okay pony ithink the 82 would work on the 80-81 rotros ...with the only mod being maybe to shim the calipers from the forks...if im remembering right .....if you are back to square one the 80-81.....the dual piston calipers are not that huge an upgrade people make to much of that .....the 80-81 calipers are my favorite nrakes and respon to the steel beaided brake lines even better than the 82s will as they the 80-81 have bigger piston that rquire more pressure and the pads cover more of the rotor in a more even way ...the rotors are thicker and tougher,,,im not a fan of drilling perfectly good rotors that are hard to replace to say the least like many do ....the best mod one can do in my opinion is to run dual lines from the front master cylinder to the front wheel with steel braided lines .....if it was me thats what id do if i was going to spend money on my brake system some pistons and dual lines ......
as for bleeding when you get the lines hooked up and before calipers are installed on forks and rotors clamp the pistons all the way back in the calipers with c clamps and bleed the lines or fill the lines all the way to the calipers with the bleeders straight up ....then install pads and mount to forks and rotors ,,,this usealy works perfect for getting all the air out .....in this condition the 80-81 brakes are super good and plenty for our wings for safe stopping .....if i remeber right you can buy three sets of back brakes for your for your 80-81 as the pads are thicker than the front and will fit the front too i think ...i might be wrong there its been awhile since i did it......well i think thats all the opinion i have :hihihi: :hihihi: good luck pony on the brakes :mrgreen: