what does a spun bearing sound like... are there any symptoms to look for in a spun bearing? what numbers should i expect in a compression test?
what other diagnosis should i do to make sure my engine is in tip top shape? (prevention of future problems)

 

I don't know what a spun bearing sounds like, but probably not good

I think the numbers for a compression check should be around 230-250 for a healthy motor.

You can also do a leak down test and maybe a valve adjustment to make sure all of valves are adjusted properly to stock specs.

 

A spun bearing sounds like a monkey with a hammer banging on the inside of the motor. When the bearing spins it becomes loose and the rod flogs around on the crank. When it gets really loose the piston can hit the head as it goes over top dead centre.

A spun bearing is normally associated with a drop in oil pressures.

Best way to monitor ongoing engine wear is to see if the engine is making metal. Check the magnet on the drain plug for ferrous metal, and invest in a filter cutter so you can cut open the oil filter and stretch out the paper element for inspection. Wear gloves as sharp edges and slippery filters can bite.

The rings/valves can be checked with a leakdown tester which can show very slow leaks. A compression tester generally tells you if something is really wrong like a bent or burnt valve, or completely stuffed rings.

Good luck.

Speedracer.

 

so a spun bearing would show a drop in oil pressure?

 

What symptoms do you have and why do you think it happened?

Also what makes you think it is a spun bearing?

 

https://www.s2ki.com/forums/index.php?showtopic=221724

 

Your motor is fine. Don't even think twice about it.