[A motorcycle nut]

 

[bilbikek411]

Nice,clear video.

 

[mike in idaho]

The spark advance unit can be accessed under the cover on the opposite side of the head. Blocking the advance weights open with a bent piece of welding rod enables you set the timing in the full-advanced position.

 

[motormike450]

If the XS is go'n to be a keeper... toss the points and the advance units... and pop for a Boyer.. yes, pricey... but once install'd.. ck system once a year.. done... better starts and performer.

 

[mike in idaho]

Before you spring for a Boyer setup, give this a read: $19 Junkyard electronic ignition | Welcome to the XS-650 Garage USA . I put one of these setups together on My XS650, started & idled great, pulled like train. The Boyer needs to have a full 12 volts to behave properly and full advance doesn't occur until about 5000 rpm. The GM HEI ignition module makes reliable sparks down around 9 volts and the stock advance curve gives the bike a little more mid-range grunt .
You can also run the GM module with points, using the circuit described here: http://www.geocities.ws/loudgpz/GPZheiModForPoints.html