NABodie

I picked up a 2013 Felt F-85 off craigslist and really loved the fit and handling of the bike from the first ride. I put some new tires on it to replace the cracking Vittorias that came stock on it. Everything was pretty sweet, except for the shifting. It wasn't terrible but every now and then it would jump off the cassette on the low end or not upstift like it was supposed to. Well I took it in to the shop who had it for a week and was told that they had done the best they could with it but that model Felt bike had an issue with the frame flexing slightly which caused the shifting problem. Now I have looked and looked but can't find anything documented anywhere that addresses any such issue. So I guess I'm calling BS on that diagnosis and will be looking for another LBS to do my repairs and adjustments. I haven't had the cables or cable housings replaced and have been wondering if they could possible be the problem? Thoughts?

alcjphil

A question: When you say that the chain jumps off the cassette on the low end, are you talking about the largest cassette cog? When it jumps off, does it jump into the space between the cassette and the spokes? If so, that is serious but I doubt that frame flex could have anything to do with it. If your low limit screw on your rear derailleur is set properly, and your derailleur hanger is straight, that should not happen no matter how much your frame might flex. Frame flex might cause the chain to move to a smaller cog, but that is not very common these days. You are wise to consult another bike shop. Do you know if the shop you went to replaced anything? That is important information. In particular, older shift cables can affect shifting, they should be replaced when needed, depending on age and how much use they have seen. Worn chains can also affect shifting, but often if chains are worn to the point where shifting is affected, your cassette may also need replacement. These are questions you can ask in the next shop you take your bike to

SkyDog75

What do you mean "jump off"? Would the chain derail past the innermost or outermost cog? Or was it just kinda skipping along the top of the cassette's teeth? (Different problems with different possible causes.)

You're right. Sounds like BS to me, too. Good call on switching shops.

Yes. Excessive friction from old/worn/gunky cables and housings can cause problems with sluggish shifting and indexing problems.

Andrew R Stewart 

[QUOTE=SkyDog75;20265433]What do you mean "jump off"? Would the chain derail past the innermost or outermost cog? Or was it just kinda skipping along the top of the cassette's teeth? (Different problems with different possible causes.)



You're right. Sounds like BS to me, too. Good call on switching shops.



Yes. Excessive friction from old/worn/gunky cables and housings can cause problems with sluggish shifting and indexing problems.[/QUOTE]


As can excessive flex of frame, hanger or slop in the der links/pulleys. There's a number of possible reasons that are not unique to any one frame that cause shifting issues.


The first step is to base line all you can. Andy

fietsbob

Felt is the brand, someone else ,makes the components they buy.. you bought a used bike and inherited other guis problems..


time to take it down to the local shop for a spring checkover/tune up ,

since I cannot see it in the from here to say anything from its appearance..

# 1 they can check the rear derailleur hanger alignment, those, bent are the root of many problems , shifting.


You own a book on bike mechanics yet?

NABodie

Thanks for the responses, the jumping off the cog issue has been resolved with a limiter screw adjustment. The chain would jump over the smallest cog to the space between the cog and the frame. Since it is time for a spring check up I'll have them check the derailleur hanger alignment and replace the cables and housings to see if that will take care of the shifting issues. Since I don't know Felts frame source for the 2013 F-85 frame I thought if it were that big of an issue on this model someone might have heard about it. As for books no I don't own one yet but am always interested in learning more. Suggestions are welcome.