I am the only owner/rider owner of my 1972 Combat Interstate Commando. My question is about the life of the cam chain and its sprockets. My Norton has ~ 50,000 miles and the chain has been kept in proper adjustment. The adjustment shoe is now approaching its limit with the adjustment still proper. I always keep fresh 50 wt Vavoline racing (conventional oil with a touch of zinc) oil in the engine. I put a personal rpm red line on the engine of 6,000 rpm since new and have never had a problem with the engine.
Has the reliability been an issue you with the Commando engines?
Get a new cam chain from Jason at The Chainman making sure to specify the Mercedes timing chain spec. It will last the longest and as it's already run in will not need a retensioning after 1000 miles.
Agree with John, A good time to renew. The chain must be in more or less ideal running conditions as I have never heard of a breakage, Mine (in a 99) is probably orriginal 60 years and 45000 miles ,suppose I had better take a look!. Easy to forget that these bikes need regular maintenance over and above changing oils. A bit more attention and maybe I would not be looking for new speedo drive parts .
The original chains fitted to Norton engines were endless but replacements often used to come split and supplied with a link. The design life for most Dominator engine components was 100,000 miles so theoretically you are only half way there. However do check the Camshaft sprocket for pointy or curved teeth as there is little point in fitting a new chain to a worn sprocket.
I'd be interested in the outcome. Some years ago I decided that, since I was going in to the timing cover, I'd buy a new cam chain so it would be to hand when I reassembled.
But the new one would not fit. It was bar tight. The mag chain and cam chain differ - but that was not the problem. Just possibly it was a problem caused by the packaging grease and maybe I should have washed it in petrol first.
But, anyway, I checked the one I had removed - for axial play etc - and it seemed to be in excellent condition. As it should be, having probably done about 25,000 miles. So I put it back.
Has anyone else had this happen? It was a Renold chain from one of our Norton suppliers.
Hi David,Think I mentioned this before . Its easy to fit the packing plates wrong so that adjustment very limited ,maybe only allowing used chain to fit.?.
I could not get the adjuster on at all! One day I might return to it, but not at present. The chain is endless, so both sprockets must come off - it's not just a simple case of unclipping it and clipping a new one. I lost a U clip on the road on my rear chain many years ago, so I often lock wire all of them if they are clipped (when I remember...)
The Reynolds chain in the blue and yellow boxes is distributed by THE VELOCETTE MOTOR CYCLE COMPANY LIMITED (yes they still exist but only distribute Brit bike spares), they buy the Chain in bulk from Reynolds, who want nothing to do with Motorcycles, and package them up for the trade. It is not the same chain as made in Manchester even though it is still made by Reynolds at one of their overseas factories. Best avoided especially the rear chain which seems to have elastic properties.
Renold allegedly left motorcycle chains because the application (passing 100bhp or more) through an exposed chain is far outside any rational performance specification for chain drives. So those who do sell for the purpose are comprising quality immediately.
hello well my Norton Manxman cam chains are untoched and are therfor original 60 years old and still like new but I have six set of spare camchains and maybe never get to use them yours anna j
Just replaced mine at 45,000. I have an automatic tensioner on mine, the sprockets are good and look unworn and I like to change my chains early, my rear drive chains are replaced when the adjusters are barely halfway. I got my cam chain from the chain man and that’s where the next primary chain is coming from in the not to distant future.