Cylinder head chamber shape

[Fabian]

I will all so be balancing mine as this has a lot to do with life expectancy.

A single cylinder engine cannot be balanced.

 

[45u]

A single cylinder engine cannot be balanced.

I disagree you can do a very good balancing job if you disable the crank. No a Harley is not a single cylinder but uses a male and female rod with only one cowmen crank pin and I balance them all the tine.l Been doing it for 40 plus years. To do these cranks I will have to machine mandrels for it.
​

 

[45u]

This is what I use to balance HD wheels.

 

[FurryOnTheInside]

Back on topic..
45u are you getting the bicyclemotorworks head and will you be able to make a "standardised" volume measurement for us by the methods Steve used please?
I am very interested in this head as Steve says it appears to have a shallower shape than the other aftermarket heads and a reasonable squish band going all the way out to bore edge along with decent cooling area.

 

[45u]

Back on topic..
45u are you getting the bicyclemotorworks head and will you be able to make a "standardised" volume measurement for us by the methods Steve used please?
I am very interested in this head as Steve says it appears to have a shallower shape than the other aftermarket heads and a reasonable squish band going all the way out to bore edge along with decent cooling area.

I all ready have one of those heads. I have talked to Mat I think is his name and I am sure his 6cc is correct. If I have time I will check the CC but I think I broke my brute. This will be going on my second build using the genuine Grubee 66cc engine. I have not done much other then research and collecting parts. The pictures I posted that Steve is talking about is the head I have.
This is the frame and front end I will be using.

 

[FurryOnTheInside]

Thanks, 45u. I think the interesting point made in the first post is the piston-in-contact measurements that Steve did show the flat plate measurement is not the whole story. Obviously one still has to add the volume of the squish area to all of these .. It certainly is a bit more complicated than 6cc is 6cc, 5 is 5, 7 is 7 etc.
Hopefully the manufacturers will be reading and will be able to standardise their measurement with piston in place and a reasonable assumed squish clearance. (But then, are all the pistons the same shape?)

 

[45u]

This is what they say on there site see below. I know I have talked to Matt on the phone but not about the head. I know where you are would be expensive to call him so you might want to try a email. Being the weekend is here might be Monday before you get a reply. When I called I left a message and Matt got back to me with in 2 hours.

{The head has a versatile 6cc volume compression chamber which works great with regular gas from the pump. Only the most advanced race engines that are heavily modified with bigger carburetors & super-high flow exhausts would need race fuel with this head.

Deck height of zero to .03″ for maximum compression. NOTE: GT-5 engines have a higher deck hight than most others. You will need to bring the deck height down to fully appreciate added power.}

 

[Philandra Chambliss]

Long time no talk to for the one at the bottom right how is the deck over a stock head i need the extra space