You need to make certain that 1)...your swingarm has the tab for the forward end of the support arm. and, 2)...that your frame has the tab to mount the master cylinder...the rest is just swapping parts. I'm reasonably certain your bike will have the necessary tabs...there is an early 80s R100 in my shop right now (with drum rear brake)...it has all the necessary tabs...photos to expalin:
Master cylinder mounted on its bracket:
Master cylinder mounting points on the frame...front tab on lower cross-member and right side muffler mount:
Master cylinder in place:
Tab on underside of swingarm:
Caliper mounting plate acts as a spacer between the shoulder of the axle and the rear wheel:
The support strut that prevents the caliper from rotating with the wheel:
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