471 stroker hitting rev limiter way fast - Page 2 - Yamaha YFZ450 Forum : YFZ450, YFZ450R, YFZ450X Forums

**Terse** · 11-30-2011, 09:06 AM

If you leve the needle on the 4th clip, the 175 my be just right... yes with your mods t your elevation. Higher elevation = need less fuel, because there is less Oxygen. The only mod I don't see is a bigger carb.... and all your current mods dictate leaner jetting.

The Q needle is a rich needle especially in the mid range.... if it were me I'd try to drop the main again (it's easier) re test..... if no change then I would go to clip #3 and try a richer main. Rich mid range (needles) use leaner main jets... and leaner mid range use richer main jets.... from what I have seen.

WickdYFZ450R · 12-02-2011, 11:17 AM

When you have the jetting dead on it will run like a rape ape.

silverado2nv · 01-25-2012, 12:18 AM

Well still haven't made it to waynoka... But looks like I will on the 4th even if it is just for a tune and no sand time...I'll post results... Quad is still rich and not running 100%

yfzxsocal · 01-25-2012, 01:06 AM

Did you ever try a leaner main jet??....everything that everyone is saying about being rich is true. I had the same issue your having about reaching the "rev limiter" too soon but it was due to rich jetting. I leaned out my main jet, fuel screw and moved the needle down from the 3rd clip to the 4th and it made a HUGE difference. Cornered way better and revved longer.

silverado2nv · 01-26-2012, 01:57 AM

I moved the needle down one and it got better... I know I'm still rich some but I'm just going to wait and let the pros fine tune it...well see on the 4th

silverado2nv · 02-04-2012, 09:50 PM

Well got on the dyno today!!! Base numbers were real low like 43 ish and went to a stronger 48... With a needle move and some way leaner jets... We left it a little richer but it was real cold like 35 degrees and last time i rode at waynoka it was real hot so we wanted to be safer... It gained 2 hp every time mike jetted down.. I ended up with 3 clip and a 165 main... He said if its still to rich in the summer that a 160 would fix it... I bet I could have broke into the 50 hp mark if we went leaner but the numbers don't mean shit to me all I wanted was a good reliable tune... And mike at waynoka got it done!!super nice guy with a ton of knowledge... If y'all go to waynoka get a dyno tune... Cheapest hp I've ever gotten!

**Terse** · 02-04-2012, 10:15 PM

Yeah Mike is super cool and knows his tuning! Glad you got her all figured out!

Redbull · 02-06-2012, 04:15 PM

just get a bigger front sprocket and a smaller rear sprocket (optional) its a huge difference and feel regarding to speed and when hitting the rev limiter

12-02-2011, 11:17 AM	#22 (permalink)
WickdYFZ450R Senior Member Join Date: Aug 2011 Location: Fredericksburg,Va Posts: 613	When you have the jetting dead on it will run like a rape ape. __________________ Sponsored by: Immortal ATV 2011 YFZ450R Few Mods

01-25-2012, 12:18 AM	#23 (permalink)
silverado2nv Senior Member Join Date: Jan 2011 Posts: 125	Well still haven't made it to waynoka... But looks like I will on the 4th even if it is just for a tune and no sand time...I'll post results... Quad is still rich and not running 100% __________________

01-25-2012, 01:06 AM	#24 (permalink)
yfzxsocal Senior Member Join Date: May 2010 Location: SoCaL Posts: 142	Did you ever try a leaner main jet??....everything that everyone is saying about being rich is true. I had the same issue your having about reaching the "rev limiter" too soon but it was due to rich jetting. I leaned out my main jet, fuel screw and moved the needle down from the 3rd clip to the 4th and it made a HUGE difference. Cornered way better and revved longer. __________________ 06 YFZ 450 SE Laeger +2 A Arms Fox Evol Floats Fox Podium w/ Houser linkage Lonestar +2 Steering stem Pro Taper Contour HandleBars Alba Pipe FCI Pro Elite Nerf Bars Pro Elite Bumper Cam Mod Zip Tie Mod 07 OIL UPGRADE

01-26-2012, 01:57 AM	#25 (permalink)
silverado2nv Senior Member Join Date: Jan 2011 Posts: 125	I moved the needle down one and it got better... I know I'm still rich some but I'm just going to wait and let the pros fine tune it...well see on the 4th __________________

02-04-2012, 09:50 PM	#26 (permalink)
silverado2nv Senior Member Join Date: Jan 2011 Posts: 125	Well got on the dyno today!!! Base numbers were real low like 43 ish and went to a stronger 48... With a needle move and some way leaner jets... We left it a little richer but it was real cold like 35 degrees and last time i rode at waynoka it was real hot so we wanted to be safer... It gained 2 hp every time mike jetted down.. I ended up with 3 clip and a 165 main... He said if its still to rich in the summer that a 160 would fix it... I bet I could have broke into the 50 hp mark if we went leaner but the numbers don't mean shit to me all I wanted was a good reliable tune... And mike at waynoka got it done!!super nice guy with a ton of knowledge... If y'all go to waynoka get a dyno tune... Cheapest hp I've ever gotten! __________________

11-30-2011, 09:06 AM	#21 (permalink)
Terse Bad Azz Admin Join Date: Aug 2005 Location: Colorado Springs, CO Posts: 10,127	If you leve the needle on the 4th clip, the 175 my be just right... yes with your mods t your elevation. Higher elevation = need less fuel, because there is less Oxygen. The only mod I don't see is a bigger carb.... and all your current mods dictate leaner jetting. The Q needle is a rich needle especially in the mid range.... if it were me I'd try to drop the main again (it's easier) re test..... if no change then I would go to clip #3 and try a richer main. Rich mid range (needles) use leaner main jets... and leaner mid range use richer main jets.... from what I have seen.

02-04-2012, 10:15 PM	#27 (permalink)
Terse Bad Azz Admin Join Date: Aug 2005 Location: Colorado Springs, CO Posts: 10,127	Yeah Mike is super cool and knows his tuning! Glad you got her all figured out!

02-06-2012, 04:15 PM	#28 (permalink)
Redbull Member Join Date: Dec 2011 Location: Pennsylvania Posts: 60	just get a bigger front sprocket and a smaller rear sprocket (optional) its a huge difference and feel regarding to speed and when hitting the rev limiter

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