Head Opinion Request

This is how my head looks 2000 miles after head job. Is this normal with the exhaust valves lighter than the intake or do I have issues. Tops of the piston are kinda black with very little carbon. My inclination is to think this looks good but I am not yet experienced enough to know for sure.

Very typical appearance of a decent burn (good jetting). If over-rich, the exhaust valves would be sooty; if too lean, the intake valves would be lighter.

Maybe not perfect, but not too bad.

Close enough to put a high polish into the chamber and re-fit it. JMO

Light carbon on crowns and good color on valves, about as good as it gets.
Anal chamber polish helps reflect heat into torque and less carbon foot holds.
Some water spraying into carbs while blipping up turns carbon to soft grey dust that blows out exhuast. Can not hurt engine with hydro lock as engine stalls long long before that. Just restart and blip higher or a bit less spray till fairly clean looking exhaust. Boiling pistons in water can almost soften carbon to wipe off.

Why did you remove head?

Looks OK to me, but I'd be a concerned by what appears to be a deep score in the edge of the left chamber. If it is, it may burn the head gasket. The stain around the perimter of the head flange - was this a sealant? If you use the best head gasket the composite Victor Reinz brand you should not use any sealant at all. Back to the mystery - why did you take the head off?

Mick

Thanks for the heads up on best composite gasket ml.
The hottest set up on Ms Peel was a standard port and CR head, but it had gas jet cuts from bore to the push rod tunnels so I put hi temp standard JBWeld in them and used razor blade and good file to make flush and it held up fine over time and very hard hot long usage. I blew a cheap gasket at the oil drain hole but the JBW stayed fine on a few head off and on's. DIY w/o risk of welding distortion.

ML said:

Looks OK to me, but I'd be a concerned by what appears to be a deep score in the edge of the left chamber. If it is, it may burn the head gasket. The stain around the perimter of the head flange - was this a sealant? If you use the best head gasket the composite Victor Reinz brand you should not use any sealant at all. Back to the mystery - why did you take the head off?

Mick

Click to expand...

I am doing a crankcase swap out. I got a set of late 72 cases that I have machined. The bearing were starting to go also, confirmed on teardown.... opps.... I'm sorry disassembly.

Still waiting for other shoe to ...
Why new cases and what was machined on the Combat replacement set?

Inspect Very Close, no I mean DynoDave close, for cracks in the stress risers of mounting flats where Norton machined a sharp corner. They can be so fine it takes strong light and strong magnification or even stained to see. I assume you are aware to the wet sump at speed issue Combat cases have and the mod to avoid that.

hobot said:

Still waiting for other shoe to ...
Why new cases and what was machined on the Combat replacement set?

Inspect Very Close, no I mean DynoDave close, for cracks in the stress risers of mounting flats where Norton machined a sharp corner. They can be so fine it takes strong light and strong magnification or even stained to see. I assume you are aware to the wet sump at speed issue Combat cases have and the mod to avoid that.

Click to expand...

Old Cases had a bad hole for the idler on the timing side, an all but stripped drain plug, they were an early 200xxx unreinforce cases. I had pulled old piston ring schrapnal out of the oil pump port and could not be sure as to the condition of the sump hole.
New cases are the late reinforced type 210xxx. machined out the the sump for that update, added threaded inserts to drive side primary mount and drain plug, added a one way valve from grandpaul as seen in other posts. New superblends and a stage 1 cam kit from JS. Along with a gearbox overhaul, a rear iso update, freshen the swingarm and, fork seals and rework the side stand will round out the winter project.