KDXRIDER.NET

I got the RB carb and head mods, FMF Gnarly desert pipe and turbinecore2 silencer and Boyesen 607 reeds. The problem I am having is I can't get it to idle. There is a screw by the choke with a spring I thought was the idle screw. I turned it in 2 full turns but it didn't really make a noticeable difference so I put it back to where it was. Not sure what to do.

Keep turning the screw in.

Ok I will turn it in more tomorrow and see what happens. I know the carb is clean (no dirty jets) since it's actually a brand new RB carb.

Short story long :-). I just found something recently after installing a new 35 air striker. The pilot was too rich to begin with so I ended up screwing in the idle screw basically all the way in while messing around with it. After installing a 42 pilot I was going to get my idle lower to check for throttle response with the air screw. I was loosening the idle screw and then the idle started to raise. I kept unscrewing and it was raising more and then finally started to drop. I believe I was partially bypassing the pilot circuit by raising the slide too high. Long story short, my idle screw has a definite sweet spot and now a 1/4 turn in either direction will either kill the engine or make it idle too high. If I keep turning it in the idle then starts to drop and runs rougher. Keep the bike running with the throttle and loosen the idle screw more than you would think and see if starts to raise. I started another bike of mine with a 38 air striker and found the same thing. I had the idle screw in too far and as I loosened it, the idle dropped where I had to work the throttle to keep it going and then started to raise again while unscrewing it until I found the sweet spot. Now both bikes are idling cleaner than they ever have. I need to screw it in all the way tight and count the number of turns so I know for the future. It's a small window and even 1/8 turn either way is pretty drastic with the rpm's.

I really hope my pilot jet isn't too rich. I have heard others say a rich pilot will cause it not to idle? Going to mess with the screw tomorrow and hopefully that fixes it.

Make sure throttle cable adjustment is correct as well

Mine was a new 35 air striker that came with a 48 pilot AND the float height was off from the factory. I realized it when I put my bike on a triangle stand and it would leak from the overflow. So I was chasing an overly rich condition and had my idle screw all the way in to try and keep it running while tuning the air screw. Yours being an RB carb I would trust that your pilot jet is the correct size and just need to keep messing with the air and idle screw, engine fully warmed up.

I turned the screw in 3 turns and it really made a big difference over 2 turns. After that it really made a difference and got it idling good.