Motorcycle Repair: carb, honda xr100r, compression stroke

Question
i change out my jets,main,float,and clean the carb.is starst one crank but i cant find the right idle speed.i did the 1 and half turn but it runs high still so i just listen by ear,but i notice that it tends to go high then back down thats the idle.i dont need to gas it for it to go high for a few seconds then drops back down i have a honda xr 100r 02

Answer
Desmond.. the screw on the side is the idle speed screw. Normally, it is turned out until it isn't lifting the slide, then turn it in until it just raises the slide and then add about 1/4 turn. The screw underneath is the idle mixture screw and that is the one that needs about 1 1/2 turns to begin, then dial it in when the engine is fully warmed up.

http://www.cmsnl.com/honda-xr100r-00-us_model7726/partslist/E++16.html

The ignition timing is pre-set in the CDI module, so adjustments to make there.

Take time to adjust the valves to .002" COLD in/exhaust on compression stroke.

The ignition timing and carburetor adjustments go hand in hand.... if you crank up the idle speed too much the spark advance kicks in and the engine speed increases further.

Set the idle speed down low, fine-tune the idle mixture screw and it should be fine, unless you are having compression issues. Tight valves will cause poor idle and performance issues.

Bill Silver