Jets

Now that the weather is a little nicer, I’ve taken the time to start tuning this thing. Plus, the new owner will be picking it up in two weeks and I would like it to be running great by then.

This is more of a reminder for myself, but I thought I would share it as well. The 21mm Dellorto PHBG has these settings right now:
50 idle jet
60 choke jet
84 main jet
W3 needle with the clip at the top

The bike does not run well. It 4 strokes through the entire throttle range. It almost left me stranded yesterday. I pulled up to a stop sign a couple miles from my house and it died. I got it started, but it would not run. I ended up pulling the air filter off and that allowed it to run enough to get me home. I’m thinking it is rich all over. I ordered a new 38 idle jet from treatland.tv and I think I’ll put a 80 main jet at the same time. Although, my bike is very similar to this with just a slightly smaller carb (20mm) and an 82 main jet and it runs great, so I’m a little hesitant to drop the main jet much more.

3 Responses

  1. Responsible Jon Says:

    Main jet is fine, your idle jet is about 12 sizes too large. Once you get that set in, also lean out your a/f mixture screw. Lean = turned out

  2. admin Says:

    So, who is wrong…you, the wiki, or I just don’t get it?

    “Fourth: Do 1/8th revs rotating the mixture screw until it is fast and responsive. If it is studdering like its rich, turn it IN. If it is boggy or responsive, turn it out until it just starts to four stroke, then turn it in half to one full turn until it just stops four stroking. That is your safe/hot spot.”

  3. Responsible Jon Says:

    I’m wrong! Mis-spoke!

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