Topic: Cyclex MLS head gasket question?

[PeWe]

I used the kitchen table...
Head had bad surface since rough machining marks during the 80's, marks that had to be removed. 240 grit paper to remove it. Then 400grit for smooth surface.

Did the same with cylinder.

I had to replace the wet sandpaper very often. I replaced the 240 paper minimum 4 times/head or cyl plus same with 400 grit. Wet and it become fragile and not flat when it was glued and taped on the surface. Extra tricky when it was 2 papers side by side and they started to cause problems in the middle.

 I checked flatness during the process with help of a marker pen I wrote on the surface. If flat the markings should disappear simultaneously on the entire surface.
In the end I did not trust the flatness, I continued with fiber has I have used before.

[jhalldorson]

Wow. Your stuff looks great. Only a straight edge could say for sure, but I would bet its straight enough.  I kinda felt better after I took it apart to sand it down. I found sealing witness marks around all the areas that mattered. Going to cross my fingers and proceed now.

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[70CB750]

Looking great, PeWe!

My first CZ engine was split in the middle and to make it seal I done it using lapping compound on a plate of glass - but the principal is the same.

[PeWe]

The good thing is no leak. I have tested the engine. The job above was end of May 2012.
Now head off since I needed to replace valves and do the seats properly.
Cometic fiber gasket going in when I get back my head from the local tuner that ported it 30 years ago.

I restored more and better along the restoration process. Better than I planned 4-5 years ago.

[jhalldorson]

Have you had your bike that long pewe? Since it was new?  I was reading a little about your valve train. Sounds crazy complicated. I guess I never knew your country had Honda's and were so into performance.

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[PeWe]

I found the used bike at a dealer January 1979. It had been used 2 summers then, 77-78. Imported from Japan Oct 1976.

CB750 is not complicated at all, especially now with this forum where I can find tons of facts and experiences written by professionals that have working with CB750 since it was released. Plus all others restoring/repairing the bike.