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Kz750 twin backfiring
- 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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You should also check for vacuum leaks.
1979 KZ-750 Twin
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That sounds like a lean pilot system, either vacuum leak and/or the mixture screws are set too lean.Schmeck wrote: When you crack the throttle the bike sounds great until u let off the throttle and it will do a single backfire every so often .
Another thing: the 750 twins with BS-38 come with either 40 or 45 pilot jets which are too lean. They run much better with 50 pilots. The 50s stopped the "pop pop" when I let off the gas.
1979 KZ-750 Twin
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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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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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- 650ed
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1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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Do the weights move freely and smoothly?
Do the springs keep them in or do they wobble and flop around loose?
1979 KZ-750 Twin
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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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- 650ed
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1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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