Bicycle Mechanics - Front derailleur problems ... HELP!!

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I'm having a confusing issue with my front derailleur. I recently bought a Felt F35 - 2003.5 model. It has all ultegra except for the rear derailleur which is Dura Ace. The crankset is FSA Carbon Pro 39/53. Shifting fron the 39 to the 53 is smooth and fast when there is no pressure on the bike - i.e. when it is clamped into the trainer and the resistance drum isn't up against the back wheel. As soon as there is pressure - i.e. when I'm on it on the road or the trainer resistance drum is against the back wheel - the shifting is crap. It either won't shift up and the chain just grates against the inside of the 53 chainring without moving onto the teeth or I have to jam the shifter 2-3 times to get it to shift up. I adjusted the front derailleur and barrel adjuster 16 ways frrom sunday and so did the LBS and whilst it is now better, it still isn't smooth - it never goes on the first shift. I'm not heavy - 175 pounds. I have to shift once, release, and then push the shifter again. I've written (emailed) Felt about this, but have not received any reply. Why would pressure on the back wheel do this - is it forcing something out of alignment? Everything has been checked to ensure the proper tightness (cranks, etc.). I'm wondering if I should get the LBS to throw a different crankset on to see if that is the issue.
Cheers,
MacMan.
DieselDan
03-09-04, 05:21 PM
Lighten up your pedal stroke.
What cog are you in when you try shifting the chainrings? If you're all the way over in the lowest cog then the chain tension combined with the angle may be high enough that you can't shift up on the front.
Avalanche325
03-09-04, 05:30 PM
trainer resistance drum is against the back wheel - the shifting is crap.
Is this even when turning the cranks with your hand?
Is the shifter clicking? If you are shifting two or three times, the shifter is not indexing. If the shifter clicked in and the derailuer did not make the shift, you would not be able to click it again without shifting down first.
Rev.Chuck
03-09-04, 06:56 PM
Are the chainrings ramped on the back? Some are not and the 39-53 is a good jump, the ramps would make it much smoother under load.
Also, and this is unusual(for a new bike) but, make sure those two little pivot bolts (3mm allen, look at the rear of the der) are tight, they can really have an effect on loaded shifting.
Thanks for the replies:
1) I did actually try and "ease off" when shifting - didn't help.
2) I've tried shifting when in all the gears, just to see, same issue in all gears
3) The shifter does click over when shifting - but I then need to hit it a few more times to get the chain up on the 53
4) All bolts are firmly tightenend
5) I'm thinking the R1000 would have been better !... :mad:
3) The shifter does click over when shifting - but I then need to hit it a few more times to get the chain up on the 53
When you "hit [the shifter] a few more times to get the chain up" does the shifter have the same feel and response as the 1st time? Does it click with every hit? I am echoing Avalanche325 here - seems weird you can hit an indexed shifter repeatedly.
--J
georgesnatcher
03-10-04, 07:17 AM
Are you sure you are hitting the shifter hard enough and not going into the "trim" position. On my FD it takes some force to get it to jump up.
The shifter is definitely going all the way over - it is an indexed shifter but it is definitely travelling over the trim position. What happens is that I shift over and the shifter clicks into the full position and is locked there. I then let go of the shifter and then push it again - it barely moves but the extra force seems to push the chain over most of the time. I've looked at it in "slow motion" - I've had the bike clamped into the trainer and have the resistance drum up against the wheel. I then slowly turn the pedals and shift - the cage pushes the chain over but it seems to me that the contact point is quite low relative to the top of the chainring so the chain has a lot of travel between the two points. I've lowered the derailleur as much as I can to heighten the contact point but whenever there is resistance, it just seems to push against the inside of the chainring and not catch on any of the pick-up teeth - at least not smoothly. For $1800 I'd expect the shift to be a one-time affair. I know it won't be as smooth as a rear derailleur shift, but it should be going on the first try. Hell, my Trek 1000 shifted better on the front than this!!
I heard back from Felt this morning and per their advice will return to the LBS where they can call Felt directly. I'm going to test ride another F35 and see if the same issue pops up. The weather is getting better in Chicago and this is not what I need!
I appreciate all the good advice here - thanks to all of you.
YAY!!! Just got back from the LBS. The owner had called FSA and mentioned the problem. FSA sent a new chainring set. Problem solved - the bike shifts like a dream now. Just one push on the shifter and the chain pops up onto the top ring no matter what gear I'm in. At least it did on the 3-mile test ride! I will now wear a silly grin for the rest of the day.
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