94' KX125 Problem - Possible Engine Seized? - HELP!

[WantEXA]

I've got a kx125, hadn't been ridden for about 7 weeks, started her up today as i was taking her out of my suburb and a few km away to somewhere with alot of bush tracks.

Warmed her up for a couple of minutes as she hadn't been run for so long and took it up and down the street not hammering it at all to make sure everythin was ok.

Started out heading up the road, noticed she was blowing alot more smoke than usual, i figured it was just because it hadn't been run for so long.

I stopped by a friends house, then left pretty well straight away, i got another 2km away and was going up a hill, i downshifted from 5th to 4th (didn't over-rev as far i could tell, i just wanted to stay in powerband) was going roughly 80km/h and all of a sudden (about 2secs after i downshifted the back wheel just locked up and slid for a good 10M or so, and then is freed up and started turning the motor over again but it didn't start.

Engine hasn't run since, the radiator cap felt hotter than usual and i can still kick the engine over.

The engine must have seixed as some stage for the back wheel to lock up but maybe the force of the wheel unseized it. when it cooled a couple of degrees as the bike was sliding.

When the bike was just sitting there there was drizzle of smoke coming out of the exhaust pipe, which i know isn't normal and it smelt strange. It was doing this for a good 10-15minutes

I know tsomehtings mega ****ed up here, but does anyone know what it is? and how much its gonna cost me? I'm trying to sell this bike so i need it fixed without to much cost! But the main thing is i'd love to know the problem and what it needs

Cheers

Chris

[kashlak]

Whats sweet about 2 strokes is it will only be about $100 to do a top end rebuild. If thats all that has to be done. Does the compression still seem to be normal? Drain the oil and see if there are any metal chunks in it.

[WantEXA]

Yes compression still seems fine... i'm assuming this would mean it wont be too bad to fix on the pocket?

Is it worth doing it myself or is it better just to pay somebody? I'll need a torque wrench which i dont have

I'd like to know what caused it though, and exactly what the problem could be, if anyone could tell me by the info i've given.

I'll drain the oil as soon as i get a new bottle

[project_mx_37]

Did you use the same premix that was in there 7 weeks ago?? 7 week old fuel would have lost almost all of it lubracative properties, and therefore, may have cause the problem.

[WantEXA]

shit, that'd be it ay... thanks for that!

So piston/rings/rebore?

[SirHilton17]

I highly dought that 7 week old fuel would loose all of its lubrcating properys

[project_mx_37]

you will be surprised, even the manual says it,

[project_mx_37]

i ran 4 week old premix through my 2005 KX250, and my boss grilled me for it, sayin i can sieze the bike bad, if i do it again. The 250 was fine, it wasnt affected, but 7 weeks maybe gettin a bit to old, or then again, its a 94 model, so it gettin on a bit too., siezing the top end will mean replacing the piston, rings, the (pin and bearing and circlips you should replace everytime u change the piston. the cylinder may be honed, depending on how bad it is.

[kevin204]

Was it colder than it was last time the bike was ran? The engine could have cold seized if you didn't rejet it. If it did cold seize, you might be able to get away with just a hone job.

[WantEXA]

nah it woulda been hotter i'd say... the engine overheated too i'm pretty sure, due to the smoke coming from the pipe even when the bike wasn't running

[CRF50Racer]

It sounds like you siezed your engine... your piston could have expanded due to overheating and siezed, but then broke free again... just pull off the top end... your piston is probably scored... even if your engine can still run, doesnt mean that the top end is good.