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Over the summer I rebuilt a cb400tii engine, and am now getting ready to fire it up for the first time. However, over the last few days I have begun to wonder whether I used enough assembly lube, particularly on the pistons/cylinders, and now am having doubts as to whether I need to go back and make sure that it is well lubricated enough. I am wondering, though, if anyone could tell me whether there is a way to prime the engine with oil prior to firing it up so that in the event that enough assembly oil wasn't used, it won't burn up? Would spraying the cylinders with fogging oil do enough good? Or should I just plan on spending a weekend rebuilding the top end again?

Fingers crossed!
 

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Sounds like it's more likely you used too much. Many veteran engine builders put the pistons in dry but it's a subject that can bring out a lot of opinions. Enough assembly lube to coat the bearing surfaces is all you need there, excess is just going to drip off anyway. On your engine it's important to fill the valleys below the camshaft with oil before installing the valve cover.

Otherwise just ensure the engine is filled to the proper level with an approved motorcycle oil, please don't ask which is the best one, just browse any of the engine sections for a while and you'll find boatloads of recommendations.
 

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New engine, old engine, after oil change; I leave the ignition off and crank the engine over a few revolutions, pause and repeat until the oil pressure light goes out. Then I will start the engine.
Since you did oil the pistons/cylinders I would be sure to have at least one extra set of new plugs handy. Once fouled they are throw aways.
 

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I NEVER put pistons in dry, always well oiled, piston skirts and rings both. Once the cylinder is installed I turn the engine over repeatedly while wiping the top of the cylinder out with a clean cloth. I keep doing that until the top ring no longer brings up any more oil to wipe away. That oil, pushed up to the top of the cylinder, will also contain all the dirt and grit on the cylinder wall that you missed while cleaning up the cylinder.
Used that method for years, on everything from Honda 50s to Caterpillar truck engines, and never had a problem with rings seating.
 
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