classic motorcycle forum
Motorcycle Discussions => British Bikes => Topic started by: iansoady on August 04, 2018, 04:41:45 PM
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My 1952 ES2 is fitted with an (incorrect) 1 1/16" Monobloc 376. It should be a 1 1/16" 276 type but I'm happy to stick with the later carb at least for the time being.
The "correct" settings for both the 276 and the 376 (which is correct for later machines) include a no 4 cutaway. I've found it runs much better with a 3.5 component although the only one I have in my fairly extensive collection of bits is well past its best.
It struck me that perhaps I could skim .030" or so off the bottom flat face of a good No. 4 slide which I have (I understand the numbers increment by 1/16" per whole number).
I appreciate this will probably ruin the slide but as they's knocking on £30 by the time VAT & postage is included I'm tempted......
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I think its just the angled side you remove metal from, and 1/16 strikes a chord in my scrambled memory.
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Ian, I've got a 376 3 1/2 slide. Pm me your address and I'll send it to you. I have no use for it.
Dave.
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That's very kind of you Dave. PM sent.
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I did find a thread on the Vincent forum where people do seem to have a fairly relaxed attitude to this sort of thing:
https://www.vincentownersclub.co.uk/threads/amal-289-throttle-slide-cutaways.8877/
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Hi Ian,
If you shorten the slide to reduce the cutaway the needle clip position will need to be moved the same amount
(if you have enough grooves to compensate)
Filing the intake side only will increase the cutaway, the opposite of what you want to do
John
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Thanks John.
I'd only be taking .030" off which is much less than the difference between any 2 grooves in the needle.....
I was going to skim the slide in the lathe so taking it off the flat end face rather than the angled cutaway so would be reducing the amount of cutaway.
That link I pointed to says that the geometry would be changed as the cutaway normally starts from the same horizontal position at the bottom of the slide hence its angle changes with different cutaway values.
But we'll see how the slide from Dave works.