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01boneless
10-12-2011, 05:10 PM
ok so my 450 is doing great except after you rev it it stays at a high rev for a seconed or two then dies back down to idel . i though there was a air leak but I pushed the carb up onto all the books and tighned it up good and checked for cracks and did the carb cleaner test and notta ,now i dont think the carb is dirty cause its runnin good (other than a slight pop on decel) soooo any ideas?:huh
Baileygunns
10-12-2011, 05:40 PM
1. Make sure pilot jet and circuit is clean and clear
2. Turn the fuel screw out
3. Go up on pilot jet.
01boneless
10-12-2011, 06:13 PM
so you are suggestin it is lean? i mean i know it is a little cause the slight pop but i have never heard of it stayin reved a while when its lean its like a leak but i couldent find any thing im not sayin your wrong at all becuase i dont know lol :cool:
Baileygunns
10-12-2011, 06:37 PM
A leak would cause a lean condition also... But you said you checked for one and came up clean on that.

Holding a rev is usually caused from being lean. Not sure what you are running for jets but you should be some where around a 48-50 pilot (more then likely a 50) and an 185-190 main with that full pipe, filter and lid off.

I run a 50 and a 190, sparks pipe, K&N/ESR intake (no air box). I was running a 190 with just a K&N with air box and HRC lid.

Take a look at what you have in there for jets...
01boneless
10-12-2011, 06:49 PM
ok and how many turns out on the a/f befor ill need to bump the piliot?
Baileygunns
10-12-2011, 07:20 PM
I wouldn't go anymore then 3 turns out personally... Some do 3.5
01boneless
10-12-2011, 08:17 PM
ok so it has a 178(RD never heard of them) main jet and a 48 piliot (kehin) and the a/f was 2.25 out (i think lol) so i also found that im suprized it ran good as it did cause the carb was nasty !!! gunk corrosion thick too should help it alot when i clean it up .
so does 178 48 2.75 on the a/f screw sound good the screw was 2.25 so i figure since it was lean ill do 2.75 then if its rich ill go to 2.50?
quad71
10-13-2011, 01:12 AM
The hot start leans it out to may be sticking.
01boneless
10-13-2011, 07:12 AM
actully its stuck closed lol if any one knows how to loosen it up that would be good lol
Baileygunns
10-13-2011, 09:33 AM
I have no idea what that 178 actualy crosses to on a kehin jet... 48 pilot might be a bit lean. Start at 2.5 turns out and go from there. Make sure that carb is squeaky clean, that could have been your issue. And double check that hotstart, I know you were having issues with it. Check the cable, the plunger shouldn't be getting hung up inside the carb. If it is you really need to address that issue too.
ds268
10-13-2011, 10:13 AM
Check your intake valve clearances! I'd put money on saying that you have one of the valves is too tight with zero clearance that will need to be shimmed. The hanging idle is usually caused by a slight vacuum leak, causing the lean condition. Sounds like you have ruled out the carb jetting with what you've done. Intake valves should be .006" clearance.
01boneless
10-13-2011, 12:30 PM
ok guys i got it runnin good with the 178 main 48 piliot and a sqeeky clean carb ohh and i tried 2.75 turns and it was to lean so i did 3 even and it runs great no hesitation or popin thanks guys!!!!:D
Baileygunns
10-13-2011, 02:59 PM
Cool, glad you got a handle on it.
01boneless
10-13-2011, 04:08 PM
yup im still gonna pick up a 50 pliot though just becuase i dont feal safe with the a/f 3 turns out :p
Ruf Racing
10-13-2011, 04:12 PM
That's great! Your now, a certified 450R master mechanic. :D
Good idea on the pilot. You get out passed 3 turns, you risk the possibly of losing the screw.
01boneless
10-13-2011, 04:17 PM
^^^haha not evn close but i must say i do like these kickers becuase not much wireing :D
and ya deffinitly dont wana loose that screw lol so if it do a 50 how many turns shoul i go between 2.25 and 2.50 ?
Ruf Racing
10-13-2011, 05:10 PM
With the bigger pilot, you'll have to ride and see. But your guess is probably close. 2.0-2.5 Good luck!
01boneless
10-13-2011, 05:25 PM
ok im gunna try it then i hate takin every thing off just to turn thatlittle screw :mad:
Baileygunns
10-13-2011, 07:10 PM
Hey Fred... Did you see who's not a Mod on the ORG anymore? lol

and Boneless... I posted on your other thread.
01boneless
10-13-2011, 07:35 PM
nice !!!
Ruf Racing
10-14-2011, 01:03 PM
Originally posted by Baileygunns
Hey Fred... Did you see who's not a Mod on the ORG anymore? lol


Don't tease me Ed! No more Clown? It's a glorious day! :D