Just a quick post on changing the rear shock on my 2015 YT Capra CF Pro race. It's fitted with a Bos Kirk, which I'm swapping out for the Fox X2 with lock out (specially fitted to the 222x70 shock).
I emailed YT to get the correct frame bushing sizes and got the following response:
Unfortunately you can't use the X2 Shock on the CAPRA. We needed to change the rockerarm of the CAPRA in order to fit the X2 on that frame.
Fox has a 2 mm tolearance in length of their shocks, which can lead to damages of the frame, when the shock is too long. The rockerarm would damage the frame by hitting it.
The Specifications for the mounting hardware are:
22.2x 8 mm (frame) and 34,0x 8 mm (rockerarm)
I hope this information is helpful to you.
Actually this doesn't help that much. Both the Bos Kirk and the Fox X2 are a 222mm x 70mm shock, so I can't see why the rocker arm would be difference in each application.
Any way, I'm going to try the shock deflated and check for clearance at the top and bottom of the stroke. I guest it will depend on the actual tolerances for my Fox X2 as to whether it works or not. I'll post some pictures and my results once fitted so others in the same boat have something to reference.
A little further info here. Got this reply back from YT:
Unfortunately we can't offer the rockerarm separately.
The shock is too long in total, so it would be 224 mm instead of 222 mm. The rocker arm would hit the seattube. I don't know if this problem will show up, when you release the pressure of the shock.
The problem would show, when the shock is too long, so I guess in the top stroke or when the shock would be decompressing. Because of the length of the shock this would push the rocker arm against the seattube, when the shock is decompressing.
Pretty disappointing that YT will not sell the revised rocker arm!
In any case, I'm going to try the shock and see how I get on with it. If I do have issues, I found these offset bushes that should cure the issue.
YT were correct, the FOX X2 is between 3-4mm longer than the factory BOS Kirk. When you fit the X2 the extra extension causes the rocker arm just and I mean only just make light contact with the frame.
One offset bush will offset the mounting by 2mm, which I don't think will be enough. As such, I've ordered 2x offset bushes 34mm and 22.2, which should do the job nicely.