TOPIC: Air box nightmare 1981 GPz550

Just got the new airbox on and the bike runs a hell of a lot better. Found out whoever rebuilt the carbs put #92 jets in when I take #94. Can I just switch them out without tuning the carbs?

Wow, that was a pain in the ass to get the airbox back on. Trying to deal with the cranckcase breather and getting the rubber boots on was an ordeal. Thanks for the link to the post on how to roll back the boots so they fit snugly onto the carbs.

So everything is installed, just need to step up the jets. Any help on this would be appreciated

Glad the tip helped! Welcome back to the world of airboxes! If they are Mikuni CV carbs I found this site very helpful. www.mtsac.edu/~cliff/storage/gs/Mikuni_B...Rebuild_Tutorial.pdf
Good luck!

They put in the 92, probably because that's all that is available in the rebuild kits.

To get 94's, you'll want Keihin small mains. Depending on your exhaust, you may want to go as high as 98. So if you are placing an order, you may want to get 94, 96, and 98. The numbers are the hole diameter in hundredths of mm. The Keihin jets flow slightly differently from the TK mains, but so slightly it's hard to quantify. Either way, since you are rejeting you will want to stick with one type of main to compare.

Here are the details on jets for TK-22's:

http://home.comcast.net/~loudgpz/GPZweb/TK22mainPage/TK22jetsAndDrills/TK22jetsAndDrills.html

Airbox successfully installed! What a PITA. Bike runs better now. No hesitation at low rpms anymore. Although I found whoever rebuilt the carb last put #92 main jets in. Would it be simple enough to go and install #94's in? Will it take significant tuning to get it to work? Thanks

Hey, could you send me a link or whatever it is you have explaining the cross compatibility of airboxes. I have a 1980 kz 550 and found a 1983 airbox on ebay. Based on your list I am optimistic it will work though I want to be sure.

In 1983 there were at least 5 Kz550 models in the U.S.
They are the Kz550 A4, C4, H2, M1, and F1.

Of those, only the C4 uses the same carbs as the 1980 model, so that is the only one you really have a chance of using.
The C4 was the chain-drive Ltd model.

(The others were the A4 standard, H2 Gpz, M1 shaft-drive Ltd, and F1 shaft-drive Spectre. )