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rc3
05-12-2004, 08:30 PM
I have a serious problem with the way my bike is running. The head pipe is glowing red, it is shooting flames out the muffler. And sounds funny when you gas it. Here is what I got done, cam timing mod, Full Yoshi Exhaust, Pro Flo kit with K&N Filter , with no air box lid. I am running a 45 pilot jet, 4th clip on GYTR Needle, and a 17o main. ANY AND ALL HELP WOULD BE GREATLY APPRECIATED!

beak7707
05-12-2004, 08:36 PM
I dont have a 450 and cant give any great info, but it sounds lean to me.

5valves
05-12-2004, 08:52 PM
Red head pipe is fairly normal, when bike is setting still.
You might be a little fat with the main jet. I run a 165.

rc3
05-12-2004, 09:06 PM
where are you located running that 165!

Kennethyfz450
05-13-2004, 05:00 AM
go to www.yfzcentral.com and get some better information ..

seatec
05-13-2004, 02:51 PM
hey is not fat but lean! go to a 175 and maybe even a 48 pilot.

rc3
05-13-2004, 08:47 PM
ok, I will try some bigger jetting tomorrow!

EvilJester400EX
05-13-2004, 08:58 PM
A 48 pilot jet should be alright. Try the 175 main, maybe bump it up one more size.

rc3
05-15-2004, 05:13 PM
Right now I switched it to a 55 pilot, 3 turns out on the air screw, 4th clip on GYTR needle, and a 185 main jet. I will have to see how that turns out on my first ride test. Is anyone on here running this rich!

tt racer
05-25-2004, 08:11 PM
The reason your pilot is so big is because your fuel screw is too lean. Turn it in to richen it. Maybe 2 turns out, youll just have to try.:eek2:

SRH
05-26-2004, 04:33 PM
mine shoots blue flames and glows red but no different than most other yfzs, its really dpends on the extent of it and the way it runs, mine runs pretty smooth no rough spots or hesitations

Maxx_Action
05-26-2004, 04:46 PM
Hey...

a 48 pilot is too rich unless you have done porting. Ask anyone who checks their plug they will tell you it will be caked with black carbon. The pipe glowing is pretty normal, but the main jetting can be higher than you think if you have a K&N or other mods to increase airflow. I listened to all these guys about running 168s and 170's being adequate, no way!. I got the woods intake and k&N and with a 180 main the plug is a perfect brownish grey color and screams like a scalded monkey. I wouldn't worry about the pipe glowing though, it's pretty normal.

Maxx

Bill Fuller
05-26-2004, 04:55 PM
I have stock air filter,airbox lid on and full HMF with quiet core.I am running 45 pilot,165 main with NQCV needle on the 4th clip and air/fuel mixture at 2 1/4 turns out.I have a slight hicup every once in a while while under hard exceleration no biggie probably a little fat on the needle.Don't worry about the pipe thats normal.

rc3
05-26-2004, 05:58 PM
I just went to a 45 pilot and 4th clip on the needle, and a 180 main, and it got hot, fan came on, pipe was brighter than before, I think I will have to stick with the 55 for now, I know it seems rich, but I will try it, better rich then lean, my local dealer told me I needed to run a with my air screw at 3.25 turns out! yes or no

Maxx_Action
05-26-2004, 08:25 PM
Originally posted by rc3
I just went to a 45 pilot and 4th clip on the needle, and a 180 main, and it got hot, fan came on, pipe was brighter than before, I think I will have to stick with the 55 for now, I know it seems rich, but I will try it, better rich then lean, my local dealer told me I needed to run a with my air screw at 3.25 turns out! yes or no

Dude...

I have been through about 50 different jetting combos. That thing will be gargling with a 55 pilot. The pipe glowing DOES NOT MEAN IT"S TOO LEAN!! Especially if you haven't done the cam mod. IT will be so lazy down low with that much pilot. You want it to snap down low when you need it coming out of a corner or through the whoops, it probably wont with that much pilot. Also, more than 1 and a half to two turns is silly IMHO, but to each their own....

Maxx

5valves
05-27-2004, 01:50 AM
Yep,
Your gonna loose your air screw that far out.
You are way to fat.
1-1/2 is where the air screw needs to be. adjust your pilot to suite that.

go back to a 45 or 48 and a 165-168 and try that

Bill Fuller
05-27-2004, 05:16 AM
Are you riding the bike between jetting changes?The high rev motor is almost impossible to jet while in the garage and on a stand.Jet it for performance(ridability/seat of the pants feel)instead of sound.Check YFZ.CENTRAL and look for DADOGS Jetting page.