Some of you may now that me and my lad have been rebuilding an old ts50x for him to start riding, anyway got it mot'd on Sat (flew through) and have just got the insurance cert through so James went and got it taxed.

I comes in from work and take it out for a shake down and after about 30 minutes it badly lost power and made some strange noises so came home, kept stalling whilst I tried to get the mixture set up right as you can only do this when the engine is hot, during kicking it off the piston decided to jam up, probably as the cylinder had started to cool, it seems as though a ring has come adrift and it jamming into either the inlet or exhaust port as I cant lift off the head, it jams when sliding it up.

Any ideas how I can proceed or is it a case of 2 blocks of wood under the lifted cylinder head and then tap down on the piston while trying to keep debris falling into the crank?

Any ideas? I know somebody that can do a re bore but do I get a piston and he re bores it to that piston or the other way round, re bores it then gets a piston to match?

Cheers

Rich

usually pistons come in "stepped" std sizes when a rebore is being done, get the piston & rebore to that.

just an idea, poss reason for a ring getting caught is that the ring gap has moved around the piston & caught on the inlet port, i believe that engine has a tiny little pin that the ring locates into to stop this happening.

how,s you by the way?

all the best
andy

Ouch - Unlucky mate

I would find out what pistons are available and bore to what you can get hold of.

For getting the head/barrel off, can you see down the ports to push the offending ring out of the way with a screwdriver?

Just got one off the bay for £14 inc postage which I think is fair, its a 1.50mm oversize which should be ok as there is some nasty score marks.

When the goings got tough I've called in my dad He's coming round to help tomorrow. Dads are great aren't they...

Cheers

Rich

Check the oil pump calibration! (And oil level!)

Yep, did that when fitting the throttle cable, two lines on the oil pump and little dot on the needle assy. Will check though!

Cheers

Rich

Arghh, the glory days of 2 strokes.. seized many a single, twin, triple (middle piston)

My Suzuki X7 used to eat pistons and score barrels for fun!

Block of wood on top of the piston just to get it unstuck then lift the barrel off. May need a fair bit persuasion but don't be going at it with a 14lb mel hammer!

Keep the 2 stoke mix heavy while your fiddling with the mixture and remember its better to be way rich than weak....

Steve

This is a true story, please don't laugh.

Used to be a bit of a pro at blowing up 2 strokes, changed my first piston at about 12 years old.

Holed a piston on a TS 125 X when I was 17, my mate legged it down to the bike shop to get me a new pistion.

I started stripping and to get the bits out of the bottom end, I filled it with oil and started pressing the kick start. Had the odd bit come to the top, it was working well.

Mate turned back up, quickly put new piston in, rushing to meet the new lady in my life

I couldn't kick the b*stard, I was like the piston had seized, but it would move a little. After a couple of hours of fannying around I realised I hadn't tipped the bike over to get the oil out

Emptied the oil, filled with petrol to flush and away to go. She smoked a bit for a few miles

quote:

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Originally posted by coozer
Arghh, the glory days of 2 strokes.. seized many a single, twin, triple (middle piston)

My Suzuki X7 used to eat pistons and score barrels for fun!

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