I have a 1980 R100T under restoration. It arrived with an K&N air filter. After reading Snow Bum, I purchased a new "thought to be OEM" from A&S Motorsports in Sacramento. The filter did not fit, though the fische number was correct. After much head scratching I took it back with questions about correctness. The parts manager finally came out from the back and said the 1980 was a single year concoction of air filter housing that required a special filter that was no longer available. The listed part #13721337080 doesn't fit.
Long story shortened, does anybody know where I might look to find an original or original copy filter the is NOT a K&N?