I have an annoying problem with my bastard exciter 570.... I put on the original carbs together with the airbox) the jetting is according to the psi sheets, 330 mains, 47,5 pilots and airscrew has been between 0,5 to 1,5 turns out without much difference. Sled runs fine in low and mid but when u hit full throttle it just hesitates sometimes misfires and slows down. Just Sounds like böööööhhhh. When u let go of the throttle it runs better again... Is it lean in main even though the jetting is according to specs? It is bored 0.40 and ported aswell. I had flatslides with pods before and did not have this problem, help in this matter would be very appreciated thanx
Throttle Junkie35
New member
That does sound like a lean issue. What cylinders are you running?? Are running the earlier cylinders or the later 88r's?? Have you checked the compression lately?? What are you running for needles and nozzles?? It could be a coincidence, but maybe your crank seals are starting to go. What temps are you running in?? My psi spec sheet I have calls for a 42.5 pilot. 330 mains is what they call for stock porting. You may have to increase the main. I would go to a 340/350 mj. Thats what I run in my set up with ported cylinders. Im running an RPC single and my plugs looked perfect at 0 to 15+f degrees. It was slightly rich above 20f degrees
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I have no idea which cylinders i got on it, how can i tell the difference? I think it may be lean on high rpm as u say. Will try 340/350 mains and see if it gets better thanx
Throttle Junkie35
New member
There is a number that is cast on the cylinders. Should be visible on the mag cylinder on the upper right hand corner if your standing and looking at the sled on the same side. Should either be 84M, 86M, 88R, or 8AY (SX) I found out this year that the 91-93 exciters require slightly different jetting than the older exciters. I had my 88 and my friends 92 set up identical with same pipe and piston cut. My 88 does have a mild port job and it shows because of the richer mains needed, but the weird part is that I ended up leaner on the pilot. The richer needle and needle jet makes sense since the 91-93 exciters have a redesigned, longer intake track to eliminate a lean mid range burn down problem like the older exciters experienced. Heres the differences I had. The 88 had a 42.5 pilot, 6dh4, Q-6, 340/350. The 92 ran best with 45 pilot, 6fl82, P-6, 330. So I take it for what its worth. You may have to go outside the box of jetting spec to make your set up work.
It was the ****in plungers that were the big issue, to little slack.... Took me a day to find out lol. Took the carbs apart and tried different mains, cleaned etc. Appreciate your answers throttle! If the fullthrottle bog continues after this i look for other nozzles. I had the p6 in now with fl82 needles. Tried the 330 main now but will go to
340 after this. Hoppfully it works better otherwise i steal back the flatslides from the other one
340 after this. Hoppfully it works better otherwise i steal back the flatslides from the other one