Happy new year to all bull riders out there!
Despite different combinations of pilot jet/main jet/needle positions(UCAL BS29 carb), my bike seems to pop horrendously. Right now the main jet s 120, pilot is 15 and needle raised one notch.
Air screw is about 4 turns out - the bike doesnt pull well at all.
Its a goldstar exhaust and a DU100 K&N air filter in the stock air box.
No air leaks in the intake or exhaust routes.
I had tried a 17.5 pilot before this but then the plug goes sooty.
Another question is: During tuning the air screw, I try to open up the air screw to get to the point where the RPM reaches the peak and then drops, this point never seem to show up at all!
Any ideas why this is so?
Perplexed, annoyed and fingers crossed
Thanks guys!
Sudhir
I've done a lot of playing around with this carb on my '08 Classic (bought with zero miles from an out of business dealer). I put 300 miles on it & went to an open exhaust & a K&N.
First off, that's not an air screw. It regulates fuel; Clockwise to lean.
After much back & forth (I probably had the carb off & on a dozen times dialing it in) I'm back to the stock 15 Pilot & the stock 110 Main with the needle lifted two shims. My needle has the permanent plastic collar on it over the notches so I can't talk notches with you. My mixture screw is about 1 1/2 turns out.
The bike runs perfectly set up this way & now has 600 miles. It kick starts under all conditions with one or two kicks (I never use the ES) & never dies at stop signs or pops or sputters or any other bad stuff. It pulls well in the first 4 gears up to my break-in speeds. I've only even been in 5th a couple times on flat stretches.
Once I can wind it up after more miles, I may find I need to go to the next bigger main, but right now 45 in 4th is smooth as silk & it pulls very quickly to 55 for very short periods.
It's a smooth running little bastard & I have none of the problems I hear here. Hear, hear!
Good luck with yours.
PS: Did your needle have the plastic collar on it when you first took the carb apart?
I wish now I had broken it off Day One & dialed it in using the notches.
Geo