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Kz750 twin carb / throttle problems
- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- bountyhunter
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The bogging down and losing power sounds like you have crud filtering down from the fuel tank blocking amain jet. been there, done that.Schmeck wrote: Hello, So I was riding my Kz750 twin up and down the road testing out the new kenda tires I bought when all of a sudden my bike doesn't want to go. I would be in 2nd or 3rd { any gear really} and it would bog down every time I touched the throttle. It would do this until it shuts off . Then I go to turn it on and when I get it on it revs up at around 4 rpm and stays there until I turn the idle down. I read that the high auto rev could be throttle cables so I am going to see if I can adjust them even though they don't have any sharp bends in them . As for the bogging and it getting touchy and shutting off while I'm doing 40-50mph , I have no clue. Is there a magic spot I have to find on the idle screw to fix these problems? Also I am running 1.5 turns out on the tiny screw on the side ( which is stock ). I also have a shorty muffler which is not to shy from running the pipes straight. Just for additional information, My bike doesn't like to idle for more than 3 minutes unless the idle rpm is at atleast the 2. Anything below and it wont be long before it cuts off.
The "high RPM hang up" is usually a vacuum leak problem if not a binding throttle cable.
Running straight pipes means it is probably running way too lean.
1979 KZ-750 Twin
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- 650ed
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If at all possible, use carb cleaner rather than WD40. It will definitely reveal carb holder leaks and will not leave an oily mess all over your engine. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- slayer61
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- KZR FLAG RELAY CARRIER #62
Don't be ridiculous! It's only a flesh wound!
[strike]Wife's little bike... 1984 GPZ 550 Kerker and DynaJet stage I kit[/strike]
Wife's BIG bike......[strike] 1981 GPZ 1100 Kerker and [strike]factory FI[/strike] Mikuni RS34s W/ K&N pods[/strike] SOLD
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- bountyhunter
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My twin runs better with 50 pilot jets. The 125 main is standard, I have no idea if it is sufficient for the pipes you have. You may need to raise the needles a bit if you have poor throttle response at low end (?)Schmeck wrote: My main jet is a 125 and the slow jet is a 45. Should I go up in jet size because of my exhaust . My bike lags ever slightly on low end power.
All of that stuff is trial and error. On mine, the needle slots are about .020" apart so a full notch is a big step. I got some small steel washers that fir the needle which are .010" thick for a half slot step.
1979 KZ-750 Twin
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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- Schmeck
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1979 kz750 twin -Soon to be roadworthy
1988 El250 engine in custom hard tail frame - collecting dust
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