I have a CBR fox shock on my mc-21. It needs to have ride height adjustment. I don't know exactly what needs to be done to make it fit. It was on the bike when i bought it. There is about 15mm of threads showing on the ride hieght adjustment.

The Ohlins CBR shock that i put on my mc-18 need the top mounting hole opened up. Both the upper and lower bushings needed to be narrowed. It took the machine shop 45 min to make the bushings match the stock shock.

The Ohlins CBR shock is about 3cm longer than the mc-18 shock with the ride hieght adjuster all the way in (shortest over all lenght).
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