Y 29 Shims

I pulled two engines today and two heads. The old drag bike had every valve bent. I am going to install the 1075 engine in the drag bike. I pulled the head on the 1075 and i was showing a friend that the shims have diffrent numbers on them.

On the 1075 engine i popped two shims and they had Y 29 instead of the regular three digit number. Is this a aftermarket shim? Roy

Roy.Believe you have a couple of yamaha shims. depending on application may be small or tight. Yamaha's 26H would be loose, 1J7"s may be snug. I would replace any Y shim on GP. luck g, Bent valves indicate jumped cam timing. Look to tensioner, slipper and tensioner guide. the mushroom forest is usually caused by 2 or more skipped teeth. again luck G

Thanks for the quick reply.

I thought the Yamaha shims were bigger diameter. I have a lot of Yamaha shims.

This is a Mark II head. My other MarkII had regular shims.

The guy that built this engine has been a Kawasaki Mechanic before the H2 came out and raced for 30 years. Roy

the yamaha and kawaski shims are the same the suzuki shims were different they are 29.5 mm and have a bevel on the outside edge also some bmw's used the 29 mm shims as well

Thanks for the confirmation on ganes post.
I have so many parts from diffrent bikes i can get confused:silly: . I did tear down three Suzies and that is where the bigger shims came from.

The Kawasaki dealer ship that my mechanic worked at also went to Yamaha.

Where would i be without the people on this site.

I hope to ride next week if it warms up a little. We have had a couple of warm day latley. Roy

PS Gane, I don't know why the timing chain slipped. That is a chore for another day. I'll probably try and replace the engine since it is showing a lot of wear.

The rear motor mount bolt was bent and the sprocket cover was cracked. I imagine the bike has had a hard life of hard launches. Roy

roy-b
I could be, who ever road it last mist a shift. Better check the valve springs.
If the the springs are weak, you only get to over-rev once.
XENU

DISCLAIMER: i am in no way an expert, at anyting. anything i say is my own opinion and/or observation, and should never be regarded as fact, unless otherwise stated.

I am not going to do anything with the drag bike motor. It is junk. The head is junk. I pulled the springs out of it yesterday so i will measure the springs. I have boucoup springs.

The Mark II engine head was never retourqued after the rebuild and that may be the reason the head was seeping. The Mark II had a one piece head gasket and i replaced it with a two piece gasket.

Today i am going to time the cams and try and sort out the stator wires as they are diffrent from the KZ engine. Any help there would be welcome.

Thanks everyone for any input. Roy