carb rejetting

[kwaka]

I want to attempt rejetting my carbs on the Z1B ( If needed ) but not sure how to determine what jet size is required. The engine has 70mm carbs, 4 into 4 exhaust with no baffles ( not popular with the neighbours ) . I'm not sure whether the cams are stock or not. I'ne done all the timing, mixtures and synchronising but it still sputers and i'm worried about running too lean. Is it just a matter of trying larger or smaller jets and see how it runs or is there a more sophisticated diagnostis method for checking?
Cheers

[Pasc]

Get it on the dyno to find out how its fueling throughout the range.
70mm carbs ? You sure ?

[sweptail]

70mm? They will take some jetting. Tc

[CRISPY]

Could have problems with small children being sucked in if you dont run air filters

[Pigford]

Air filters... ..... Gonna need a large roll of chicken wire for them

[Geoff Meager]

KIN ELL...is there enough room under the tank .....

[kwaka]

Quickest way to get a response is post a ridiculous blunder That was meant to be 70mm pistons ie the 900 has been bored to 1000 cc. Everything else is accurate i think. So any suggestions on how to rejet myself? i dont have access to a dyno either.

[FER]

Try 125 main jets and move the circlip on needle down toward pointy end one groove . If really worried about running lean go up one size on pilot jet and adjust air screws to suit .





fer

[Pigford]

Sorry for that Kwaka, but you asked for it

Std or K&N air filters

If std, the jetting shouldn't be far out on jets, maybe up a size or two

K&N type, then = 10 - 15% on std (120 - 125 )

But as you say, aim a bit rich to start, then its a bit of playing around

[kwaka]

Thanks for that, it will give me something to start with, I guess i can keep an eye on exhaust residue and plug colour.