So my GF's bike is a 98 KX100 and it is having problems.
We bought it used. It has a boysen rad valve in it.
Ran great all last summer. Great bike. Never fouled a plug, and always ran great. It did seem to smoke a slight bit more than you would expect. We figured since it never fouled a plug it must be ok, and might be because my GF does not rev it up enough to clear the smoke out of it. Though it even smoked some visibly on the fire roads going 50mph...
But it never fouled.
We in the fall it got so it had less and less bottom end. It also got so it was harder to start when it died. Changing plugs did nothing. Suspected it needed a new topend as we had made zero changes to it. If it was jetting, it should not have gotten gradually worse right? I am asking - I am no two stroke expert, just a diy home mechanic with no real training.
Well by the last ride she took on it in the fall you had to slip the clutch a lot to get going in first. After that it was great (wheelied no problem with me riding it) just no bottom end.
So, I got a new piston/rings/gaskets and tore it down and rebuilt it. Everything seemed to go together fine. I also took the carb apart to clean it, but was happy to see everything nice and clean inside. Reed valve seems good too. No chips or cracks, can only see light through between the petals and the housing if it is held up to the light.
Put fresh gas in it today and drove it around the yard (once it warmed up good) to try it out. It was just below freezing out, so I didn't want to run it much. Started it in the warm garage to warm up, then took it outside for a quick trial.
Still bogs off the line and requires slipping the clutch. Still goes plenty good at hig speed. Something I noticed - if I put the choke on, then it runs better (not perfect but much better).
So, what should I check guys?
Thanks a lot,
Want to get my GF's bike running well, riding season starts in 4-6 weeks...
Phil
We bought it used. It has a boysen rad valve in it.
Ran great all last summer. Great bike. Never fouled a plug, and always ran great. It did seem to smoke a slight bit more than you would expect. We figured since it never fouled a plug it must be ok, and might be because my GF does not rev it up enough to clear the smoke out of it. Though it even smoked some visibly on the fire roads going 50mph...
But it never fouled.
We in the fall it got so it had less and less bottom end. It also got so it was harder to start when it died. Changing plugs did nothing. Suspected it needed a new topend as we had made zero changes to it. If it was jetting, it should not have gotten gradually worse right? I am asking - I am no two stroke expert, just a diy home mechanic with no real training.
Well by the last ride she took on it in the fall you had to slip the clutch a lot to get going in first. After that it was great (wheelied no problem with me riding it) just no bottom end.
So, I got a new piston/rings/gaskets and tore it down and rebuilt it. Everything seemed to go together fine. I also took the carb apart to clean it, but was happy to see everything nice and clean inside. Reed valve seems good too. No chips or cracks, can only see light through between the petals and the housing if it is held up to the light.
Put fresh gas in it today and drove it around the yard (once it warmed up good) to try it out. It was just below freezing out, so I didn't want to run it much. Started it in the warm garage to warm up, then took it outside for a quick trial.
Still bogs off the line and requires slipping the clutch. Still goes plenty good at hig speed. Something I noticed - if I put the choke on, then it runs better (not perfect but much better).
So, what should I check guys?
Thanks a lot,
Want to get my GF's bike running well, riding season starts in 4-6 weeks...
Phil
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