Thanks Mike I'll try that.
On the stand I notice that when the plate displaces the
chain enough to get it off the small ring, the chain is
actually past the outer ring. With the 40 tooth that doesn't
happen. Be interesting to see what changing the angle does.
Bob
"Mike Jacoubowsky" <[email hidden]> wrote in message
"]news:[email hidden]...
Quoted message said:I swapped out 54/44 chainrings for 50/38. Followed Shimano
specs when I lowered the shifter. After making the change
the chain would repeatedly roll off the outer ring (i.e.
going from small to large ring). When I increase the size
of the middle ring to 40 problem goes away which
indicates
Quoted message said:I have the shifter adjusted OK.
Anyone know if a 12 tooth change is too much or is a
shifter that can
handle
Quoted message said:a 54 tooth ring too large for a 50 tooth ring?
Also wondering if filing down one tooth on either or both
rings might help the problem. Thought before I file I'd
check to see if anyone had
thoughts
Quoted message said:on subject
Don't file the teeth; that's not going to help anything. My
guess is that the angle of the derailleur is off a bit. In
general, when you're in the large front/small rear combo,
the derailleur's outer cage plate should be just slightly
pointed out at the back (away from the chain & wheel). Not
much, just slightly. You might have it parallel or even
inboard a bit, requiring that the limit screw be moved out
further than it ought to be in able to get it to shift up.
--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com
