Engine cut out and Back wheel lock up

domthecondom

domthecondom

domthecondom

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Joined
9 Jul 2008
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Bristol
Hi guys,

Had an odd problem on the way home on my Husqvarna WRE 125 (2 stroke)

I was having electrical problems before (think it’s the Digital speedo draining the battery) so when I think I fixed it I took it out for a test ride.

I was ridding home when randomly my bikes engine cut out and my rear wheel locked up whilst I was doing around 30 mph (pulled clutch in as soon as I realised what was going on). I tried to kick-start it (took around 10 minutes) before I rode down the road and the same thing happened to me.

I thought it would be better to push it home and when I got home I wanted to kick the bike over but now my Kick start will not move for toffee.

Anyone got any idea what could cause this? Could my top end have gone?
 
Sounds like the top ends gone, running it again wouldnt have helped.

New piston/rings and maybe a new barrel will be required
 
Initial stop was a heat seizure & it sounds now as if the rings have gone & the piston is seized in the barell.
I'd check your 2 stroke oil delivery system.
You can do this yourself though don't be scared it's easy to replace a piston & rings on a 2 stroke.
 
Kick start mech jammed? Had this happen on my wife's old scooter, the mechanism worked loose inside the engine casing causing the engine to cut out and jam. Could kick it over until it jammed solid properly one day.
 
yeah something has seized inside,could be the generator nut comeloose and jammed could be something more serious
 
The symptoms pretty much conclusively point to a piston seizure. This can occur either through overheating (weak mixture, incorrect ignition timing, insufficient coolant etc), through lack of lubrication (oil tank dry, failed or incorrectly adjusted oil pump), or through insufficient piston or ring gap clearance.

Budget for a new piston and rings, gasket set and most probably a new barrel (especially if it's a chromed alloy bore). Obviously the underlying cause of the problem must be found and fixed or it will simply happen again.
 
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Cheers guys :) I will be fixing my 4 stroke XR 125 first then post some pictures of the 2 stroke insides once the 4 strokes on the road.

How would I know if a new barrel is needed?
 
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If the surface of the bored has been damaged (e.g. scored) and it's not possible to re-bore it (like e.g. chromed alloy) then you will need a new one. Barrels that use a cast iron liner can usually be re-bored and an oversize piston and rings fitted, but the majority of modern two stroke engines use the chromed alloy bores.
 
Same thing happened to my TX50X about 200 miles after putting the 70cc bore kit on it. Rings went and the piston locked.
 
you probably have to have it re-nikasil lined,dont let them shove a normal sleeve in it,it wont last five minutes it has to be nikasil plated
 
Ok Bike is fixed..... It was a Piston Seizure.

When I drained the Engine Oil....a lot of water came out.

Got told the when the water heats up it would have steamed up and taken all the lubrication of the Piston.
 
Two stroke does not use engine oil to lubricate the piston or crank.
Do you mean you had water in your 2 stroke oil tank.
You were told crap tbh.
 
the head gasket could have blown? water got into the cylinder and cant compress so locked up? if its water cooled then that could happen
 
Sorry I should have told you that I pretty much went swimming with the bike....

So water could have also got into the cylinder....but the engine oil also had a lot of water in it.
 
Won't be a dry gearbox now will it.

No it would not be, but it is sealed from the crank as you prob know.
It should not get into this area unless the crank seals or gasket has gone.
Still does not make sense what to op said.
Water could only come from - 2 stroke oil - fuel or the crank seal ect has gone which would ask the question how the hell did water get into the gear box area:confused:
Or as as already said it is water cooled - head gasket.
 
There would be a gearbox breather, if he's submerged the bike during this swimming exercise water could enter that way.
 
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