Ignition Timing

mwoo · Feb 27, 2011

Hi all - a while back I posted a query regarding the acuracy of the 'inbuilt' timing scale inside the primary chaincase on Commandos. I decided to recheck the timing on my 920 using a dial guage etc. I retimed the ignition (Tri-Spark) based on my 'findings' - result - first time staring every time hot or cold (the first start was after standing for five months) - the bike runs better than it ever has --. I checked the timing based on the inbuilt scale and found that it was 4 degress out. This goes to show that I've been timing the bike incorrectly ever since I've had the bike (22 years).

Hobot · Feb 28, 2011

Beware, unless a degree wheel put on Crank to know for sure what you are reading.

mwoo · Feb 28, 2011

Yes - I did use an accurate timing disc - -

Carbonfibre · Feb 28, 2011

mwoo said:
Hi all - a while back I posted a query regarding the acuracy of the 'inbuilt' timing scale inside the primary chaincase on Commandos. I decided to recheck the timing on my 920 using a dial guage etc. I retimed the ignition (Tri-Spark) based on my 'findings' - result - first time staring every time hot or cold (the first start was after standing for five months) - the bike runs better than it ever has --. I checked the timing based on the inbuilt scale and found that it was 4 degress out. This goes to show that I've been timing the bike incorrectly ever since I've had the bike (22 years).

By far the most accurate way to check timing is to establish TDC position, through the use of a stop, mark the rotor, and then time using a digital timing light with advance/retard function.

pete.v · Feb 28, 2011

Carbonfibre said:
mwoo said:

Hi all - a while back I posted a query regarding the acuracy of the 'inbuilt' timing scale inside the primary chaincase on Commandos. I decided to recheck the timing on my 920 using a dial guage etc. I retimed the ignition (Tri-Spark) based on my 'findings' - result - first time staring every time hot or cold (the first start was after standing for five months) - the bike runs better than it ever has --. I checked the timing based on the inbuilt scale and found that it was 4 degress out. This goes to show that I've been timing the bike incorrectly ever since I've had the bike (22 years).

Click to expand...

By far the most accurate way to check timing is to establish TDC position, through the use of a stop, mark the rotor, and then time using a digital timing light with advance/retard function.

I agree with you, CF. A dial indicator can easily misslead by a degree or 2 on both sides of rotation leaving you 2 to 4 degrees off on the scale.

Ignition Timing

mwoo

Hobot

mwoo

Carbonfibre

pete.v