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Kz750b tuning.
- Stocky
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Can't get fine tuning correct.
I have a rebuilt 79KZ750B. 2into 1 Mac exhaust. Checked valve timing twice , ignition timing also. New carb kit , new diaphrams , carb stripped and cleaned twice . No air leaks. Checked float levels etc etc. continually fouls plugs - black sooty.
Have had running reasonably well - some intermittent missing, However I read a forum a while ago that suggested going to 50 pilot jet.. since then more fouling and more missing past idle. Also Adjusting pilot screw doesn't seem to make a lot of difference.
Can any one who has Mac 2 into 1 pipes tell me what jet changes are necessary.
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- Tyler
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I would then double check your work in the carbs. The BS carbs used on the twins are kind of odd balls.
There is a great write up here you should read through....
750 Twin Carb Info
My only experience with a MAC exhaust was using the 34mm carbs with three jets. I had to increase the large pilot jet and that was it. The MAC will lean the bike out a bit but not too much. You may need to go back to 40 pilot jet. The bike should be lean with that exhaust and stock jets, a fouling issue indicates a problem somewhere.
If I knew what I was doing all the time life wouldn't be any fun.
'80 KZ650 E 700cc, dyna ignition and coils, frame up restoration, daily driver
'81 KZ1300 A3 full restoration, custom big bore pistons, 1400cc 6 cylinder super bike
"77 KZ650 B1 - Barn Find, work in progeress
"74 Yamaha DT 400 Enduro
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- JWKZ750
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Stocky wrote: Hi Everyone,
Can't get fine tuning correct.
I have a rebuilt 79KZ750B. 2into 1 Mac exhaust. Checked valve timing twice , ignition timing also. New carb kit , new diaphrams , carb stripped and cleaned twice . No air leaks. Checked float levels etc etc. continually fouls plugs - black sooty.
Have had running reasonably well - some intermittent missing, However I read a forum a while ago that suggested going to 50 pilot jet.. since then more fouling and more missing past idle. Also Adjusting pilot screw doesn't seem to make a lot of difference.
Can any one who has Mac 2 into 1 pipes tell me what jet changes are necessary.
FWIW my 77 750B had a slow leak in the brass carb float. Till it was identified, I was going crazy trying to figure out what my issues were.
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- Stocky
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