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#844981 04/03/21 2:34 am
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Probably jumping ahead a bit but I've got a pile of lightning and thunderbolt heads to choose from for my motor build. Previously I've been running the lightning setup and been happy with it. Between my lightning and my mates thunderbolt there is marginal difference though, besides mine having a little more pep off the light. I was planning to go with a thunderbolt head for the simplicity of a single carb however I REALLY like the twin carb setup. Just feels more sporty even though I know it's marginal. Now the question is what difference would running a 932 single as opposed to the 930 make? Single 932 vs single 930? Single 932 vs twin 930's?
I tried a forum search cause I'm sure this has been asked a hundred times but didn't see anything. Anyhow.. thanks!!

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standard it's a 28mm carb on the t'bolt.
Makes a flexible nice riding bike, go up on carb size, why?
My one is good for a ton, although it's a bit slow up there after 90.

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As Nick said, if the pennies are tight I’d fit the 930, but if I do have or can afford to get a 928 you’ll find it will make it a much better bike.


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Originally Posted by Allan G
As Nick said, if the pennies are tight I’d fit the 930, but if I do have or can afford to get a 928 you’ll find it will make it a much better bike.

You’re likely to end up buying jets and slides, trying to get a bigger carburettor to work.

As well as wasting fuel on many many test runs.

And then buying a 928.


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I think the OP is thinking of performance.

Running one 928 will give a more responsive motor in the lower to midrange where you spend most of your time.

The bigger the carb the more airflow you need to make it work

If winning race the to the ton is imortant, go twin. If you want a nice rider go one 928.


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From my experience, a larger flatslide Mikuni will function well at lower speeds with the correct jetting...Larger as in a few MM..
Also from my experience, every properly tuned dual carb Triumph I rode seemed to have sharper throttle response above 3000 rpm than any single carb carb....But I never roll the throttle faster than the engine's ability to accept more throttle....


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+1 on the 928 - I spent ages trying to get a 930 jetted and set-up right but it never worked smoothly across the rev range whatever I did.

The 928 on there now works a treat!


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Originally Posted by triton thrasher
Originally Posted by Allan G
As Nick said, if the pennies are tight I’d fit the 930, but if I do have or can afford to get a 928 you’ll find it will make it a much better bike.

You’re likely to end up buying jets and slides, trying to get a bigger carburettor to work.

As well as wasting fuel on many many test runs.

And then buying a 928.
Ha! Noted.

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Originally Posted by Richrd
I think the OP is thinking of performance.

Running one 928 will give a more responsive motor in the lower to midrange where you spend most of your time.

The bigger the carb the more airflow you need to make it work

If winning race the to the ton is imortant, go twin. If you want a nice rider go one 928.
Thanks!


Moderated by  Allan G, Jon W. Whitley 

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