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Ok, here goes- please bear with the long winded explanation; I cannot understand why replacing a cassette has created a mismatch.
On One Big Dog; have been using it for years. 2x10, XT clutch mech. Hope Pro2 Evo hub, with extenders to fit the 148mm spacing and with shims on the brake disc to space it into line.
I've just replaced BB, chain, chainring and the cassette with a new SLX 11-36, all exactly the same as before. Except the old cassette was an XT..
The mech will not move over far enough to allow the chain to run smoothly on the 36t ring. it's almost there on the limit, just not quite settling.
Everything else is fine, the limit screw is right out and isn't touching its stop; the mech is simply incapable of coming across far enough towards the effective centre line. I've done changes like this dozens of times and never had this problem. When I measured the mech hanger (which is straight, I checked), its outside surface where it meets the mech is a full 9mm further outboard from the 11t ring of the cassette than the arrangement on my other hardtail.
The replacement cassette was new, boxed in the newer matt cardboard from Shimano and bought from a reputable supplier, BikeDiscount.De so I'd be very surprised if it was counterfeit.
Does anyone have any (sensible) observations or suggestions?
Did you have a space behind the old cassette which you now don’t have?
Did you have a space behind the old cassette which you now don’t have?
My thoughts also.
Has a spacer come off the hub attached to the old cassette?
Or is the spacer on the new hub in the wrong place (probably not, your shifting would be all over the place).
Did you take the end caps off the hub during the swap (unlikely or your disc would be dragging on the other side).
I don't like using extenders on axles for this very reason, the linkages on rear mechs only stay "in calibration" over a fairly small range, adding 9mm seems to be pretty high risk in any circumstances!
It's definitely a 10 speed cassette you're trying to fit?
As it's ten speed MTB, there's no spacer between cassette and freehub. I tried one anyway, to see if that's the problem but this then spaced the cassette too far out for the lockring to engage and tighten.
Nor is the freehub internal spacer out of position. The outside of the cassette at the 11t ring is just in the right place to allow the lockring to function correctly and the hub fits in the dropouts just fine.
The odd thing is that it was working just fine before. The BB spacers are as before as well; I did wonder if I'd got the chainring further outboard, increasing the cross in the chainline but it isn't that either.
Colin- Haha.. yes, I even counted the rings and the teeth on the rings!
Lol - I had to ask...
Put the old cassette back on. See what happens.
I did. And another, off another bike. Same issue persisted..
I got there in the end; the XT mech had a very slightly twisted main parallelogram, proven by taking it off and comparing to the articulation of another. It's nose, which should meet up with the business end of the limit screw, was fouling with the opposite frame before meeting with the screw. Hence not being able to get over far enough. Ho hum.. new mech ordered.
Thanks for the brain work folks.