XR 100 Pilot jet and pilot (air) screw question. How to adjust properly?

[schmitty]

2000 XR100

- Completely took my carb apart and forgot to check # of turns my pilot screw. How do I adjust properly?

- Is the pilot (slow) jet tapered on the inside (unlike the main jet which seems to have a constant I.D. bore from top to bottom). I was running some wire through either end of the pilot jet to clean out. Each time the wire did not want to go completely through. I could see some light through it and able to blow a bit a air through? Is it clogged or OK?

Any help would be appreciated, as I'm going to put back together.

[Stu35]

There is a ratio that you use. If you run a 45 PJ then you turn out your PAS one full turn from seated. One turn equals a 100 pilot air jet. The ratio is 45:100 Therefore, if you have a 40 pj then you should run a 89 pas or 7/8ths of a turn out from seated.

Stu

[Wayward Son]

where is the mix screw located on your carb.pretty sure its a fuel screw.

https://www.thumpertalk.com/forum/showthread.php?t=327405

[schmitty]

Thanks Stu........any chance you know the answer to this one

Is the pilot (slow) jet tapered on the inside (unlike the main jet which seems to have a constant I.D. bore from top to bottom). I was trying to run some wire through both ends of the pilot jet to clean out. Each time the wire did not want to go completely through. I could see some light through it and able to blow a bit a air through? Is it clogged or OK?

[schmitty]

the manual calls it a pilot screw, it's located on the undersise of the carb, between the "cheeks" of the float bowl cover. It's about an inch long and tapers to a very fine, almost pin like point.

Also - Is the pilot (slow) jet tapered on the inside (unlike the main jet which seems to have a constant I.D. bore from top to bottom). I was trying to run some wire through both ends of the pilot jet to clean out. Each time the wire did not want to go completely through. I could see some light through it and able to blow a bit a air through? Is it clogged or OK?

[Wayward Son]

the wire you were using wasnt small enough.be carefull as youwill change the size of the jet.

its a fuel screw.out is richer.

[schmitty]

the wire you were using wasnt small enough.be carefull as youwill change the size of the jet.

its a fuel screw.out is richer.

The I.D. of the pilot screw is (appears) to be unlike the main jet. The main jet I.D. is constant throughout, like looking into a straw. My pilot jet is either clogged or it tapers in the middle section. While I can slip a very thin wire (were talking a periodontal wire from my dentist) into the top and bottom about 1/4", I can't get it completely through.....although as I said before I can see light through it, and blow a bit a air through it.

Is the I.D. tapered or is it clogged?

[R_Little]

Xr100 pilot jets clog very easily. get a new one if the bike won't idle right.

Once the pilot is clean, turn the idle way down then adjust the fuel srew for max rpm then turn it back in about 1/2 turn.

Should start with your hand when hot and settle into a nice idle when it is adjusted correctly.

[Stu35]

If you are actually talking about the fuel screw, my first reply does not apply. I was talking about the PAS - pilot air screw.