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jet advice

1133 Views 7 Replies 7 Participants Last post by  RedBird
hi there
i'm installing TORs this winter on a 2003 bonnie (790cc) with AI removed, unifilter installed but snorkel still in place.
I've thruxton needles that I can install if necessary.
Any suggestions on the likely jet sizes needed with or without the thruxton needles?
I understand that TORs come with a set and it may be possible to specify which size upon order.
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Check here:

Jenks Carb Tuning Guide

Go to page 10. This will give you a good starting point.
Pat's calculator is pretty neat! The down side is that you can only calculate what size main jet for particular needle/pilot set up. It doesn't help you determine the best set up for your particular intake/exhaust setup.
That's why I like the Jenks guide. It gives you a good starting point for almost any setup, then you can either go with that or get it checked out on a dyno and fine tune it some more.
The other thing on the calculator is that I don't see anything to select your displacement, so I would assume that it is for 790cc engines.
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