Hi
I noticed bronze in the oil on my commando and tracked it down(i think) to the camshaft bush on the timing side.
The oil below this bush had a reasonable concentration of bronze.
The cam turns smoothly and feels like a good tight fit(as far as i can tell) but there seems to be a lot of end float.
Its a 920 with 4s cam and a NRE crankshaft,skimmed head large valve RH10 head, which is all probably irrelevant 
, i did some work on the pistons/head gasket area, so it was standing for a while before i started it again, i did lube up the cam area during the rebuild though.
Any ideas how to get the the bottom of what is causing this problem?
Ive not split the cases yet, the bottom end is still in the bike
Many Thanks
ps Ive already fitted an oil filter.
Cam end float is minimal w…
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Previously simon_ratcliff…
Hi, if you look on OLDBRITS.COM, there are pictures of the various thrust washers and bushes. There is one type with a tag on it which breaks the tag off. It can chew up and get in the pump. Lots of info on access norton.com.Cam end float is minimal with the sprocket nut tight as required. If you have alot of end float then something is missing or unusually the timing side cam bush flange has possibly worn.
Hope that helps, Paul
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Thanks for the advice gent…
Thanks for the advice gents
I put the gear/nut back on and measured end float at 50 thou, which is slightly larger than suggested, there are 2 washers both without the tag, i dont think the tag was on originally (which it good)
I gave Les emery a call at Norvil who said that "Mr Nortons" suggested chain cam adjustment is too tight. reading up on theexcessivecam bush wear and the fact that there was bronze in the oil under this bush, ive now spilt the cases to check the bushes and any cam wear (which there is).
Ill take it off to Les to replace the bush(es) and examine the washers and cam for excesive wear
Thanks again and ill let you know how i get on.
Cheers Cliff
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Cam end float is minimal with the sprocket nut tight as required. If you have alot of end float then something is missing or unusually the timing side cam bush flange has possibly worn.