Several years ago I was keen to try and improve the gear shifting feel on my airheads and after checking different oil grades and talking with an oil analyst I decided to try some LS90 weight oil ("LS" as in Limited Slip diff oil) I was very impressed by the improved smoothness and feel of the box. LS oil is not recommend in gearboxes where phosphor bronze parts (i.e.synchro rings) are used, but as our airheads have no p b bits I decided to test the theory.
After some distance and feeling very happy with the result I had a chat with a respected BM repairer only to be told he had come to the same conclusion himself. "Been doing the it for years
" he said. It is now in my drive shaft and final drive as well. Great stuff and good results.
"The only reason people get lost in thought is because it's unfamiliar territory"
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