Maintenance & Technical > KX500 Original

What does pinging sound like?

(1/2) > >>

dnmac1999:
  Hey guys i finally got the 500 running. I was out rideing and adjusting the carb, was way to rich. It didnt make the noise when it was rich but as i leaned it up it started makeing this weird noise. I have never heard this before on any of my bikes. It sounds like im hiting the pipe with a hammer. It only does it if i just barelly let off the throttle. Is this pinging? How could I fix this?

stroke.n.smoke:
You could try backing the timing off or run race fuel.  I bought some VP C111 and mine doesn't ping a bit since.

Platypus:
Probably a good idea to know what spark plug you are running as well.

maddoggy:
dnmac, the condition you are describing is called pre-det. or predetonation. it happens to the big bore high compression 2 strokes when you don't use fuel that has a high enough octane rating. the lower octane fuel ignites at alot less compression which is known as spontaneous compression combustion. basically the fuel is detonated before the piston is in the right location on the up stroke which puts major downforce on it as it is still on it's way up putting tremendous stress on the piston, head, gaskets, bearings etc...  when you lean up the mixture in the carb. ,it will get even worse. if the pre det. or pinging is allowed to continue, you will probably be rebuilding your engine soon wether you want to or not. these bikes are built to perform and the big performance costs big money. pay for some quality high octane race fuel in your bike and the problem will surely go away. or you can run lower octane and you'll end up paying big money anyways to repair the damage done to your engine. trust me i've seen it. hope the info helps, MADDOGGY

dnmac1999:
  Wow thats exactly what I was hopeing not to hear. I just got it running, and never ran it before. I dont know anything about the head if it was milled or not. Sounds lke it was to me. Ill look for a stock head i guess, and run race fuel untill then. Can I get away with Half and half?

Navigation

[0] Message Index

[#] Next page