No ,I can reface that part at work on a surface grinder.Its the outside diameter,that runs parrallel with the spindle.I have the dunstall tuning guide.Are you referring to the face of the boss where it would be up against the thackery washer?
If so, have a piece turned to the size of the spindle with a shoulder on it. You can use magic marker on the shoulder. Insert it into the rocker and turn it up against the shoulder. This will leave the high spots marked. File just the marked spots down. Draw filing would be best, so as to not round the shoulder of the boss. Repete this until the surface is all marked.
I don't know the size of the spindle, but you may be able to find a bolt with a washer face to use if you cant turn a piece to size.
PAUL DUNSTALL – NORTON MOTORCYCLES Tuning Manual c1970 • £49.99
PAUL DUNSTALL – NORTON MOTORCYCLES Tuning Manual c1970 - £49.99. FOR SALE! POOKS MOTOR BOOKS POOKS MOTOR BOOKS Click images to enlarge Description PAUL DUNSTALL – NORTON MOTORCYCLES Tuning Manual From Circa 1970 FORMAT: Stapled Manual, 32 Pages + Covers. LANGUAGES: English. ILLUSTRATIONS: Black...picclick.co.uk
I would have thought end for end weights were more important than overall. The center is irrelevant as it is supported by the spindle, only the ends are reciprocating.None. . . it's all done by eye and hand. BTW just make sure you remove equal amounts of metal from each pair of inlets and exhausts by weighing them.
A before and after dyno comparison, with no other changes, may never have been done, by anyone.In the UK at least opinions about this have varied. Gus Kuhn was adament should be left alone, but I once saw a set in a shop in Bexleyheath that looked like paper knives. Cant rememember his name but he claimed to have done sets for Dunstall
I totally agree that if you are going to take your bike near or to redline it's going to help keep things in place. But for most I think it is just one more thing you can do for no good reason. I bet my bikes have never seen much above 6,000 if that. Go ahead and roast me now.Watching Comnoz’ Spintron videos and the bizarre things that happen to the valve train at high rpm made me decide it’s a small price to pay for a little more peace of mind.
Are there things you can do to improve rigidity?Watching Comnoz’ Spintron videos and the bizarre things that happen to the valve train at high rpm made me decide it’s a small price to pay for a little more peace of mind.