Alan F.
Veteran Member
A question to those that might know, are these inter changeable? It appears so but I'd rather hear it from someone more qualified.
The CA77 was also a 180 degree engine, single carb, one set of points.
CB77 was a 360 degree engine, two carbs and 2 sets of points.
So there are the crank differences as well. There must have been quite a few custom built 305s trying to keep up with the 450s.
Looking at the pictures of the 2 different pistons there's obvious differences in the dome. I suspect the CA piston will have a higher compression ratio.
My suspicion was that the Dream would have the lower compression ratio (single carb, touring intent), so the pictures may well have been incorrect or there's a significant difference in combustion chamber size on the Dream head (which seems less likely)
I've looked all over that mess and can't even find it, so many links either don't work or are in partial disarray. It's a shame too because we know there's a lot of info there
I would like a 305 dream with CB/CL 305 pistons ;I wonder if the CB/CL cylinder head(dual carbs,cam,points,etc.) would swap over,then possibly hook-up the top motor mount to the head differently?
Won't fit without major body surgery. Dream lower end has different gearing too.
In 1965 Honda reduced the compression ratios to 8.5:1 for CB/CLs. There are three different pistons for CB/CL72s in different compression ratios. Just two for 305s.