sst pipe on a 04 rm 125?

[250racing]

so i got the pipe from e-bay and i did it before researching this site. after i researched i saw that it wasnt a good buy because of detonation.

i usually ride my stock bike only fitted with a powernow and boyesen pro series reeds at 4500' plus altitudes could the altitude play in my favor and reduce detonation? i know that at this altitude the motor has less compression and horsepower. could i retard the the timing to fight detonation?

how can i identify detonation as i have never identified that condition.

thanks all the help is appreciated.

Andres macias.

 

[Chili]

On my son's 03 RM we saw very minor detonation with the SST that we covered by some simple octane booster (Torco Mach Accelerator). I can't be certain but I think the altitude may play to your advantage here. As far as recognizing detonation if it is bad you'll get the obvious pinging, for us it was noticed at the first ring replacement when there was some very minor pitting around the outside of the piston crown.

 

[250racing]

thanks chili,

torco is not available in my area. do you think maximas octane booster is a good option?

i could mix race gas with pump gas could that work too? vp red?

 

[Chili]

A mix of race fuel with the pump will work fine, I was just too cheap for the amount of fuel the kid burned through at that time. If it was now I'd probably push the bike right to the edge of tuning and run straight race fuel since he has a lot less time to ride.

 

[MXSparx]

VP C-12
Red works best with engines with a longer intake track.

 

[CRrider125r]

What is detonation?

What do you mean this pipe will cause this?
Because i bought an 01 cr125 with this pipe on it .

 

[CHR!S]

What is detonation?

What do you mean this pipe will cause this?
Because i bought an 01 cr125 with this pipe on it .

detonation is when the fuel air mixture ignites in the cylinder before the spark plug sparks. the fuel ignites because of the pressure in the cylinder is too high for the octane rating of your gas. the opposing flame fronts (from the spark plug and the detonation) collide and put stress on your engine. what is meant by the pipe causing this condition is that the pipe is more constrictive and puts backpressure on the engine. that pipe may not cause pinging with you're particular bike, modifications, and atmospheric conditions, though.

about the altitude, your going to run richer because the air is thinner.

i know that at this altitude the motor has less compression

compression is the cause of detonation so i would say the altitude is on your side. i have a yz250 w/ and sst pipe and so far it runs good (i do not use race gas, just premium @ the pump).

here is more on octane rating and some on detonation
http://auto.howstuffworks.com/question90.htm the article says four stroke, but the principles still apply.

 

[250racing]

thanks i will try the bike with the pipe and a little octane booster from maxima mixed with fresh 93 octane pump gas if theres a problem i will mix some race gas and some pump gas.

hopefully the 4500' feet that robs plenty of hp on my bike help in this case.

 

[Chili]

Have you dialed in your jetting previously? Not sure on the 04 but or 03 was ridicuously rich and his current 05 was at least a couple rich on the main and one on the pilot for us at 700' feet. If you still have the stock jetting in there odds are you'll have no issue with detonation as it will be too rich already.

 

[250racing]

Have you dialed in your jetting previously? Not sure on the 04 but or 03 was ridicuously rich and his current 05 was at least a couple rich on the main and one on the pilot for us at 700' feet. If you still have the stock jetting in there odds are you'll have no issue with detonation as it will be too rich already.

i did jet my bike. in fact i jetted it so spot on that some faulty gas at a remote town made a bellybutto in my piston. now i just get good quality gas at busy stations.