The journey of a piston circlip. ENGINE CARNAGE!

Not a cafe but I figured y'all would appreciate this. Took the GFs 1972 Kawasaki G5 (100cc rotary valve 2 stroker) round the block about a week ago. I made it about 2 miles and it just cuts out like I flipped a switch. Okaayyy..... call my dad and we get the bike home and I didn't get to look at it till today.



Spark? check. Compression? A tad low but should run. Fuel? Nada, plugs dry as a bone. So I pull the carb cause I figured something clogged it really good however unlikely that may be. Took a glance at the fiber rotary valve and spun the motor over, wtf? The valve is siezed! So the motor would spin but the valve was still covering the intake. Found my problem right!?



I pulled the rotary valve cover off and it looks like a goddamn paper clip jammed my valve and shattered the 45 year old fiber disk. It took me a second to realize what I was holding was a piston circlip.





Well I pulled the head and just had a couple minor scuffs on the cyl wall. Could catch a nail on them so I breathed a sigh of relief.

Then I pulled the cylinder to replace the wayward clip and I sucked that sigh right back in.







The clip smashed the intake port, gouging the lower piston and cylinder before catching on the fiber rotary valve where it siezed the valve and broke it loose from the retaining ring. A $0.50 circlip took out the two of the hardest parts to find on these bikes. Yay.

Anyone got a good source for a new cylinder and fiber rotary valve?

Sent from my SM-G930P using DO THE TON mobile app

Had one come out on a 350LC in 1987, did far more damage than that.

Sent from my SM-T560 using Tapatalk

lots of rotary valves on ebay even a nos one for 29$

there are some cylinders and pistons to

I did that before. Make sure that the gap in the pin clip is either at the very bottom or the very top. Otherwise the up and down of the piston can allow for the momentum of the clip itself to compress enough to come loose if the gap in the clip is at the side.

TheCoffeeGuy said:

I did that before. Make sure that the gap in the pin clip is either at the very bottom or the very top. Otherwise the up and down of the piston can allow for the momentum of the clip itself to compress enough to come loose if the gap in the clip is at the side.

Click to expand...

Now THAT...is some knowledge of experience. Great advice, glad I forget how I put mine in. Ignorance is bliss.