If your bushing OD is too small,You can chuck up the bushing in a lathe and lightly hit it with a knurling tool to increase the OD
This cheat will not work on heat treated materials, hardened races ...
We had 2 identical M135s (that were in sequential serial number order) 5 mph's apart MPH 40 and 45 the slower one had a lot of headshake, so I always believed it was safe speed of the individual vehi ...
WOW! The noobs first post
If you downsize your tips you can help a weak air compressor along but you will spend a lot more time blasting, and plugging tips ,I think my compressor is making around 19C ...