southpier

how much trouble am i in?

i bought replacements which the description said were correct for my application, BUT i was sent 12 tooth instead of the original 11 t (replaced) pulleys. i have been made aware there could be ghost shifting.

should i stamp my foot and send those little suckers back? or ride it out and see if there's a real problem?*

*and then send those suckers back!

Troul 

try them out, verify the performance, & report back in this thread with your end results.

If they don't bind nor wobble excessively, they might be a nonissue.

SpedFast

You may have to adjust the 'B' screw to accomodate the larger diameter, but other than that you shouldn't notice any difference. Some friends of mine put larger (read=more teeth) on their MTBs because they believed it limited chain bounce and improved shifting while bouncing over rough terrain.

Andrew R Stewart 

Slightly larger der pulleys won't change the indexing points that the der (and its pulleys) is told to line up with (as told by the shifter and cable). But adding pulley teeth has some of the same effect as shortening the chain while at the same time decreasing the gap between the guide pulley and the larger cogs undersides. The "shorter chain" might have big/big cog/ring combos issues and the lesser gap might have pulley knock ones. What will be the case on any specific bike I would be hesitant to make specific claims about till I tried the pulleys. Andy

southpier

i've got my fingers crossed. the chainrings shift no problem (on the stand) and thursday's predicted rain will give me time to get the rear derailleur's cable connected and given a few spins. if everything seems jake, i may even take the bike out for its trial run for '22.

KerryIrons

The only possible issue is if the upper pulley was just about to touch one of the cassette cogs, and now with the larger diameter pulley it is hitting. And typically that can be solved with the B screw. Beyond that there should be zero issues.

southpier

everybody is talking about this B-screw!

where might this alleged screw be located?

i ran the chain 'round & 'round by hand (crank) this morning in both chainrings and at the same time shifting the rear derailleur x hand and everything seems to be fine with the exception of a little, but consistent, vibration which i might be hyper-sensitive to since the pulleys i replaced were 7 years old and pretty worn once i actually looked at them.

thanks for the inputs through this ordeal!

jimc101

Depends on the RD, on the back (as you look at it, but which screw is which and does what will depend on the RD you have (you haven't given any useful info like what you have, so no point in trying to guess)

SoSmellyAir

Does using a one tooth larger tension pulley interfere with the bent tab (which acts as a guard) at the lower end of the rear derailleur's inner cage plate?

southpier

no; as noted above everything seems to whiz right 'round with no hang ups. tomorrow when i attach the shift cable we'll see if that changes anything. forecast is for 1 1/2" of rain, so no time trials. and the kayak i ordered last august came in today so friday is probably not a ride day either.

the derailleur is a Shimano Deore XL (i think i've got that right - and i'm too tired to go back down to the garage and check. pulley wheels were Shimano Amazon.com : Shimano Deralleur Part Pulley 105/lx/deore 5700 Pr Upr&lowr : Sports & Outdoors.

SpedFast

If you can push the rear DR all the way in towards the spokes and the pulley wheel doesn't hit up against the largest cog, don't worry about the 'B' screw.