Why is this KX100 getting harder to start?

[1tontj]

My GF has a 98 KX100. It has boysen rad valve, flywheel weight, and low gearing.
When we bought it froma guy in our bike club he said it had been rebuilt about 5 rides ago. GF has put about 25 more easy rides on it (she doesn't drive it too hard since we ride tight woods trails). It smokes and spooges, but almost always started easily in the first couple of kicks. It also has NEVER fouled a plug, and runs great with lots of power and no bogging.

Last little while though it has gotten hard to start. It has gotten a little colder (down to the low 50F's here right now)
but even on 70F days it is harder to start.

Ideas? Can I fiddle with it to make it run better easily (like air screw, or jet clip)?

Planning on tearing it down and rebuilding in a month or so anyway, just want to make it easier for her to start again for now.
She drove it all summer and always started it herself, but lately I have to help her because she can't start it, and she is frustrated by that.

Thanks,
Phil

 

[Vic]

It smokes and spooges, but almost always started easily in the first couple of kicks. It also has NEVER fouled a plug, and runs great with lots of power and no bogging.

It sounds like it's generally running rich and the plug has finally had enough. You may want to try a new BR9ES.

Dropping the needle (raising the clip) a notch should help it run better, assuming it is in good repair.

 

[1tontj]

I replaced the plug when it first got hard to start. No change. Plug was all brown on the electrode ceramic casing.

Phil

 

[MarkSims]

Check the reeds.

 

[KX02]

With the weather getting colder that bike will run leaner. So, if you are seeing spooge and smoke it may be because the top end is shot.

 

[1tontj]

Ok, well I guess she will just live with it for another month until I do the topend.

Was hoping maybe fiddling with the air screw, or needle position might help a little for now.

Thanks,
Phil

 

[sodflyer]

Did you check the reeds?

 

[1tontj]

No - i figured it can make it throuhg another half dozen rides unmolested, then I will tear it down for inspection/overhaul in a month.

How long do boysen rad valves usually go before the reeds need replacement anyway?

Phil

 

[sodflyer]

I don't know but if they have any seperation from the cage it could be the starting problem among other things. jeff.

 

[1tontj]

Ok, I will check it out - thanks,

Phil