My CDI hates me

stock heads are warped so it don't matter what gasket you use or what pressure they are torqued to.
you have to use sandpaper on glass to plane the head flat.
also see my ignition troubleshooting guide: http://www.dragonfly75.com/motorbike/testCDI.html

I understand this and checked my head and cylinder and it was fine well not that bad anyhow. If it was perfect you would not need a gasket. I have worked on many a 2 cycle motrorcycle engine that did not even use a head gasket. When I replaced nothing but to a copper head gasket funny how I now longer have to re torque other then once after about 20 miles like I did every time I rode with the aluminum?

I MILL my heads on a milling machine and not the ancient Neanderthal age way with glass or sand paper. I only talk about glass and so on trying to help those that do not have access to a MILLING machine.
Jeff
 
I do have access to a milling machine but I still usually go with the glass and grinding compound method. milling machine is quicker but you'll never get a mirror finish with one.

if I'm decking the cylinder I'll mill it down, just trying to make it seal it's getting the glass and grinding compound.

none of my engines have head gaskets, they just don't need them.
 
I do have access to a milling machine but I still usually go with the glass and grinding compound method. milling machine is quicker but you'll never get a mirror finish with one.

if I'm decking the cylinder I'll mill it down, just trying to make it seal it's getting the glass and grinding compound.

none of my engines have head gaskets, they just don't need them.

Really do not want a mirror finish. The little a mill leaves behind only help to retain the gasket. One of the things I wish I had is a mill but have a friend that has several.

Here is a case we fixed. The lip for the o-ring was 90% missing. Weld and machined.

 
when you're running without a gasket you want it as smooth as possible. mirror finish is a hyperbole but gives you an idea of the level of detail attainable.

here's a rechambered slant head I was working on before my camera quit on me. I still had some work to do on the squish band and one more stage of polishing to do, but you get the idea.

1jj0.jpg


you never realize how bad the stock heads are until you attempt to rework one, tons of little bubbles in the aluminum and the finish on all of the surfaces are horrible.
 
So I ordered a brand new kit. Installed and did a 4 tank break in. Bike was running perfectly. Went on a 20mile ride. After a 45 min break decided to return home. Now it seems my CDI is making a sound I can only describe as scatching/sqeaking/arching. When I WOT no noise whatsoever. Starting off noise. Low Rpms Noise. Idle no noise.

in the auto motive field when we run into problems like yours sometimes we wait til after dark or turn out the lights in a darkened garage then start the engine and spray the wires (in your case Wire) with plain old water. if your have a bad plug wire or exposed power wire it will show itself as a spark. you should not see a spark at all anywhere. if you do replace whatever is doing it and that will solve that. however i have never ever heard of a cdi making noise and suspect that what you are hearing is caused by another component on your ride. you can take a piece of cardboard and place it in front of your bike piece by piece to block out noise locally and try to identify the noise location that way and it won't cost a thing. use it like a shield so to speak.
 
I
when you're running without a gasket you want it as smooth as possible. mirror finish is a hyperbole but gives you an idea of the level of detail attainable.

here's a rechambered slant head I was working on before my camera quit on me. I still had some work to do on the squish band and one more stage of polishing to do, but you get the idea.

1jj0.jpg


you never realize how bad the stock heads are until you attempt to rework one, tons of little bubbles in the aluminum and the finish on all of the surfaces are horrible.

Thank you for this picture! I am going to invest a few hours if elbow grease to see if I can replicate this!
 
Found my issue. Blown head gasket... Let it sit for a few days and took a closer look.
 
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