Originally Posted by
cny-bikeman
1. No - the freewheel is removed and another screwed onto the threads with no need to replace the hub. that's why there's a remover for the freewheel. A freehub can be replaced as well, but the cog assembly is separate.
2. No again. If the derailleur is bent, corroded, the wrong capacity for the gearing, not compatible with the cassette/freewheel spacing, etc. etc. it will not function properly.
I would suggest in-person help at this point. Where are you located? There may be resources nearby.
1. Ah I see -- I thought that you could replace just the splined freewheel mechanism of a freehub without replacing the whole hub/axle thing. Is that not the case? Anyway, it's academic since my bike does have a freewheel.
2. The derailleur is in good shape, the gears spin freely, the hinges are smooth, and I'd be keeping the same # of gears. I didn't realize that it had to be compatible with the gear spacing, though; I thought the shifters took care of that. I had read elsewhere that derailleurs were mostly "dumb" pieces of equipment that were largely cross-compatible Thanks for the correction!
And yes, I have an LBS pretty near me and I will consult them. I just always feel better when I have an understanding of how things work and what my likely options are before I go into a store.
Originally Posted by
SkyDog75
For friction shifting, that's often the case, but not necessarily for indexed shifting.
With indexed shifting, each click of the shifter pulls a predetermined, non-adjustable amount of cable, which needs to move the derailleur the exact distance from one gear to the next. Because of this, shifters and derailleurs used together need to be designed for the same "pull ratio" ... I'm pretty sure your SunTour components use a different pull ratio than Shimano or any other readily available replacement components
Thanks a ton, I very much appreciate the specific mechanical breakdown.
I always like to have a "working model" in my head; it helps a lot in understanding what is or isn't likely to work and why.
I'll probably end up going with option 1a (cleaning) or option 2 if that doesn't work.
Option 3 is for if my friend feels like paying for extra parts