G'day All,
I'm hope someone can help with this (possible) problem ...
My son and I have a state championship round coming up on Sunday so we thought we would put a new ring in his '99 RM125. Pretty straight forward really. Anyway, we replaced the ring and did a few heat cycles. My son took it out the next day and rode half a dozen laps of our small track. When he stopped the bike wouldn't idle but seemed fine higher up in the revs. He parked it until I got home and when I went to look at it he couldn't kick or bump start it. If you kicked it enough or tried to bump start it, it would backfire through the exhaust (more of a fluff sound really).
We replaced the plug, checked the spark (very healthy), checked the compression (OK), cleaned the air filter, checked the ignition timing (OK), checked the reeds (they are there) and replaced the fuel. We also pulled off and cleaned the carb (we found the pilot jet had some gunk in it). Solved, you might say. Well yes and no.
It took a bit to start it the first time (bump started) but it kick starts and idles and runs fine now. The strange thing is that, at idle, it now sounds VERY crisp (mainly noise from the expansion chamber) where as it has never sounded that way before. It was far more muted. The closest description I can give is that it now 'cracks' like a KX500.
I'm just not sure whether I sould be concerned or if the pilot jet has been clogged for a while and therefore its been running a bit 'flat'. The other thought I has is that maybe the powervalve is stuck open.
Any help would be appreciated or am I worrying about nothing?
Thanks.
I'm hope someone can help with this (possible) problem ...
My son and I have a state championship round coming up on Sunday so we thought we would put a new ring in his '99 RM125. Pretty straight forward really. Anyway, we replaced the ring and did a few heat cycles. My son took it out the next day and rode half a dozen laps of our small track. When he stopped the bike wouldn't idle but seemed fine higher up in the revs. He parked it until I got home and when I went to look at it he couldn't kick or bump start it. If you kicked it enough or tried to bump start it, it would backfire through the exhaust (more of a fluff sound really).
We replaced the plug, checked the spark (very healthy), checked the compression (OK), cleaned the air filter, checked the ignition timing (OK), checked the reeds (they are there) and replaced the fuel. We also pulled off and cleaned the carb (we found the pilot jet had some gunk in it). Solved, you might say. Well yes and no.
It took a bit to start it the first time (bump started) but it kick starts and idles and runs fine now. The strange thing is that, at idle, it now sounds VERY crisp (mainly noise from the expansion chamber) where as it has never sounded that way before. It was far more muted. The closest description I can give is that it now 'cracks' like a KX500.
I'm just not sure whether I sould be concerned or if the pilot jet has been clogged for a while and therefore its been running a bit 'flat'. The other thought I has is that maybe the powervalve is stuck open.
Any help would be appreciated or am I worrying about nothing?
Thanks.
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