Poor shifting on trainer
 

Hi all,

In an effort to supplement my training for the upcoming MS150 ride in my area, I tend to fit in some Spinerval workouts on my trainer during the week when I can't get out on the road. For some reason though, when my bike is on the the trainer my front deraileur never seems to shift very well. If I take it off the trainer and go ride outside it seems to shift well again. I'm not sure what info would be pertinent at this point. I ride a 2008 Cannondale CAAD9 R5. All cables were replaced about a year and a half ago. FD is Shimano 105, 105 Double and 10 spd rear cassette with Ultegra RD.

Just seems strange that it shifts well on the road and not so well on the trainer.

Thanks in advance,
Tim

Not sure in your case but in general a bike frame flexes more and differently when secured to a trainer. Assuming that this is the type that holds the rear axle in place the frame is forced to twist as leg torque alternates from one side of the bike to the other. Sometimes I worry about my bike frames when riding my fluid trainer. Rollers would probably be better for the bike but not necessarily for the rider. :(

Also be sure that the rd cable is not being pushed in an odd way by the trainer axle bracket when mounted

It may be easier to shift when riding on the road vs shifting on a trainer. Try to shift when your cadence is higher - say 85 - 90 rpm. Then try to shift the same gears at a lower rpm. You may find it easier to shift at higher rpm's.

That's par for the course. Bikes shift different when on road vs. on trainer. Usually it's not a huge deal. I say deal with it on your trainer because your road shifting is the most important.

The pressure applied to the skewers can move the RD out of alignment. Sometimes a little cable tension adjustment is needed to produce better shifting on the trainer, but then you have to put it back to the original setting when the bike comes off the trainer.