PX wont start..the fecker

Problems with my '84 P125X again, the last couple of days it’s been an absolute bitch to kick up. Then last night about 3 miles from home the fecker died on me at traffic lights. Tried everything at the roadside to start it, changed plugs etc but no joy.
Got it home thanks to a mate with a van, and checked the carb the bowl was full of petrol but none seemed to be getting through to the engine. I’ve stripped and cleaned the carb, replaced it but it still wont start. I’m getting a good strong spark from my plug (NGK B6HS) So what do i need to check next? Any Ideas?
Cheers
Mark

You havn’t put the arm on wrong, and bthen being on reserve?
take the pipe off at the carb(just unscrew the 6mm bolt holding on the pipe to carb) and check petrol is getting through.[?[]

You should always have a look but often they go out the exhaust port. Thing to do is with the piston off shine a torch into the crank chamber. If there’s bits of metal in there you should really strip and but new seals in. Before we knew any better though a quick flush out with petrol suffised and we carried on with the rally season! That was in the good old days obviously!

Had same problem with my T5 in july turned out to be one of the piston ring had snaped.

Cheers for the reply Diablo, I should add ,whilst tinkering with the carb i’ve found that my petrol tap pin had snapped through the rotor so my petrol could have been left on for ages without me knowing, would this have any effect?
Cheers
Mark( on the bus to work this week [:@] )

Hi its a pleasure to help. Can’t remember what the std size is but just ask for a 1st oversize piston and get a rebore as well.

I tried putting thinnners in the plug hole and kicking it over but i got nothing at all. Think a top end strip down might be beyond my limited capabilities.How much would i be looking at for a complete strip down and rebuild with new seals and gaskets?

Had same problem with my T5 in july turned out to be one of the piston ring had snaped.

Diablo and gaz, you were both spot on took the cylinder head off and both the rings had gone, looks like one had completely disintegrated and the other one was snapped, the cylinder was burnt and the head scored and pitted, i’ve had a look on the VE site and beedspeed and notice the kits come in different sizes, if mines a standard P125X what size should it be?
Thanks again for all your help boys
Cheers
Mark

it will only have an effect if its flooding your bike. This will make it difficult to start but doesn’t explain you conking out and not being able to restart. Saying that fix things as you go when trying to identify a problem as there’s often more than one acting at the same time!

Is the plug wet when you check it?Usually if you are getting petrol into the carb but none to the cylinder head it usually points to ring failure. Have you lost compression? If the rings arn’t sealing all the fuel goes out the exhaust port. Get some thinners or another highly flammable liquid and put a small amount in through the spark plug hole. Replace the plug and see if it will fire up. It should for a very brief period. If you still can’t get it to start its a top end strip im afraid.
Theres a few variables here so I could be wrong but it sounds like it could be this. If you’ve still got a little compression you could prove the theory by bumping it down a hill so you get the motor spinning quicker than you can kick it. If it starts but wont rev freely or tickover then its the rings. As I write this ive thought of something else it could be which is the drive side oil seal breaking up-either way its bad news, sorry.

Just a question as an interested observer. If both piston rings have disintegrated - is there likely to be damage elsewhere in the engine from the pieces of engine ring?