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Eldebrock Tuning Help

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Hey guys, I've been lurking here awhile, and have found the info incredibly usefull! Thanks to all! I finally came up with a question that I couldn't just search the arcives for an answer to...so here goes:

I recently installed an engine in my XR400 that was rebuilt with an HRC power-up kit. I'm stoked about the power increase, but have a question about tuning it. The previous owner replaced the stock carburator with the eldebrock (sp) unit, and tuned it for the stock engine. I'm running a Gordened, stock, exaust system. Does anyone have any experiance with a baseline setting for this motor/carb combo? I've done some tuning on street bikes, but have pretty much zero experiance with the eldebrock carb. I'm a member of the slow and careful break-in camp, so I haven't run it hard at all, but I'd hate to destroy a great motor through my inexperiance.

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search the XR650 site for tons of info about tuning this carb.

its very easy to do....very easy.

There are two adjustments--the pumper and the needle.

Pumper is the little screw on the side. With the bike warmed up, loosen the nut and take a screw driver to the screw. Wack the throttle. Adjust the screw until you have a perfect 'off-idle response' -- that means ZERO hesitation.

once thats done, turn off the motor. hold the throttle wide open. with the throttle open adjust the red knob (push down) on the top of the carb. rich is right, lean is left.

you want to adjust the red knowb until the bike pops once in awhile on super hard - rapid- deacceleration. So ride it hard, then wack off the throttle, and try to get it to pop. if its not popping yet--its still to rich. so go lean a bit more. if it pops a lot then you are to lean--so go a click richer and test it again....

for the XR650 i can tell you where to set it--but i dont know on the 400 (even though i have one on my 400!) ... the whole thing should take 20 minutes or so to do....and once its dialed--watch out-- the thing will hit better, get better milage, and never go out of tune-no matter what elevation or temperature! Its an awesome carb....best by far!

send me a pm if it still gives you problems or call Rob Barnum at barnumspro.com he is a nice guy who can talk you thru it, he is also a edelbrock distributer....

:cry:

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