Main jet size? HELP!

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jasonrees
Posts: 3
Joined: Sun Apr 19, 2009 10:53 am
My Bike: zxr400 L98

Main jet size? HELP!

Post by jasonrees »

Hi all. I have only had the bike a week but thought i would give it the once over. Its an import around L4 i think. I have just striped and cleaned the carbs nad ready to check all the settings when i noticed the main jet size varies. 1 & 4 are running on 88's while 2 & 3 are running 90's. Is this normal ? Would i benefit replacing them for 95's as i thought 95's are the standard uk bike size.
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jake
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Re: Main jet size? HELP!

Post by jake »

sometimes you can run the inner 2 cylinders richer to help keep them cool..
It sound like you have the smaller import carbs on your bike with jets sizes that small.
I would measure them carbs, and if they are 30mm, then get yourself some uk 32mm ones.
jasonrees
Posts: 3
Joined: Sun Apr 19, 2009 10:53 am
My Bike: zxr400 L98

Re: Main jet size? HELP!

Post by jasonrees »

Thanks for the reply i will measure them later.
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RedexRobB
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Re: Main jet size? HELP!

Post by RedexRobB »

I have this exact arrangement on mine, i also have 30mm carbs. Got 32mm carbs sat in the shed waiting to go on!
jasonrees
Posts: 3
Joined: Sun Apr 19, 2009 10:53 am
My Bike: zxr400 L98

Re: Main jet size? HELP!

Post by jasonrees »

Bought some 32mm carbs of ebay. Replaced all the seals, reset the float heights fitted to bike and balanced them. definately a big improvement over the 30mm. Well happy!! Need to get a dynojet kit now and filter.
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