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Home made leak jet for FCR39.

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I have a FCR39 fom CPW that I have been setting up as outlined in TT. Supposedly I want the accelerator pump to spray for 1 second when I stab the throttle. The way I got it from CPW it would spray for about 3 seconds. After reading about the taffy mod and the leak jets used on the modern WR/YZ FCR's, I examined mine. Fuel was fed to the accelerator pump from an orfice in the bottom of float bowl. This orfice was enlarged where it entered the accelerator pump and had a square brass plug inserted in it to act as a restriction. When the pump was actuated this restriction would prevent the majority of the fuel from being pumped back up into the float bowl and in turn force it up through another orfice into the carb throat. I took my smallest drill bit and drilled a hole in the center of the brass plug. My thinking was that this would allow more of the fuel to be pushed back into the float bowl and reduce my spray time. Now when you snap the throttle open the accelerator pump sprays for approx. 1 second. :) I figure I have now created my own leak jet.

I haven't actually ran the bike with this new carb in it yet but I was really proud of my self for coming up with this idea. God knows if it will really work.

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I'll have to take a look at this idea next time I have an FCR apart. Sounds good as long a you have modded a replaceable part. I hate to make non-reversible mods. I just put a slug in the bottom of the AP to limit travel. Works too.

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