by Coolbreeze » Sun Feb 17, 2019 2:16 am
I am learning more about K model heads here than I dreamed was available. I got my original '56 KHK when I was a teenage farm kid studying engineering at Univ. of Ill. Then, when my heads cracked, I just called Hank Reiman (Roger's dad) and had him ship me KR heads because that was all he had. The bike ran fine with those heads; so, I figured there was not much difference. Recently, I swapped out the heads on my current '56 KHK and found there was a clearance problem with long thread spark plugs. The bike seems to run fine with the shorter thread plugs, but it seemed strange that there would be a difference. Now, I see a possible explanation: The replacement heads give more compression but less flow. I am not racing the bike; so, if it is happy with these heads, I shall be happy.
If I ever swap heads again, I will take note of the casting numbers just to know what I am putting on the bike.
'56 KHK
'60 XLCH
'48 Chief
'42 Indian 841
'64 BMW R69S
'84 Moto Guzzi V65Sp