Page 1 of 1

Jet size

Posted: Sun Jan 15, 2023 9:41 pm
by Sb_750
Hello I have a 77 R75 and I it’s in the process of being a cafe racer I am planning on using velocity stacks. I want to know what jet sizeing I should go with. I originally have a 2.66 needle jet and a 145 main.
Also forgot to mention I will be using higher flowing exhaust. Don’t think it’s going to make as big of a difference to the jetting but wanted to point it out.
Thank you

Re: Jet size

Posted: Mon Jan 16, 2023 6:36 am
by SteveD
Welcommen.

One thing at a time.

Jets are cheap. Buy 150's and 155's. Experiment..
Raising the needle one notch is also an option. Which notch to start with?

Then there's plug chops to consider...

edit: I can't remember the name of the author but I think he used Dr. something as his name?
He does a systematic description of how to manipulate the carbs to suit.

Someone will remember the article...

Re: Jet size

Posted: Tue Jan 17, 2023 9:33 am
by Sb_750
Ok thank you I will get those and see how it goes

Re: Jet size

Posted: Wed Jan 18, 2023 6:57 pm
by SteveD
It looks like 48's are available too.

https://www.boxer2valve.com/bing-main-jets.html

Re: Jet size

Posted: Fri Jan 20, 2023 4:04 am
by SteveD