G: Gearbox (Twin) Double backlash

vibrac

vibrac

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Many many years ago must be early 60's (I was I remember in the Engineering apprentice school) I spent a couple of dinner times with a high speed air grinder taking out alternate internal dogs in one (or maybe two) Vincent gears. I know only a little Vincent lore now, but back then I knew nothing so I must have read an article in the Blue un or the Green un that gave detailed instructions( I know that was my source for the Norton clutch I fitted), anyway it worked and that old 1000 production racer changed gear a treat, of course now I am wondering if thats a way forward for our twin racer but in all the years of the forum I dont recall double backlash ever being mentioned and I certainly at this distance in time I cant remember the details...
 
Bill Thomas

Bill Thomas

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I think it was worth doing, Don't notice it being bad for the road now,
What I didn't like is someone said knock the teeth out with a cold chisel !!
Didn't trust myself !, So ground them out,
That and the Norton clutch made the quick changes safer I think.
 
T

timetraveller

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I agree with Bill. I did all my racing/sprint bikes by grinding, which took time but I was young. I too read about using a chisel but was not brave enough. I have used twins with double backlash on the road with no problems, as far as I am concerned, for years.
 
H

Hugo Myatt

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Bill Thomas said:
I think it was worth doing, Don't notice it being bad for the road now,
What I didn't like is someone said knock the teeth out with a cold chisel !!
Didn't trust myself !, So ground them out,
That and the Norton clutch made the quick changes safer I think.
Click to expand...
I hesitate to say it but I think it was PEI.
 
Albervin

Albervin

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I am intrigued by this. My Shadow has an early intermediate gearbox. Will changing the backlash help in gear changing?
 
H

Hugo Myatt

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Bill Thomas said:
I don't think I would bother for the road, It must shorten the life of the gears ?.
But when racing if you miss a gear, You could be hit up the rear ?.
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My C Rapide, purchased circa 1964 as a so called 'Creamer Black Shadow', (Mike Creamer, ex Vincent employee, latterly working for Lawton and Wilson, Southampton, had a sideline converting Rapides to B/S specification) had the high bottom gear and double backlash. I rode it on the road solo for forty years without any gearbox trouble. However I was never a particularly fast rider but a good deal faster than I am now. It was only when I fitted a sidecar that the gearbox became rather clunky so I reverted to standard Rapide gears. Hugo
 
Bill Thomas

Bill Thomas

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I think it must be the Ex L/ning that has the high first gear ,
If I pull away with not enough revs, I get a funny noise from the Engine shocker !,
Don't tell Vic :) .
 
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