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Discussion Starter #1
I need to jet my carbs and I have a couple of questions (its been awhile)
How can I tell if its lean or rich?
Which way do I move the clip on the needle to get more fuel, and which way do I screw the air/mixture screw to get more fuel?
Thanks.
I'm running 36 Mikuni flatslides.
Main 120
Pilot 15
86 GSXR with an 825 bore.

[ 08-16-2002, 04:43 PM: Message edited by: suzukiltd ]
 

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I'll take them one at a time:

- telling whether you are lean or rich? Two methods that work. In general, if your tailpipe is black, it means you're running rich. However, to find whether you are rich or lean at a certain rev zone, I was taught to do a throttle chop. You run the bike at various RPMs and hit the kill switch, then pull a plug to see what color the plugs are. If they're black and gooey, you're way rich. A perfectly jetted bike will be gray, and a lean bike will be tan. Oh, and if your bike backfires when you are decellerating, you are also probably rich.

- Getting more fuel by the needle (richening the mixture). You LIFT the needle up, which means LOWERING the clip on the needle, towards the point. The farther out of the hole the needle is, the more fuel that will flow by it. This will affect low throttle applications, under 5000 rpms or so (I'm not really sure of the range, this is an approximation).

- Getting more fuel from the mixture screw (richening the mixture). First, find out there your screws are currently set, by screwing one entirely in, counting the turns on your screwdriver. Then, to richen your mixture, turn the screw out more! I move it out by 1/2 turns, and currently have my 7-11 with 36s turned out 2 1/2 turns (but I am at 8,000 feet in altitude, so this probably won't apply to your application). Oh, and this effects the mixture just off of idle.

Hope I have helped. If you need more assistance I'll need to go to the garage, where I've got a lot more info.
 
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