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Old 12-23-2012, 03:13 PM   #434
ow, my balls!
crashmaster's Avatar
Joined: Mar 2007
Location: Alaska
Oddometer: 5,298
Basically the carb works like this......

The idle mixture screw controls the air/fuel in the pilot jet. Hopefully you have a screw with the adjustment knob on it so you dont need to use a screwdiver or twist the carb in the boots. It makes things way easier and much faster so if you dont have one , I would probably try to get one if it will work with your bike. Although getting a good one can be tricky, some of the cheaper ones like to break off the tip of the needle in the pilot jet if screw it in too tight. I've seen good aftermarket ones and I have also fabricated a quick adjustment knob using he stock screw. Colombia is a perfect place to have something like that done. Might want to find a couple extra screws just for piece of mind or you mess one up during the fabrication process.

With the bike fully hot up and idling, slowly turn the screw clockwise (in) until the bike starts to idle rough, then slowly back it out in small steps and the idle will speed up. When you find smoothest and fastest idle on your way out you are properly adjusted. Take the bike for a spin and see how it does.

You have a pilot jet and a main jet. Is this a Mikuni 41mm CV? You adjust the idle mixture screw as above, then actually change out the main jet to a different size when you need to. There is quite a bit of adjustment on the pilot circuit before you need to actually change the pilot jet. Usually you can turn the carb in the boots to make this an easy process. Not sure if you have enough room in the XRL to do this. I just havent worked on one in many years.

Up to about half throttle you are mostly on the pilot circuit and as you feed fuel the main jet comes into the system more and more. At WOT you are mostly on the main jet.

One thing to be careful about is running too lean. Run too lean and you burn up the top end so IMOH if you have to compromise a bit its always better to be slightly rich rather than slightly lean.
Riding the Americas: No Fumar Espaņol

crashmaster screwed with this post 12-23-2012 at 03:57 PM
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