Featured Knocking Noise Traced

Had a strange knocking noise most noticeable when manoeuvring the bike in and out of the garage. It definitely appeared to be coming from the gearbox sprocket area.
Whipped the cover off to investigate, and sure enough sprocket nut loose.

This is not an assembly error from the factory, what actually happens is play develops in the sprocket spines as they are just a push fit on the shaft, as the drive goes on and off this gets worse and eventually the nut must loosen as even the tightest torqued nut cannot withstand the tremendous radial forces and in the end it all comes loose.

Moral: check and re-torque this nut regularly, preferably using an impact wrench.
I decided not to use locktite as l wanted to avoid removal problems later on.
My bike is a 2016 with 16000 miles on.

 

Yes washer was there, not been disturbed from new.
As l said ,the problem appears to start because play develops in the spines.
If it happens again l will use locktite and tab washer and use heat to release it when l change the chain and sprockets.

 

Exactly right.....l had the same problem with my old MGB,once the spines wear it doesn't matter how much you tighten the nut the wheel will always come loose.

My current MGB has rostyles, wire wheels look great but they can also be trouble!