- Jun 5, 2001
- 7,529
- 18
Trust me on this one, there's a problem with the two piece power valve on the 01 RM 250. The upper portion tends to stick to the inside of the chamber causing a polished looking ridge around the edge. Obviously, I experienced this 1300 miles from home and not at the local track.
I polished the top of the power valve and cleaned it and the chamber completely. This solved the problem but what I found was that prior to this, after the bike reached temperature, it would expand the steel valve causing it to stick in the port. This also caused strain on the actuator which then broke near the lower end.
Preventive maintenance would be to keep the valve clean and pull it out and polish the top portion nearest to the piston. Also, when tearing the valve apart, there is an 1/8" diameter pin approximately 4" in length that goes through the lower portion of the power valve. If this pin is not placed back in the same way it was taken out, it causes the valve to stick, even if you polished the valve. The pin works itself into the two metal cams on each side and it works one way. Even though the pin looks the same on each end, it won't work smoothly, trust me.
I was told that a 1999 power valve, springs and cams work better in the 01' motor but I'll probably stick with what I've got now that it works.
Just some info for anyone to save the headaches I had during DW!;)
I polished the top of the power valve and cleaned it and the chamber completely. This solved the problem but what I found was that prior to this, after the bike reached temperature, it would expand the steel valve causing it to stick in the port. This also caused strain on the actuator which then broke near the lower end.
Preventive maintenance would be to keep the valve clean and pull it out and polish the top portion nearest to the piston. Also, when tearing the valve apart, there is an 1/8" diameter pin approximately 4" in length that goes through the lower portion of the power valve. If this pin is not placed back in the same way it was taken out, it causes the valve to stick, even if you polished the valve. The pin works itself into the two metal cams on each side and it works one way. Even though the pin looks the same on each end, it won't work smoothly, trust me.
I was told that a 1999 power valve, springs and cams work better in the 01' motor but I'll probably stick with what I've got now that it works.
Just some info for anyone to save the headaches I had during DW!;)