I have a mc18 with a 21 wheel and swingarm crafted on using what looks to be a mc18 shock (shorter than a 21 shock). Ride height is fine in fact maybe a touch higher than stock but it does use what look to be custom linkage plates,

Im guessing these have been used to give more ride height due to the loss in height from going to a 17" wheel from an 18".
The 18 shock fitted is past its best although i have a decent 21sp shock but its longer, will fitting some stock 21 linkage plates drop the height back down enough to use the longer 21 shock?
Has anyone else got an 18 with a 21 arm that can provide any info on it?

Hi drunkn munky.

I'm almost done with that combination of 21 swingarm and wheel with the mc18 shock swap.

I tried a bunch of different combinations of the stock mc 18 and mc 21 linkage plates with the 18 shock... all ended up with having the ride height way too high. In the end I needed to make a custom plate, similar to what you have, to bring down the back end.

From my understanding, the 21 shock is taller than the 18 shock. My guess is with either of the stock linkages, you'll be way too high in the rear. You'll probably need another set of custom plates.

I don't have a 21 shock, but was keen on getting one from Tyga... so if you work it out can you post the dimensions for the new plate?

Yes the 21 shock is taller, i got hold of some 21 plates but they made the ride height taller than what i have there. You cant see in that pic but the plates are engraved "NSR" and to my knowledge the conversion was done in japan so i assume the plates may have been a off the shelf kit produced there.

Problem is my 18 R model shock is like a pogo stick and in my opinion its a waste of money rebuilding it, id settle for a 18 SP shock and have that rebuilt and fettled but yet to find one. im not keen on messing with linkage dimensions to achieve the correct ride height of a 21 shock as that alters more than just height and i'll be into unknown territory with that.

Ride height is currently fine on mine so if you would like the dimensions of these plates just shout

Yeah, making custom plates I believe changes the suspension behaviour - stuff like lever ratio. I'm way out of my depth with that.

If you don't mind posting the dimensions of the plates you have, I could compare it with what I have.

cheers.