Ok, I'm coming to the end of the project and am just wondering about carbs.
Whats a standard main jet for the 4jh?
Has anyone run these open? (probably will put a 45ppi filter across, trapped by the tank)
If so, what main jet size did you end up using?
Also, is there anyone in the Peterborough area that could alter the exhaust for me (will pay of course)
Thanks
John

It's usual to use the 3TJ airbox cut and shut to the 4JH airbox holes.

You could try Preditor in Stevenage, they can make or adapt a link pipe

I know its usual to use the airbox, but am wanting to know what size jets are in the 4jh as standard, as I have 3 sets of carbs with 3 different main jet sizes. (118, 155, 165)
When racing zxr's we had really good results running the carbs open and blocking off the air correctors and am wondering if any one else has done this to save time and money on a dyno if it doesn't work on an fzr.

The standard sizes will be in the Document Library at the very top of the page - in the Service manual

Was hoping more for a "yes its a 1??" Kind of answer as I do everything off a phone with the internet and you would not believe how slow it can be to download something. And when it fails after 10 mins of waiting. ...well that just p!sses me off.

main jets 118.
Main air jet 80.
Pilot 45
Pilot air jet 100
Jet needle N1YA
Pilot screw 1-3/4 turns
Engine idle 1.250-1.350r/m
float level 11.5-12.5 mm

Sir, you are a gentleman.
Thank you.
:)

Glad to be of help.