Head Stamp

According to the Haynes manual "cylinder heads are identified by a part number and code stamped on the right exhaust rocker box face." (i.e. RH3, RH6, etc.) I will be darned if I can find it. Can anybody help me out? Either I am looking in the wrong spot or it doesn't exist.
Thanx.

I don't think 750 heads were stamped except the combat with the C. if 850 it could be around the rocker spindle area.

I've seen RH5, RH6 and RH7 stamped on 750 heads, early ones didn't seem to have a stamp though, and RH4 and RH10 on 850s, combat ones tend to just have the C on top

Usually stamped right above the right side exhaust rocker cover. If you look carefully, you can see the RH7 stamped in this head.



Ken

Looks like the top four fins have been added. Does an RH7 have four additional fins or was this head modified? If so, why?

Thanx for the photo! It helps a lot to know what I am looking for. The stamp isn't there on my head, bit it helps anyway, for future reference if nothing else.

Prior to today, I had pulled the three bolts securing the head steady to the head and pulled the plate up far enough to shine a good light under there and was not able to identify a mark. I stopped there as the rubber on the head steady was about to part and I didn't want to wrench on it. I wanted to do a few more road trials to work up the winter project list and figured any head steady would be better than none. Anyway, I finally pulled it all the way off this morning (yes the rubber broke when I wrenched it) and found the "C" stamp. It was a bit higher on the head than I had anticipated and the relief was not deep enough to see it with the light at an angle. I am referring to the relief of the stamp, but my relief is fairly deep as this is a significant piece to the puzzle.

Thanx again.

Russ

lcrken said:

Usually stamped right above the right side exhaust rocker cover. If you look carefully, you can see the RH7 stamped in this head.

Ken

Click to expand...

Ken,

Very nice and rare RH7 short stroke 750 head. Do you have the machine it came with?

The head is one that was used on one of Ron Wood's flat track bikes. The extra fins are not from Norton. The head was ported and modified for even larger valves by C.R. Axtell, and I suspect he is also the one who welded the fins on, but I'm not sure. Axe did almost all the engine development work for Ron back when he was running the Norton flat track bikes. Here's another shot of the head from the other side.



Ken

Sorry, David. I didn't really answer all of your question. No, I don't have the bike it came on. I bought it from Ron as a bare head. The only reason he finally agreed to sell it to me was because it needed a lot of repair. I've done some of it, but still have to install some inserts for the studs, install new valve seats, make up some new guides with larger outside diameter, and make some valves. The quality of Axe's work was so good that I think it will be worth the effort, but I don's seem to get around to working on it very often. Life is short, and motorcycle projects go on forever. Here's another picture, showing the combustion chamber. You can see some of the problem with the intake seats.



Ken

That is a very nice piece of history you have there, Thanks for sharing the pictures with us.