring). I have downloaded shimano's derailleur set up instructions, and followed instructions using calipers to verify all dimensions in spec. Note: my LBS can't seem to adjust it either. Specialiazed tech support said some FSA cranks were a problem and may need replacement. LBS replaced FSA crank set - but the problem persists.

Problem seems to be in the inner derailleur adjustment. Shimano spec says inner chain stop should be from 0 to .5mm from chain (while on inner chain ring). After all other adjustents you should then tweek the inner chain stop for proper shifting. When inner chain stop in suggested starting position, the der does not move chain from middle ring to inner ring. Once inner stop moved in sufficiently to move chain from middle ring to inner ring, the chain stop does not stop the chain from over shooting the inner chain ring and sometimes it falls off, sometimes the chain doesn't settle into the gear cogs and rides on top, and sometimes the chain falls into place properly. The mis-shift happens 5 percent of the time with optimal adjustment. At this time I am frustrated, the kid (under 30) working on my bike at LBS is frustrated.

Has anyone else heard of any problems like this with the Specialized Roubaix Comp or Shimano Ultegra triple, or FSA crank set ???

thanks

misc notes:
* rear der always on innermost (largest) gear while shifting the front der
* inner chain stop more than 2 mm from chain once adjustment done to allow shift from mid to inner ring
* bike new 10/06, with less than 500 miles
* 10 speed rear gears (30 speed total for bike)
* problem happened since new, LBS tweeked adjustment for me a few times, but at first I thought maybe it was just me. However I can duplicate problem on work bench.

One of these will fix the problem assuming you can slide it far enough down the seat tube. You position it so it sits just next to the chain while it's on the 30t chainring and it works by nudging the chain back onto the chainring if it slips off:

http://www.bikemannetwork.com/biking/p/CH5800

I have one on an aluminum frame bike but was unable to fit one on a carbon frame because the seat tube is much fatter at the bottom due to the bottom bracket area reinforcement.

I'll be willing to bet that an Ultegra triple will work much better than the FSA triple. A friend has an '06 Roubaix Comp and I spent an hour or so trying to get it to shift correctly. In the end, it shifts ok but is no where near as crisp as the Ultegra triple on my RS and still throws the chain often enough to be really annoying. My Ultegra has thrown the chain to the inside once in the 3 months since I built it up.

If you insist on making the FSA crank work, pay particular attention to the alignment of the outside front edge of the derailleur cage with the large chainring during setup. I found that it has to be *exactly* parallel or shifting really sucks. Once you get it perfectly parallel, it just sorta sucks ;) The Ultegra crank is much more forgiving.

If you decide you would rather have an Ultegra 10-sp compact double setup, PM me.

Thanks for the help. My seat tube was too wide at the bottom for a chain overshoot device. I am having my LBS put on a ultegra chain ring. He says he can do it with the same carbon fiber fsa crank.
It's costing my $75.00 , but I figured - what the heck and I'm having him do it.

My LBS had a lot of problems with FSA cranks and FSA basically paid them to have Shimano cranks retrofitted to about a dozen bikes. There was a chainring spacing and configuration issue that caused the same overshifting problem you describe. Are you sure there is no overshifting device (Third Eye, Dog Fang or similar that will work?

I have an FSA compact double with DA drivetrain and was getting chain suck shifting to the 34t ring. I was able to adjust the FD enough to eliminate the problem. I realize yours is a triple and now doubt you have adjusted to a gnat's eye. Good luck

Consider contacting FSA and tell them your problem and that you are aware that they had a run of defective cranks. Maybe they'll replace your crank with one that works properly.

My 06 Roubaix T/C has 100 miles on it and won't shift correctly on the big ring. My bike shop has returned the crank to Specialized for replacement. I don't understand how these made it out the door.

gorditosan

* inner chain stop more than 2 mm from chain once adjustment done to allow shift from mid to inner ring


This part just doesn't sound right to me. If by "chain stop" you mean the low limit screw, I don't see how that adjustment can keep the derailleur from moving the chain from the middle ring to the inner ring. An adjustment to the cable tension could. The inner rail of the derailleur needs to be closer than 2 mm from the chain to keep it from dropping.

No, it doesn't sound right. The stop can prevent a shift to the outer ring if it's so close it won't allow the chain to catch the teeth. But 2mm seems like a lot. Maybe OP is measuring in the wrong place?

Is the dérailleur in plane with the rings? (Oh, I see that Proximo already mentioned that.)

Consider contacting FSA and tell them your problem and that you are aware that they had a run of defective cranks. Maybe they'll replace your crank with one that works properly.
Hello HillRider,
Thanks for the input.
Actually FSA replaced the middle chain ring. It is more like the shimano middle chain ring, that is, it's got a beveled profile on the side of the center ring toward the inner ring. This bevel profile sort of guides the chain to fall in place better on the inner ring. I just got the bike back from my LBS so now I need to put it to the real world test.

This part just doesn't sound right to me. If by "chain stop" you mean the low limit screw, I don't see how that adjustment can keep the derailleur from moving the chain from the middle ring to the inner ring. An adjustment to the cable tension could. The inner rail of the derailleur needs to be closer than 2 mm from the chain to keep it from dropping.

The way it seems to work is the cable tension is important to get to the middle ring from either the inner or the outer ring. But to get to the inner ring, the shifter just goes all the way to the inner stop. If the inner stop is not in far enough, the chain doesn't make the shift. If inner stop is too far in, the chain can over shoot and fall of toward the frame. on the Roubaix comp, this is the extremely delicate balance that I could not quite tweek in. But FSA sent m a new middle chain ring, so I will check that out this weekend. Thanks for the reply.

My 06 Roubaix T/C has 100 miles on it and won't shift correctly on the big ring. My bike shop has returned the crank to Specialized for replacement. I don't understand how these made it out the door.

gorditosan

I totally agree. the thing that really frosts me is that specialized wont fix the problem themselves, they told me to go complian to FSA. Well I didn't buy the bike from FSA - I bought it from specialized !!!!
Very VEry poor customer service from Specialized.

FSA was the one selling the mis-spected cranks. Specialized did replace the cranks until they ran out(The problem is the chainring, and how they are spaced, not the crank anyway)

Yes, FSA may have had a chainring issue, however, Specialized should have a quality control program to verify the specs of outsourced components. For example, If my brand new, in warranty Chevy had a power steering problem I wouldn't have to chase down Delphi or Borg Warner. Chevy would take care of it. Specialized should take responsibility for and stand behind it's products. Sluffing me off to their parts supplier is just plain irresponsible.