Bontrager Front Derailleur Issue

kingroon

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Yo..

Having trouble workin out which mech I need to shift me big rings..

I have an old Race and whilst it's plain to see it's a bottom pull, because the routing kinda pushes the cables down the front/side of the seat tube down to a pulley just above the bb, it doesn't seem to give the front mech enough room to get activated? Get me? No, I'm sure I do either..

I guess this is directed at all Pre-Trek Bontrager owners.. What mech do I need? 28.6, top swing, bottom pull?? :?
 
You need a 28.6 top pull. The mech you have, however, is bottom pull so the pulley you see was fitted ( by the previous owner? ) as a compensator to fix this and shove the cable back up to the cable stop just beneath the seatstays at the back of the seat tube and continiue the top-route cabling standard of a Bonty.
Hope this helps.
 
can you show pics?

On my Yeti , i have a pulley as well and I have difficulties changing geras . the front mech does not seem to move enough .
 
did Shimano ever made a micridrive version ? because that could be the reason mine wont shift as i use it with normal rings ?
 
Chris,
no. But check your BB is 68/108 otherwise you'll get all sorts of shifting problems if it's any wider.
 
my BB axle is a lot longer than that . it is 120 minimum . I use a set of TNT straight cranks and even with such a long axle I nearly touch the frame .
 
Long shot and i don't even think it should make a difference but........
Does the cable just run round the pulleyto form a U shape, or does it pass down round the pulley then across itself to the mech. It would then look like a tear drop in shape.
Probably no difference, but might be worth trying before buying mechs ;)
 
I've had a closer look and I reckon I can just about make the cable go down the seat tube, then around the pulley [anti-clockwise] then up to the FD armiture, but it's gunna be close.. Real close..

Were the clamps on M732 mech thinner than those on the M737?

I'll get some photos on here later today, it does seem like a kinda crazy design [one of those "3am-I-gotta-finish-this!" decisions].. :?

Agency_Scum":2r9r49bn said:
Chris,
no. But check your BB is 68/108 otherwise you'll get all sorts of shifting problems if it's any wider.

Doh! I think I might have a 73 on it.. The Mech does seem stretched right out there on the adjuster screws..
 
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