Got my first dirtycycle!

[Fast_Eddie]

Check that the power valve hasn't become so sloppy that the side touches the piston skirt.

[typeone]

^ good thought ^

[REXXX]

I have to drain the oil still, take the motor out, then clean out the debris. Then really look over the head, cylinder, pump and so on.

It broke on the intake side this time, exhaust side the first time.

[breakdirt916]

yep, f'ing headache

where it shattered - which side is the the piston bent? in or out? did it smash into the edges of the cylinder on the intake side?

[REXXX]

Went to sell it today and the person who was thinking about buying schooled me on dirt bikes a little and noticed a vibration which did not seem normal to him, I had thought it was the way a 2 stroke ran. He said when it vibrates like it does it usually means the crank main bearings are getting very old and will cause the piston to ride an edge of the cylinder wall and cause chaos. He didn't buy it but gave me some good insight.

[breakdirt916]

yep...I forgot about that!

that could possibly explain your woes...the crank bearings are gone, and that's what's causing the piston to move off-center, and shattering that piston skirt

this is why I did a whole overhaul on the RM engine - new transmisison bearings, new crank bearings, machined the cases to fit perfectly, trued the crank to spin straight, replaced all the seals, washers, spacers, fasteners, drilled out any oval holes, re-rounded them, and burned in new seals, new water impeller...everything.

after taking the thing apart, I realized that inside of a 2-stroke is delicate, and all the parts need to be in full operational shape and working in harmony for me to be confident that something doesn't explode causing an even more expensive repair.

but regardless, I'm glad you learned a thing or two...now you just need to cast the net wide, keep showing the bike to as many people as posisble, and find someone who can't tell a loose crank bearing from a loose brake lever, and will just buy it because it runs.

[REXXX]

yep...I forgot about that!

that could possibly explain your woes...the crank bearings are gone, and that's what's causing the piston to move off-center, and shattering that piston skirt

this is why I did a whole overhaul on the RM engine - new transmisison bearings, new crank bearings, machined the cases to fit perfectly, trued the crank to spin straight, replaced all the seals, washers, spacers, fasteners, drilled out any oval holes, re-rounded them, and burned in new seals, new water impeller...everything.

after taking the thing apart, I realized that inside of a 2-stroke is delicate, and all the parts need to be in full operational shape and working in harmony for me to be confident that something doesn't explode causing an even more expensive repair.

but regardless, I'm glad you learned a thing or two...now you just need to cast the net wide, keep showing the bike to as many people as posisble, and find someone who can't tell a loose crank bearing from a loose brake lever, and will just buy it because it runs.

If I had the time, tools for splitting, and space I would love to take it apart and rebuild it completely. Life is taking me in a different direction for the next 6 months so I won't e able to do that and would like to alleviate some debt.