robmcl

Last winter I rebuilt a 95 Marin MTB to be used for commuting and loaded touring. During the process I replaced the original triple crank, which was 94 BCD with a 42 or 44 tooth large chain ring. The new crank is the Nashbar Trekking crank, 110 BCD, 48,38,28. The rear cassette is 7 speed and I kept the original derailers. I installed a 118 mm BB and I recall measuring the chainline to be 44 mm. However, I have a problem with the chain rubbing on the front derailer cage both inside and out. This limits the number of cogs I can use on the rear cassette to two or three per chainring.

I am thinking that I need to get an FD that can handle a triple with the larger chainring. If so can someone suggest what I might need or is there another compatibility problem somewhere that I am not aware of? Also, if I switch the FD will I need to switch the RD? Although the cassette shifting has not been that bad.

I should also add that I use the original indexed grip shifters and all the components were Shimano STX.