Originally Posted by dannym

No, by ear is not OK.

You find your timing by setting the crank where you want it to be, normally 24 BTDC. Then you move your IP until it's in the correct spot. This can be done by using the A-B timing tool. Or there is a huge thread on using the Milli Volt method:
http://www.peachparts.com/shopforum/showthread.php?t=152389&highlight=millivolt

There is a IP holding tool that will lock the IP in place when the engine is precisely at 15° ATDC.

You advance the timing by moving the IP toward the engine and retard timing by moving the IP away from the engine.

Danny