Is my bike pinging? Jetted lean stock?

[Casper250]

I was riding in the sand pits near me and I noticed sort of a pinging noise, more like a rattle after a while. The bike runs hot in the sand cause you are at WFO about 80% of the time but I have never really had a problem before. The bikes jetting is stock and it was about 45 degrees out. When I replace the plugs, they always looked good, so the jetting was pretty good stock. The bike is new and I couldn't find anything loose on it. I went over every bolt with my T-wrenches and nothing was loose so now I'm suspecting it might have been pinging that I heard.

Usually stock bikes come jetted more on the rich side then the lean side but is it possible that with the bike running in the sand and running hot that it started to ping?

 

[Bullwinkle58]

Yeah, it's possible. Mine does it in the summer on pump fuel, and the motor is stock. Try using a 50/50 mix of race fuel & pump fuel.

 

[NateZ]

Piston slap?

Nate

 

[Studboy]

Casper, I've heard of the YZ's pinging a little bit when stock and running pump fuel.

My YZ will ping at the sand dunes when run hard and running pump fuel, and I'm at 4000+ ft!

Mixing a little bit of race gas (C12) cures this. I've found that I only need the race gas at the sand dunes.

 

[Casper250]

Just to make sure, does the pinging sound like somethings loose or rattling? I've never really heard a bike ping but I know what it sounds like in a car.

 

[adrenaline420]

My 04 YZ 250 pings on pump gas, but now I use octane boost with my gas, and it cured the pinging. the YZ 250's are known for the pinging, just needs little race gas, and its perfect. 2 STOKE 4 LIFE.!!

 

[NateZ]

Is pinging somthing i will definatly notice when riding? (something way out of the ordinary?) I have a yz250, it's been gettin hotter down here, ride hard to moderate mabye? Sand like above. Happens under load or? I run 93 octane btw

Nate

 

[gonzo843]

My 250 pings too. Try the 50/50 mix or maybe some octane booster.

 

[yam 3]

My 04 YZ 250 pings on pump gas, but now I use octane boost with my gas, and it cured the pinging. the YZ 250's are known for the pinging, just needs little race gas, and its perfect. 2 STOKE 4 LIFE.!!

What kind of booster do you use, and how much per gallon?

 

[Studboy]

The problem with using the octane booster is that it kills your throttle response, and you really don't get much gain. You would be much better off experimenting with mixing a quality race fuel until you stopped the pinging.

 

[adrenaline420]

i just use NOS octane boost.I live in canada so I dont know how much gallons, but 1 bottle is good up to 60 litres of gas.

 

[SpectraSVT]

My 2003 does this also when its running lean. If race gas don't cure it then look into dropping the needle clip down.