83 KZ750 shaft keihin pilots?

If not already done, might find some helpful info at the Sudco site.
www.sudco.com/

Here's a link to page 156 in the catalog:
www.sudco.com/Catalog37Digital/index.html#/156/
(Takes a few seconds before it appears on-screen.)

Good Fortune!

Already been there I am giving up on mains for right now cuz I really don't think they are gna help my problem. I am on Monday or Tuesday going to attempt to drill out my pilots. I am gna go up in small increments and test each one til it runs right. Then if I'm still having issues I'll try to find some mains. I am still thinking my problem is just pilots are too small. All of my problems are in the bottom end of the rpms. Do you know if keihin jet sizes are in .xx mm? Like my #35 pilot is .35mm? I need to know what sizes correlate to what mm or inches or # so I can get the right size drill bit.

Dude,do NOT try to drill out the pilots.It won't work.Been there,done that. Have you checked the ignition timing advancer? They like to get stuck in the advanced position.Also,the advancer weight springs wear out over time,and the timing advances way too much,way too soon. This was my problem,found it out after nearly a summer of pulling my hair out trying to deal with the carbs.Also,the Ethanol in the gas makes the 750 run poorly between 2500-3250.

I have the same symptoms between 2500-3250 rpm...

How do you know it is Ethanol related?

Did you manage to get NOS new advancer springs? Or just used stiffer ones?

havakaw wrote: Dude,do NOT try to drill out the pilots.It won't work.Been there,done that. Have you checked the ignition timing advancer? They like to get stuck in the advanced position.Also,the advancer weight springs wear out over time,and the timing advances way too much,way too soon. This was my problem,found it out after nearly a summer of pulling my hair out trying to deal with the carbs.Also,the Ethanol in the gas makes the 750 run poorly between 2500-3250.

Check and check

I've checked everything on the bike over with a fine tooth comb. Timing is advancing correctly. Air filter is stock, pipes are hollowed out, new boots on both air box and engine side of carbs. Carbs are completely spotless. float heights are set, carbs are in sync using a vacuum sync gauge, Valves are within spec, etc etc. It just stumbles and is running lean on the low end, anything below 2700-3000 rpms. They don't make ANY other jets than stock for this particular carb. The only thing I can get is stock pilots, and a 100 or a 105 main. both from Kawi only. I ordered a #77, #78, #79, and 1/64" bits. They were all waaay too small. I was under the impression from many other forum posts that Keihin jets were like this: #35 is equal to .35mm. Am i mistaken? Can anyone point me to what size a #35 pilot would be in drill sizes so I can step it up a notch.?

rboutin2 wrote: ...float heights are set...stumbles and is running lean on the low end, anything below 2700-3000 rpms....

float heights are set -- this hopefully means fuel levels are within specs as determined by the clear tube test.

The dry-measured upside-down float height adjustment is unreliable, and often produces incorrect fuel levels.

The correct float height is whatever float height -- regardless of its measurement -- produces the fuel level that's within spec as determined by the clear tube test.

Too low fuel levels (per clear tube test) may produce the symptoms described.

Good Fortune!

Yes. Float heights set with the clear tube method.

rboutin2 wrote: ...stumbles and is running lean on the low end, anything below 2700-3000 rpms....

Are o'rings on pilot adjustment screws in good condition (to prevent air leaks)?

Does application of choke reduce the stumbling below 2700-3000 rpms?

Good Fortune!

Pilot screw orings I Actually just replaced just to thrown out another possibility. The choke only helps if it brings the rpms above 2700-3000. Anything less with choke applied still runs bad.

Would suspect that low rpm stumbling due to a too lean condition in the pilot circuit would be improved by enriching the pilot circuit with application of choke.

If adding choke doesn't help it, seems like a larger pilot jet wouldn't help it either.

Good Fortune!

What are results of the compression tests?

Good Fortune!