Hi can anyone give me a bit of advise?
I am doing a refurbish project on a 1955 Norton Dominator 88 twin Deluxe 500cc
This bike was last on the road in 1967, it was taken apart and never done anything with.
I bought the machine two years ago and have 99% of the refurb done. On putting the Cylinder Head on I noticed the tappet adjustment are all over the place, like screwed right out or in. When I got it, the tappets and pushrods were all out and in plastic bag and unmarked, also by looking at the chamfered edge there is three of one side and one of the other, will this matter? how will I work out the correct positions in order for the tappet adjusters to sit to the middle of the screw adjusters?
Once I have this problem sorted, I only have the wiring to go, the remaining other bits to go on are refurbed ready to go on.
Could anyone please advise, or should you require further information, then please come back to me.
Regards
Len Adams
Lateral Thinking
Jan is correct.....pushrods do tend to shrink with age.
However, you do need to check a few other things.
Have any of the valves pocketed the head? This being a familiar issue with well-used Dominator heads. Are the valve lengths correct for head. Post 1967/8 the exhaust valves were 0.10" longer.
You mention an odd set of followers.....If the engine has been run with these followers then one of the tunnels may have a strange wear pattern. Check out both tunnels.
You engine was built with round foot followers. Is this still the case? Or has a flat foot version been slipped into the bag of bits?
Back to pushrods....Your bike should be using the thin non-SS, all steel version with parallel shafts. 7.92" inlet and 7.08" exhaust lengths plus or -minus 0.10"
Is the cylinder head alloy or cast Iron? An alloy head needs alloy shaft pushrods to allow for the head expanding. The iron head is best using all steel pushrods.
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pushrod lengths are most likely culprits.
Tappets are not a matched set, by the sound of it. What state are the cam-facing surfaces in? Do they fit well in the tunnels? If using a new camshaft, they should be refaced unless in extremely good nick.