Guys, I have the Sparks full exhaust and am jetted to 190 with open airbox. The jetting looked right and there is just the slightest amount of black smoke when revving in the main jet area. But the black smoke is only for a second and for very light, kinda like it might be just a tad bit to rich. The temperature is around 50 Fahrenheit and I am at 1600 feet altitude when I ride in the sand. Otherwise, I am at 800 feet where I ride the trails.

Anyways, I need to doublecheck the jet settings for my sanity, but here is my question/issue.

The sparks exhaust is glowing red leaving the motor. Sometimes it glows like this up to or past the bend. This mostly occurs when idling, however slow speeds can have a very similar effect. Everyone that saw how hot the pipe was, asked if I had it jetted to lean. I told them I didn't think so but would doublecheck. The 450R has never gotten hot or lost a drop of coolant. So what am I doing wrong? Or is this normal for the sparks exhaust?

The jets for the 450R keihin jump from 185 on up in increments of 5.

Please let me know what you think.

 

There are 3 circuits in the carb, pilot ,mid, and main. Sounds like the pilot circuit may be too lean, try adjusting the mixture screw out.
jetting Heres a link, on how to do that.

 

the stock exhaust will also do the same. when you go to a after market full exhaust it usually glows more because the aftermarket pipes are thiner and lighter.i have a 450r but i havent had a chance to get a pipe and jet kit yet. i also own a z400 and put a pro circuit full system, k&n pro flow kit and jet kit had the same problem.you might also try and call sparks just to be sure. i have seen the stock pipes on predators,z400,raptors,and even on the z250 do this.i have been told that four strokes build alot of heat.

 

black smoke is a sign of being rich.... but glowing red pipe is a sign of being lean. hmmm wierd[img]i/expressions/face-icon-small-confused.gif[/img]

 

Well, It took me a couple of days to get to, but I checked the plug and it looked fine. So I called Sparks and explained my issue, they asked what needles and jetting that I had. They said it sounded like the pilot jet was adjusted correctly. They said it should be four turns out. Well I checked it and it was only two turns out. So I screwed it in all the way and backed it out 4 full turns and let it idle for about 5 minutes and THE PIPE DIDN'T GLOW .... [img]i/expressions/face-icon-small-happy.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img]

Anyways, the pilot was working fine for the HRC-or at least I didn't notice the issue. But it has to be adjusted for the sparks pipe.

Thanks for the help.

 

mine does it too only when at idle but when riding (air cooled) it's fine i posted this question also and got replys they say is normal

 

After seeing the difference and talking with Sparks I would have to say that I disagree. Sparks said it was a lean condition in idle and I made the suggested setting and it worked. Luckily, I didn't let the 450R idle more than I had to last weekend.

[img]i/expressions/face-icon-small-happy.gif[/img]

 

Learningtofly, if youre 4 full turns out on the mixture screw, you should go one up on the pilot jet. That would let the screw be about 1 1/2 turns out. Usually, anything over three turns, means go up one.

 

Yeah, you're probably right. Sparks did say that if this didn't fix the problem, that I should go up one on the pilot jet. Is there any issue with running this way (other than losing some adjustment control)?

 

Actually youll gain more control over the adjustment by going up one. At 4 turns out, the pilot circuit is at the full flow limit. By jetting up, youll end up with about 2 turns out, and have room to move either in or out.
tuning