While cleaning up this mint example, I found numers stamped inside the ignition chamber. Wondered if there was any significance to these as they are not the part number?
No info on the numbers Henri...but the head is an early '10 bolt' one which still featured the combustion chamber shape used on the earlier '8 bolt' types...Ian
Thanks for that bit of info, I thought that the pocket was deep. Most of my other ones, have the filled in patch. How is that affect the power capacity? Or does it not at all.
Hi Henri..Compression ratio is the same for both types...changes made to the later type were done to improve combustion. I have never run the early type so can't make an objective comparison between the two in performance terms...Ian
Hi Henri, I had the same cylinder head on my bike. after changing it to the later head, the machine was running better. i dont know why, but i think the gasflow is a little bit optimzed on the later ones..
greetings jarek