I have a 2014 CR125. I bought an 18" Warp 9 rear wheel from a forum member who used it on his 2009 WR125.
When I mount it on my bike, it is fine until I tighten the axle nut. When I tighten, something binds. Initially I thought it was too short a center tube leading to pressure on bearings. When I removed the chain guide and brake pads to look more closely, I realized the actual problem - the rear disk is binding on the caliper mount.
The disk should be centered in a channel in the caliper mount. There is not a lot of clearance - disk is 4mm thick, channel is 6mm. All is well with the OEM wheel.
With Warp 9 wheel and axle nut finger tight, there is effectively zero clearance on the inboard/left side of the disk. The full 2mm clearance is on the right side of disk. As I tighten the axle nut, the disk starts to bind on the caliper:

The arrow in this photo more clearly shows the surface that binds against disk:

And disk is straight; it binds all around.
Everything I have read suggests the wheels should be compatible, so I am puzzled. It looks as though the disk needs to be spaced 1 to 1.5mm further out for my bike.
I am working with Warp 9 folk but wonder if anyone else has seen this problem and has a confirmed solution.
I wondered if the caliper had changed between 2009 and 2014, which might explain things. From parts catalog at Halls it is the same part number for assembly. Oddly, the picture in catalog does not match reality. From catalog:
and the actual caliper;

Not even close - catalog image has the slot on the caliper mount, while it is actually on the swingarm. I assume part number is updated and accurate, with image stale. But who knows...
When I mount it on my bike, it is fine until I tighten the axle nut. When I tighten, something binds. Initially I thought it was too short a center tube leading to pressure on bearings. When I removed the chain guide and brake pads to look more closely, I realized the actual problem - the rear disk is binding on the caliper mount.
The disk should be centered in a channel in the caliper mount. There is not a lot of clearance - disk is 4mm thick, channel is 6mm. All is well with the OEM wheel.
With Warp 9 wheel and axle nut finger tight, there is effectively zero clearance on the inboard/left side of the disk. The full 2mm clearance is on the right side of disk. As I tighten the axle nut, the disk starts to bind on the caliper:

The arrow in this photo more clearly shows the surface that binds against disk:

And disk is straight; it binds all around.
Everything I have read suggests the wheels should be compatible, so I am puzzled. It looks as though the disk needs to be spaced 1 to 1.5mm further out for my bike.
I am working with Warp 9 folk but wonder if anyone else has seen this problem and has a confirmed solution.
I wondered if the caliper had changed between 2009 and 2014, which might explain things. From parts catalog at Halls it is the same part number for assembly. Oddly, the picture in catalog does not match reality. From catalog:

and the actual caliper;

Not even close - catalog image has the slot on the caliper mount, while it is actually on the swingarm. I assume part number is updated and accurate, with image stale. But who knows...