Hello all. Just found thread which is helpful as I am doing this conversion. Have the Ohlin's shock built for MC21. 302mm eye to eye with shock length adjusted to minimum. I am finding the swingarm downward angle is excessive so that the chain will not clear the top of the swingarm with the stock MC18 link plates. Also the lower eye of the shock is touching or very nearly touching the link arm without rider.

I also bought aftermarket plates designed for adaptation of the MC18 for 17" rear. They seem to increase the ride height even further when installed with the long sides of the plates pointing down (i have seen a picture showing it oriented with the long end horizontal). which way should they go? seems horizontal orientation will greatly increase the rising rate.

My question is whether to try MC21 link plates and link. If they leave the back end too low i can always adjust the length of the shock. the other option is to shorten the shock by about 5mm with an internal spacer.

Appreciate any direction here.