I've got a 97' Trek 8200 and I will be replacing the crankset and bottom braket soon. I'll need/want to replace the front derailleur becasue it mounts to the bottom bracket. I need a bottom pull, but I've seen a SRAM online that says "twin pull (top and bottom)", is that either way or both? None of the others I've seen so far have indicated whether they are 7/8 speed or 9. Any help and/or input would be appreciated. Specs don't seem to be available on the manufacturers' websites for low end componenets. Seat tube is 31.8mm.

Thanks, Bill

Some derailleurs have top and bottom pull capability. The way you mount the cable is set so that you can route it around a mechanism or not so to either pull from the top or bottom.

What is the seat tube diameter? You should be able to replace the derailleur with a standard clamp on derailleur instead of the BB mount derailleurs.

Thanks, if I've got that straight - the SRAM derailleur will work either way.

Seat tube is 31.8mm and I am looking for a clamp on but there doesn't seem to be a big selection of bottom pulls and like I said the ones I've seen, other than the SRAM, don't say if they are 7/8 or 9 speed. I think I'll just buy the SRAM and not worry about doing any more fishing around.

A front derailleur doesn't really care how many speeds you have at the rear. The only difference may be that the derailleur cage width is different between models to account for different chain widths. You might have to do a bit more derailleur trimming at the front as a result, but it should work ok.