How To Do 'camshaft Timing' Service Item On A Water-cooled Twin?

You have to measure the cam timing events to know if it was designed with advance built in. You need a dial indicator and a degree wheel. A "straight-up" cam (no advance or retard) has symmetrical valve timing relative to TDC so intake and exhaust timing events have equal but opposite angles relative to TDC.

Here's an example using my Yamaha XV950 stock cam specs that have 5° advance. With no advance, both cams would have exactly the same event angles:

Intake Valve Timing:
Open BTDC 26°
Close ABDC 46°

Exhaust Valve Timing:
Open BBDC 56°
Close ATDC 16°

Event Angle: (Lobe Center) IN 100° / EX 110°

...and with advance removed, there's perfect symmetry:

Intake Valve Timing:
Open BTDC 21°
Close ABDC 51°

Exhaust Valve Timing:
Open BBDC 51°
Close ATDC 21°

Event Angle: (Lobe Center) IN 105° / EX 105°

 

......he he!.....just kidding. A good job done and the BIG plus with working on the bike yourself is you know it's been done!