I recently bought a 98 XPL. I changed fuel lines and bypassed selector valve. Took carbs apart and they had brand new OEM rebuild kits in them. Verified everything was to stock spec as per the service manual. The first couple times I took it out, it ran really well except it misses in the midrange from about 3500 to 5200 rpm. Not enough to hurt performance drastically, it easily powers right through it. You can just hear it. Then last time I had it out, if you kept it wot for more than a few seconds, it would fall off about 500 rpm. I don't know if that's related to the missing or not just thought I'd mention it in case. Since I'm pretty sure the fuel system is good, I'm thinking maybe electrical? What do I check first? Is the rectifier built into the mpem on this one?
98 XPL Missing
- Thread starter jcgossen
- Start date
The "Missing" at 3500-5000 is perfectly normal. It is a resonance wave as the ski is transitioning "on the pipe" and the RAVE valves and pipe are starting to come into play.
2-strokes work on a resonance wave that scavenges the combustion chamber, it is actually a really interesting thing to get too far into.
If you start to drop rpm in sustained WOT that could be a bad thing and starting to run lean.
Try opening up the HS screw about 1/8 turn and see if it gets better or worse.
2-strokes work on a resonance wave that scavenges the combustion chamber, it is actually a really interesting thing to get too far into.
If you start to drop rpm in sustained WOT that could be a bad thing and starting to run lean.
Try opening up the HS screw about 1/8 turn and see if it gets better or worse.
That's what I was wondering... In a way it seemed normal to me but then I compared it to all my other 2 stroke skis and none of them sound quite like that. But this is my first 951. I don't even notice it anymore when I ride it but the other day my wife rode it and she headed off across the lake and I could hear it "missing" till she disappeared. She must have been holding it right in that range. I know she wasn't going very fast. I'll try the hs screw thing thanks for the help.
