The X7 ones should fit shouldn’t they? £20 for the X9 ones, WTF is that all about?!!!

the bottom one should fit, the top one won’t.

Bugger, I have to pay £20 then for something that probably costs £1 to produce. GRRRRR.

i run x7 for this reason. sorry.

the bottom one should fit, the top one won’t.

Rubbish. Both guide and tension X7 jockey wheels fit fine in my X9 rear mech.

Why skimp on the only bit of the mech that touches your chain?

What’s the difference between the X7 wheels and the X9 wheels?

Hmmm, having just taken an X7 mech to bits, it does seem that the X7 jockey wheels should fit an X9 mech.

Does the X9 tension wheel have a bush or a roller ball bearing? I can’t remember as it was so long ago I binned the chocolate X9 wheel! I believe bushes are more suited to this application than ball bearings (and so do Shimano).

The X9 has a bearing, it does have a tendency to seize.

x9 has bearing in the pulley (bottom) jockey wheel, which seizes quite easilywhen I get mine off I’ll be replace that “one” with a shimano JW.

My X9 guide wheel has an offset axle hole, weird I know, but replacement JW that fit X7 ‘s don’t, hense why you need a specific x9 replacement ime.

OK maybe I should clarify: genuine Sram X7 jockey wheels and Sram X9 JW’s are inter-changable. I know because I have X7 JW’s in my X9 mech. It is the Tacx replacements that are flawed – the guide JW’s do not have the eccentric mounting and so don’t fit – whether X7 or X9 IME.