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2004 rm 250 losing a TON of torque suddenly.

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Ok guys I could use some help and I'm at the end of patience here. I have lost a ton of torque on my 2004 rm 250 after about 8 miles or so of singletrack riding today. I started out the day fine and thanks to some new reed valves had plenty of meat down low. I was pulling hard before I ever got close to the powerband. I was even popping up the front end completely out of the power band just based on smooth throttle and suspension input. Later on in the day after the engine got hot because of slow moving through the trails tighter sections the engine sounded pingy and I couldn't get any low end torque and it took forever to climb in the power band. I'm talking SLOOOOW pull from down low even in second gear. Full open throttle and like a half a second or so of no grunt before I hit the powerband. I had to slip it like crazy and rev it up hard to get any power out of the turns as I usually ride a gear high. Even riding in second where I should be just below the powerband it was falling on it's face. Anyone have any suggestions on where to start to try and get this thing back up to par?

2004 rm 250

powervalve adjusted out to engage smoothly

vforce 2 reed valves with fresh reeds

fmf gnarly pipe

pro circuit r304 silencer

No idea of hours on the piston. Just replaced it I think toward the end of last summer and I haven't ridden but maybe 7 or 8 times on it usually 1 to 1.5 hours of actual ride time

air filter has 3 rides on it but will be cleaned before I start troubleshooting

93 octane gas with belray powervalve hir 2 stroke oil mixed at 50:1

ngk br8es plug

main jet: 162

pilot jet: 48

Needle: NECJ

Needle set on second clip

Elevation usualy between 900ft-2800ft above sea level.

I have a pressure tester and I'm going to pull the tank soon and try and get a pressure reading (unsure if the pressure tester will fit.) I'm also going to put a fresh plug in it.

I don't know if it's the jetting is off due to the hotter weather but it's odd that there was that much of a loss of torque and it seemed to occur as soon as the ping showed up. It never came back the remainder of the day even after a 15 minute break. (I realize that's not enough to allow the engine to cool down.)

Please give me a direction. Anything else to try after pressure testing/trying a new plug?

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the ping is never a good thing. pull the plug and pray it does not have silver on it.

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