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Hello from NC

Mega325

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Coats nc
New to the forum. Just picked up a rigid with a cb750 engine. Time to learn about Honda bike engines. Any wisdom will be appreciated.
Thank you.
 
Run and set the valves-the most common error and it burns the valves up. The motors are odd in that the crap heat treat allow for more valve recession than normal and commonly the valves close up rather than the normal getting looser like most engines do.

Because you have to have shims nobody including the shops ever set them correctly. You need to set at .005" instead of the service manual spec of .003", the setting then lasts literally years longer and no bad effect at all from being slightly too loose.

A compression reading will tell the tale there; many being down on it because valves are too tight. The problem is that the numbers you get while setting the valves are not real, you have an invisible extra .002" of tightness that you cannot see in there and why you move out to .005" to get a real world .003" when running. Yeah, I know, you just have to trust me on this one. BTDT more than once and the burned valves to prove it.

Set at .003" the valves can close up almost instantly, I burned several on a brand new bike in under 5K miles.

Set at .005" the setting lasts up to 25K miles if done carefully. It's that last .002" that kills you.
 
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