OMR: '76 KZ900 Restoration/Modification

great, thanks for the info

Will ship it tomorrow Dave

this might be a dumb question but.....
Why are the valves surounded by a recessed area around the diameter?
Also the plug threads look to be pushed into this area
Would this condition not be better if it was smoothed out and feathered into the rest of the chamber?
Not trying to bust balls just asking
Jeff

LarryC wrote: Will ship it tomorrow Dave

Attachment daved.jpg not found

That's a beautiful thing! drool drool drool

Larry does fine work. I wanted to put my head up on the wall when I got it.

its nice but has no place sugestioning
thats its fine

that its fine

As to your original question, all the modern sportbikes have recesses around the valves like that. I imagine it has to do with combustion chamber airflow and flame propagation.

I'm sure Larry will explain it.

That's the way they're cast.

Chamber pics

The triangular section in the yellow circle sometimes gets removed. It depends on the size of the valves used. With 38/31 combo, there's not much of it let. I remove it so it doesn't cause a hot spot.

It can however help to reduce charge loss at certain RPM on overlap when the exhaust pressure wave is trying to suck the exhaust and the incoming charge out of the chamber. Everything with an internal combustion engine is a double edge sword. Helps one thing and screws you on another.. :S

ya right

jeffasaki wrote: that its fine

:dry: Whatever... Seems to me you don't even know what you're looking at based on your questions but you sure have an opinion.... Love the Internet :kiss:

Dave, you have some other head you're putting on the bike and sticking that one on the wall, yeh?