81 kz650 front brake caliper swap from a 77 kz650?

recently i was riding home and my clutch cable snapped, not even 2 minutes later my front brake lost all pressure (i know they arent related) but apparently one of the brake pads fell out shortly after or maybe thats why the brakes went limp. i didnt notice this till after i replaced the clutch cable and took it for a cruise. so half of my caliper was grabbing the brake disk grinding into the caliper. i went to swap out the MC and caliper i have from a 77 kz650 but the holes on the 77's caliper were the same width apart as the caliper mounting bracket on my 81. is there any way to make this work? also if i try to line up the holes on the replacement caliper the top touches the disk. i didnt see any mounting plate for the replacemt caliper anywhere in all 6 boxes of parts. please help

You need to identify EXACTLY which model bike you own and which model 1977 KZ650 the parts are from. Some models came with dual front disks and some did not. Aside from the dual disk models having 2 sets of rotors and calipers here are other differences between the single and dual disk models that may effect your decision. Ed

With this list you can identify your caliper you Need.

The 81 KZ650-CSR caliper fork mount is completely different than the 77. see diagram drawings at Partzilla. I have no idea if the swap will work, but probably not. The csr is almost a completely different motorcycle than a 77 model & just about everything is different.

If the master cylinder is for a single disk, then it should work fine, but depending upon which mc it is, repair parts might be hard to come by.

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