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Jetting Help - '78 KZ650 D1
- HerrDeacon
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My bike has (I believe) VM24SS carbs and the main jets are 102.5. So, I'm thinking I'm going to have to at least jump up to 105's?
Will cutting off the last six inches of the mufflers affect the jetting requirements at all? I'm not planning on changing anything inside the muffler, just cutting off the last half foot.
One other thing is that I'm not really sure how it's running now. I bought it before the winter and, since I never had my licence yet, I never really drove it to see how it ran across the full range. Seems pretty good from what I saw though.
I'll be ordering these from Z1 so while I'm at it, should I order the 105's and also the 107.5's just to be sure, so I don't have to order more?
Any help is appreciated.
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- Bluemeanie
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1980 KZ650F1, Bought new out the door for $2,162.98!
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- bountyhunter
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Will cutting off the last six inches of the mufflers affect the jetting requirements at all? I'm not planning on changing anything inside the muffler, just cutting off the last half foot.
Yes, look at the picture. On my stock mufflers drilled four 1/4" holes in the rear baffle plate which allowed a more "straight through" flow because part of the exhaust is not forced back into the small holes to exit the final rear pipe.
It got louder and it ran WORSE. Maybe I could have rejetted it, but I bought new headers instead.
1979 KZ-750 Twin
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- HerrDeacon
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Bluemeanie, I still haven't had an opportunity to cut the mufflers so I'm not really sure how much baffling I need to remove. I think I'll take your suggestion and order the two sizes you mentioned. At least I'll have them to play around with.
Thanks again.
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- HerrDeacon
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107.5 Large Round Main Jet - www.z1enterprises.com/detail.aspx?ID=54
110 Large Round Main Jet - www.z1enterprises.com/detail.aspx?ID=55
I couldn't find the 17.5 pilot jets on the site, do they carry them?
Thanks
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- wiredgeorge
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wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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- HerrDeacon
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Thanks again.
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- wiredgeorge
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wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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- HerrDeacon
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Thanks
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- Bluemeanie
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1980 KZ650F1, Bought new out the door for $2,162.98!
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- HerrDeacon
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- HerrDeacon
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Don't bother with the #107.5 mains... not enough difference from the #110s... get #110s and the #17.5 pilots. Call them and ask for them. They do have them in stock. You will probably also want to reclip the jet needle to the 4th slot although you didn't mention which jet needle you have. Cheers wg
George, I finally got around to taking the jet needles out to see what ones they were and where they were clipped. They are 5CN15's and are clipped in the 4th slot. Is is alright to leave them there for this situation?
Thanks
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