- Aug 24, 2000
- 3,292
- 1
I just ran a search on this and didn't find quite what I needed.
2000 YZ250 Bone stock.
The last two rides I have noticed a power loss on the very low end. From a stop, I am having to use more clutch and gas to get rolling. The rest of the range is perfect, tons of power. I also noticed at a near stop landing on a cliff jump, that I had to slip the clutch to keep it from dying to complete the climb.. (Never had that problem before).
I have checked the obvious, no hanging up brakes, wheels spin free, no debris in the chain guide, etc. New filter and plug. The only thing I have changed before this started to happen is I dropped the pilot jet down one size because of plug fouling.
According to my sources, the jetting change should have, if anything, improved the low end by leaning it out.
Q. #1: Is my jetting information wrong, and the pilot jetting change is causing the power loss?
Q. #2: Could this be a compression loss problem? The piston and rings are original, but I don't have a lot of hours on the bike.
Q. #3: Could this be a power valve problem? I used to run bean oil through the bike and may have a load of crap built up in the power valve.
Thanks for your input!
2000 YZ250 Bone stock.
The last two rides I have noticed a power loss on the very low end. From a stop, I am having to use more clutch and gas to get rolling. The rest of the range is perfect, tons of power. I also noticed at a near stop landing on a cliff jump, that I had to slip the clutch to keep it from dying to complete the climb.. (Never had that problem before).
I have checked the obvious, no hanging up brakes, wheels spin free, no debris in the chain guide, etc. New filter and plug. The only thing I have changed before this started to happen is I dropped the pilot jet down one size because of plug fouling.
According to my sources, the jetting change should have, if anything, improved the low end by leaning it out.
Q. #1: Is my jetting information wrong, and the pilot jetting change is causing the power loss?
Q. #2: Could this be a compression loss problem? The piston and rings are original, but I don't have a lot of hours on the bike.
Q. #3: Could this be a power valve problem? I used to run bean oil through the bike and may have a load of crap built up in the power valve.
Thanks for your input!