Was it glowing why you were riding it or when it was idling? If it was when idling then kick the pilot up to a 48. Also I would adjust the needle to the 3rd or 4th notch from the top. Or get the ncvq needle that is what I run and I have a yoshi exhaust to. A lot of people use that needle. There only about 13 bucks at the dealer. Try that and see if that fixes it.
Jetting My 08' Yfz 450 Se
I just purchased an 08' yfz that the previous owner put a full yoshimura pipe on. He said that it still needed jetted. It wouldnt even barely start when i bought it. As of right now i jetted it to 45p. 170m. My stock needle didnt have a clip adjustments on it but my friends old stock one from his 04' did so we put that in with the clip on the 5th spot. I took it out and ran it for about 5-10 min and it seemed to run ok, but just as i feel im getting up there, it acts like im hitting the rev limiter. When i shut it off, It backfired a small flame out of the exhaust and the header was glowing red hot down to about an inch after the turn. Any ideas as to what i should adjust to straighten this out?
1 - 8 of 8 Posts
Nice first post. Search much?
http://yfz450.theatvchannel.com/invision/i...p?showtopic=908
I'm using the Q needle on the 3rd clip 168m 45p on a '07 motor with GYTR slip on. Runs pretty good as far as I can tell. Starts right up. Have to pull the choke half way on a sub 50F day for about 45 seconds.
http://yfz450.theatvchannel.com/invision/i...p?showtopic=908
I'm using the Q needle on the 3rd clip 168m 45p on a '07 motor with GYTR slip on. Runs pretty good as far as I can tell. Starts right up. Have to pull the choke half way on a sub 50F day for about 45 seconds.
Sounds like is running rich to me. Lid on or off? Lid off 168 max and lid on 162-165.
QUOTE (PIPO @ Mar 21 2009, 05:10 AM) index.php?act=findpost&pid=760317
If it's backfiring it cause it's lean not rich.Sounds like is running rich to me. Lid on or off? Lid off 168 max and lid on 162-165.[/b]
QUOTE
QUOTE (YFZRider69 @ Mar 21 2009, 06:42 PM) index.php?act=findpost&pid=760438When i shut it off, it backfired a small flame out of the exhaust[/b]
Two totally different things...like I said, sounds rich to me.If it's backfiring it cause it's lean not rich.[/b]
QUOTE (PIPO @ Mar 21 2009, 09:19 PM) index.php?act=findpost&pid=760529
How does that sound rich to you? You're jetting specs of 162-165 with lid on is way to small. Stock is 155. I have the same exhaust as he does with oversized k&n and i have my lid on with a 175. I just think the jets you recommended are to small.Two totally different things...like I said, sounds rich to me.[/b]
Flames coming out the pipe when shutting off the engine is due to unburn fuel. If backfires on decel then that's lean.
1 - 8 of 8 Posts
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