VxZeroKnots
Gold Level Site Supporter
I have a 2012 300EC with 123 hours on it. New piston and rings at ~105 hours, new plug at the same time. Power valve adjustment was checked and it needed no changes at that time. Air filter was on it's first ride since cleaning when the problems started.
Just yesterday I was riding in the mountains and on the way back to the truck riding back on the road the bike started blubbering and had no power right at about 1/4 throttle, maybe a little above. It ran fine all day doing everything from 1st gear clutch slipping Romaniacs style gnar to 6th gear fire roads for miles.
After the last bit of single track we got on a dirt road and then had about two miles of pavement before the truck. About a mile and a half into the pavement cruising at a good clip around 1/3rd throttle the bike just started to blubber and had no power. I stopped, checked I had plenty of fuel, switched to reserve anyway and rode another few hundred feet with similar results. I had my buddy tow me the last little bit back to the truck just to be safe but probably could have limped it in.
The bike starts and idles fine and runs normal until about 1/4 throttle. I took the exhaust apart and checked the packing and spark arrestor. The sparky is clear and I'll replace the packing since I'm in there but nothing looked out of sorts. I then checked the plug and it was not fouled and was a light brownish tan. Looks just like the plug I pulled out of it that the bike ran 100 hours on.
Carb is a Lectron 36mm with the needle at 1/4 turn rich from 50.28 (made a field adjustment and haven't measured it since) and the power jet is at 1.75 turns out which I think is a touch rich. Elevation was about 8k feet and temps were in the 60's so I feel everything is spot on there. I haven't checked the carb for debris yet.
If the carb checks out I'm guessing maybe my power valve is stuck or one of the bearings in the governor became dislodged perhaps. My understanding is you remove the exhaust side cover and run the bike on the stand to see if the lever actuates. Is that correct?
I won't get to check that until Tuesday when the shops open and I can buy some exhaust packing since all I have on hand right now is 4t packing. I plan to take a peak into the cylinder through the exhaust port when I pull the pipe just to make sure the rings and piston are happy but the engine never stalled or froze up and starts and idles fine so I'm assuming they are good.
If anyone has any ideas or input beyond that I'd really appreciate it and am all ears. I'd really like to be able to go ride again next weekend so any trouble shooting tips or pointing out something I'm missing would be greatly appreciated.
Thanks in advance!
Just yesterday I was riding in the mountains and on the way back to the truck riding back on the road the bike started blubbering and had no power right at about 1/4 throttle, maybe a little above. It ran fine all day doing everything from 1st gear clutch slipping Romaniacs style gnar to 6th gear fire roads for miles.
After the last bit of single track we got on a dirt road and then had about two miles of pavement before the truck. About a mile and a half into the pavement cruising at a good clip around 1/3rd throttle the bike just started to blubber and had no power. I stopped, checked I had plenty of fuel, switched to reserve anyway and rode another few hundred feet with similar results. I had my buddy tow me the last little bit back to the truck just to be safe but probably could have limped it in.
The bike starts and idles fine and runs normal until about 1/4 throttle. I took the exhaust apart and checked the packing and spark arrestor. The sparky is clear and I'll replace the packing since I'm in there but nothing looked out of sorts. I then checked the plug and it was not fouled and was a light brownish tan. Looks just like the plug I pulled out of it that the bike ran 100 hours on.
Carb is a Lectron 36mm with the needle at 1/4 turn rich from 50.28 (made a field adjustment and haven't measured it since) and the power jet is at 1.75 turns out which I think is a touch rich. Elevation was about 8k feet and temps were in the 60's so I feel everything is spot on there. I haven't checked the carb for debris yet.
If the carb checks out I'm guessing maybe my power valve is stuck or one of the bearings in the governor became dislodged perhaps. My understanding is you remove the exhaust side cover and run the bike on the stand to see if the lever actuates. Is that correct?
I won't get to check that until Tuesday when the shops open and I can buy some exhaust packing since all I have on hand right now is 4t packing. I plan to take a peak into the cylinder through the exhaust port when I pull the pipe just to make sure the rings and piston are happy but the engine never stalled or froze up and starts and idles fine so I'm assuming they are good.
If anyone has any ideas or input beyond that I'd really appreciate it and am all ears. I'd really like to be able to go ride again next weekend so any trouble shooting tips or pointing out something I'm missing would be greatly appreciated.
Thanks in advance!
