what is wrong

Freshly assembled motor. Running the hot cam with auto decompresion.

THUMPER1.jpg

100% SURE THE TIMING IS CORRECT

100% SURE THE VALVES ARE IN SPEC

EMP 3 CLIP

165 main

200 main air

40 pilot

75 pilot air

zip ty fuel screw

damn thing is very hard to start. I had this dream that once I rebuilt the motor all would be great. Pulled the pilot and fuel screw out, and shot brake cleaner through the pilot hole. Brake cleaner came out of the fuel screw hole and inside the carb throat. So the pilot ciruit is clear. What do I look at next? I humble enough to admit I could have done something wrong.

What elevation are you at? A 40 PJ seems pretty small. Try a 42-45 and it may help. Since doing the cam swap my bike is a bit harder to start and it seems that when I give it some gas it starts up no problem.

kind of like starting a 2 stroke. I am running a 42 but, I may need to go to a 45.

I sit between 0 to 1000 ' in elevation. I'll try a bigger pilot and let you know.

42 pilot seems to help. I will go to the bike shop Monday and get a 45. Hopefully I can get the bike to idle so I can run the fuel screw in, and out and prove the pilort circuit is in the ball park.

The starting drill for both my son's two-fiddy and my 444 with hot cams is: blip the throttle twice, kick the kicker thru slowly twice, one swift kick (with no throttle) and BBBRRRAAAAAAPPPPP.

Did you set the lash?

The starting drill for both my son's two-fiddy and my 444 with hot cams is: blip the throttle twice, kick the kicker thru slowly twice, one swift kick (with no throttle) and BBBRRRAAAAAAPPPPP.

What size PJ are you running Birdy? How many turns out on the fuel screw?

Man what a difference having the pilot circuit adjusted correctly makes. I'm running a 45 pilot and the bike starts easy, runs strong. Now if I could just feel good about the loud clatter in the head, when the bike is running. I read in the newbie threads that the bike will make uneasy sounds, but this seams out of character. Long story short, three years ago the bike was parked because I let the chain stretch and grenaded the motor. I have it all back together now and I don't remember it being this clattery.

What size PJ are you running Birdy? How many turns out on the fuel screw?

Max- As near as I can remember, I'm running a 42 pilot (it's been a long time since I diddled with the carb..but it's whatever JD recommends with his kit) and the fuel screw varies between 1-1/4 and 2 turns out depending on temperature.

Man what a difference having the pilot circuit adjusted correctly makes. I'm running a 45 pilot and the bike starts easy, runs strong. Now if I could just feel good about the loud clatter in the head, when the bike is running. I read in the newbie threads that the bike will make uneasy sounds, but this seams out of character. Long story short, three years ago the bike was parked because I let the chain stretch and grenaded the motor. I have it all back together now and I don't remember it being this clattery.

Are you sure the clatter is coming from the head? My 426 is pretty "clattery" too, but the noise is coming from the primary drive grears. Use a mechanic's stethescope or listen thru a long screwdriver...with a skid plate on, the noise sounds like it's coming from the head, but in reality it's bouncing off the skid plate.

If the noise is coming from the head, recheck your valve clearances, as they are probably too loose.

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