Took the new to me '02 raptor 660 to 5000 feet elevation and noticed it had a popping sound, which I assumed was a lean condition, but also noticed it popped at low rpm's but cleared out at higher rpm's.

Got going up an old riverbed with a lot of football sized rocks and ended up stalling it out. It ran ok as long as you kept it above idle, at idle it died. Got it on level ground and noticed gas coming out of the vent tube that dumps on the swing arm pivot area. Also noticed the connection from the headpipe to the rest of the exhaust had carbon looking splatters like a rich 2 stroke will do, and the exhaust was sooted.

Got the bike home to 500' elevation and it runs great???? no carb overflow issues.

It has an aftermarket full exhaust, and had been jetted for 3000 elevation according to last owner.

So did a float stick open, and unstick back home, or is this a rich jetting condition, or both?

Thanks

 

Rappy's very sensitive to air/fuel mixture. At 5000 feet, the air is thinner and you will be running richer. Most will suggest you change your jets for this altitude. You may try just turning in your Pilot screws a 1/4 to a half turn. This will lean out the 1st 1/4 of the throttle travel and may fix the idle problems, but won't do a whole lot for the mixture beyond 1/4 throttle.

For a test, remove your airbox lid when you think you are running too rich. This will lean it out some over the whole throttle travel.

You also may want to try to adjust your float bowls using the 'clear tube' method described at bluetraxx.com and at raptorforum. com - everybody swears by it. May reduce your overflow issues, may not.

Good Luck!

 

Thank you

I will look into the float setting and try leaning the adjustment next trip, and probably should open it up and be prepared to rejet.....

I did try removing the lid, but it didn't clear up but maybe I didn't give it enough run time to do any good. Put the lid back on, walked it through the rocks ( luckily it was steep enough to ride it down with the clutch in) and once back on dirt I could keep it revved enough to ride the quad back to the trailer.

Allen

 

Are you flowing any fuel out of the overflow tubes down by the swing axle? Sounds like you're flooding when you bounce or go uphill? The clear tube method should get your floats at the optimum setting.

After that, see if it still seems rich.

 

Yes
"Got it on level ground and noticed gas coming out of the vent tube that dumps on the swing arm pivot area."

When we got it home and turned on the petcock it didn't flow out in about 1 minute, but I should run it at home and look for fuel flowing out of that tube again .

Sounds like a float issue..... hope that is all.

Thanks
Allen

 

Having trouble already at 5,000'...that's nothing. My typical mountain rides start at 4,000' and end at over 11,000'...all in one afternoon's ride.

I install several Thunder Products TPI valves in the airbox lid. As I ascend I open them up, and then when I descend, I close them back down. Above 9,000' I take the lid off altogether.

http://www.thunderproducts.com/tpi_valve.htm


This is a system that works surprisingly well, and it is very inexpensive! By increading the air intake, you are doing a "rejet" of sorts.

 

<div class="FTQUOTE"><begin quote>Originally posted by: reconranger

Having trouble already at 5,000'...that's nothing. My typical mountain rides start at 4,000' and end at over 11,000'...all in one afternoon's ride.

I install several Thunder Products TPI valves in the airbox lid. As I ascend I open them up, and then when I descend, I close them back down. Above 9,000' I take the lid off altogether.

<a target=_blank class=ftalternatingbarlinklarge href="http://www.thunderproducts.com/tpi_valve.htm
">http://www.thunderproducts.com/tpi_valve.htm
</a>

This is a system that works surprisingly well, and it is very inexpensive! By increading the air intake, you are doing a "rejet" of sorts.</end quote></div>

Every once in a while I am shocked by something's combination of brilliance yet simplicity. The TPI valve definitely qualifies! What a great idea.

 

If you adjust your floats and this does not work make sure your float needle and seat are free of dirt and if they still leak replace the float needle and the seat for that carb that is pretty much all it could be as far as fuel leaking from your carb.

 

I can't locate the clear tube adjustment method on Bluetraxx.

Any way to link to it, please?

Thanks
Allen