Re: 74 CB750 ENGINE REBUILD...
Posted by
Lucky 1 on
Oct 10, 2011; 10:27pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/74-CB750-ENGINE-REBUILD-tp3397907p3411028.html
"Piston rings did'nt look bad."
You must replace the piston rings of you take the engine apart.
If you just hone the cylinders and put in the old piston rings it will never be 100%.
The piston ring edges and the piston groove edges get worn and can leak compression.
Piston rings may look good but have worn and conformed to the the shape of the cylinder that they were in.
Some top piston rings have a moly insert in the ring that helps to break in the piston. That gets worn away.
On a Roadstar Adventure.