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Discussion Starter #1
I have to press the starter button 5-10 times while opening the throttle halfway to get it to start. Choke doesn't help, i need to twist the throttle to get it to start. For the first 5 minutes it wants to stall at idle, but accellerates and runs fine. Once it gets warmed up, it doesnt stall at idle anymore but the idle is too fast.

I tried adjusting the throttle stop screw (?), the screw on the left side on the bottom of the carburetor. If I try to turn it down to a normal idle speed, it stalls even when warm.

If I open and close the throttle very quickly that stalls it sometimes too.

I just cleaned all the jets in the carburetor but no change.

Jets are stock, exhaust stock.

Thank you for reading.
 

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Turn the pilot screw out 1 full turn and try starting again. If this has good results (and I bet it will) , proceed to warm the bike up to operating temp and adjust the pilot mixture. Once warm, turn the idle down to 800-1000 rpms. Slowly turn the pilot screw out (or in) until the idle reaches its highest level. Back the throttle stop screw out until the idle is at an acceptable speed and you should be good to go. Good luck!
 

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Well, I can't say for sure without hearing the engine, but in my experience with these little thumpers an erratic idle is usually attributable to pilot mixture. I finally put a thumb knob on my pilot screw because I got tired of adjusting it with a screwdriver every week and burning myself. My bike will idle differently and act up if the ambient temp fluctuates even 10 degrees. The relative humidity affects it too.
 

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Thanks I want to try this but I'm kind of confused about the whole process.
Please correct me if I have got this wrong.
1. Turn out the pilot screw an extra turn to richen the idle. (?)
2. Start the bike and see if it starts easier.
3. Run the engine a few minutes until warm.
4. Turn out the pilot screw more with the engine running until the idle is at its highest.
5. Turn the throttle stop down until the idle is comfortable.
Yep. That's pretty much it. You have the CV carb I believe, and I can't remember the base setting off-hand. Maybe 2.5 turns from seated? There is a bit of trial and error involved with this.

1. Slowly turn the pilot screw in until seated. Count the turns so you have a baseline to reference. Write it down.
2. Turn the pilot screw back out to the baseline +1 turn.
3. Try starting the engine. Any better? If not try turning out an additional turn.
4. Try starting.
The goal initially will be to get the engine started and idling. Once its idling and warm, slowly turn the pilot in or out and listen to the idle speed. Find the pilot screw position where the idle is highest and leave it there. That will be your correct pilot mixture. Now turn the idle stop screw out until your idle speed sounds right.

This is an exercise in carburetor tuning by ear and it takes a bit of practice and patience, but well worth it in the end.
 

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There is a extended pilot screw available on this forum. Can't remember who sells it. Keep me posted on your carb adjustment. I hope it works for you...good luck!
 
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