Mikuni Tuning, Detonation
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Joined: May 2009
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From: The South
Is the purple VOES wire grounded or not connected to anything?
If the wire is grounded, your always on the high timing map, and if disconnected, your always on the low timing map.
Your timing may not be the culprit, but cant see not taking advantage of the VOES for street use.
If the wire is grounded, your always on the high timing map, and if disconnected, your always on the low timing map.
Your timing may not be the culprit, but cant see not taking advantage of the VOES for street use.
I'm wondering what Mikuni tuning kits people are buying that come with the widest variety of jets.
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From: la la land jerzey
i can also help i have used Voes switches and can send one with the back open so you can adjust it when you find the spot that works for you - buy the used one or buy a new one with the same inches of vacuum release -- you may need a 4.0 FXR type Voes
i also have every jet Mikuni makes in stock sooo if you need something odd i will have it
i also have every jet Mikuni makes in stock sooo if you need something odd i will have it
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From: Ohio
Check out the Joe Minton mileage kit for the Mikuni, used it as a base for 10-1 compression with early intake closing cam, Ultima ignition with no voes, can run it on the 2nd setting solo with my hair on fire throttle.
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From: The South
Can you, or anyone, shed some light on my air fuel screw mixture adjustment? At two turns out, idling properly using the idle adjuster, I cannot get the bike to die or sputter by screwing the air fuel screw in. It only increases RPMS. The tuning manual does not address this scenario.
In my mind, wouldn't this circuit be the slow speed jet that is too lean if I can't get enough fuel in to choke the engine?
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Joined: Apr 2011
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From: SE Louisiana
Did you happen to check for an intake leak?
My afr's read odd on the front cyl on my 111 when I got it, front intake seal leak, on a brand new engine.
Would have never picked it up other than afr's, no typical symptoms.
My afr's read odd on the front cyl on my 111 when I got it, front intake seal leak, on a brand new engine.
Would have never picked it up other than afr's, no typical symptoms.
Last edited by Schex; Jan 22, 2014 at 08:18 AM.
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From: The South
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Joined: Jan 2008
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From: Cleveland, Ohio
I don't have any experience with Mikuni carbs but general tuning would suggest that if you turn the mixture screw in and the RPM increases your low speed jet is to rich. When you turn in the mixture screw you are reducing fuel. If the low speed jet is too rich the RPM is increasing when you take away fuel added by the mixture screw by turning it in.
If the slow speed jet is correctly sized when you turn in the mixture screw the engine dies because it is not getting enough fuel. If the mixture screw is turned out too far the engine stumbles because it is getting too much fuel. In the middle of these points is were the engine should idle good.
If the slow speed jet is correctly sized when you turn in the mixture screw the engine dies because it is not getting enough fuel. If the mixture screw is turned out too far the engine stumbles because it is getting too much fuel. In the middle of these points is were the engine should idle good.
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From: Ohio
Turning the air screw in on a Mikuni leans out mixture and the screw also affects the low speed mixture unlike the CV. Mikuni also has the jet for the accellerator pump meaning that if your detonation is in the throttle roll on area, the pump can be a issue or raise the needle because the accellerator pump and needle can carry over to the high speed jet.
What rpm and gear is it rattling in?
What rpm and gear is it rattling in?