Whiny CP gearbox

[Pete.Silson]

When under load 2nd gear in my CP gearbox has become embarrassingly whiny (to the extent that a rider behind me commented on it). On disassembly I found the 2nd gear cog to be very slack on the lay-shaft...

2nd Gear Layshaft Bush 1a.mp4

(1001.08 KiB) Not downloaded yet

...and the teeth on the lay-shaft cog and on the main-shaft sliding gear badly worn.

Clearly I need to replace the bronze bushes on the layshaft, the layshaft 2nd gear and main shaft sliding gear but can anybody suggest a cause of this type of wear i.e. did worn bronze bushes cause the tooth damage or did something damage the teeth that caused the wear on the bronze bushes.

The first gear is worn similarly albeit not so severely but the 3rd gear and output gears appear fine.

Any thoughts welcome. Pete

[Roger Gwynn]

The wear on the teeth will cause the whine, I like it, my VA whines in 3rd. I have no idea why it would affect some gears and not others apart from some gears may be worked harder than others, usually 3rd as it will usually see more use and is held longer than 1st and 2nd. It doesn't look like damage from a foreign object but from wear.