XS650 Ignition timing revisited - Are we too advanced?

[motorbikerx]

I found out the hard way that a timing light is crucial and correct timing is more important than just how it starts or sounds. View attachment 229852

By the look of your pic it's from overadvanced...I've retarded mine.
I have a good timing light but no mark on the rotor anymore.
I'll call the rewinder and see what could've happened.....

 

[5twins]

Yes, I understand you have no rotor mark. The year of the stator isn't real important. All you must know is if it's the '79 and older style or the '80 and later style. Which one it is will determine the type of regulator you require (power switching/regulating or ground switching/regulating).

 

[motorbikerx]

Yes, I understand you have no rotor mark. The year of the stator isn't real important. All you must know is if it's the '79 and older style or the '80 and later style. Which one it is will determine the type of regulator you require (power switching/regulating or ground switching/regulating).

Isn't that covered in my other thread?
With pics and descriptions....
Thought we came to the resolution that the bikes got the later regulator and that's one of the many causes of it not charging.
1 rotor was bad...rewind it
2 broken wires out of stator, Got a good one.
3. Wrong regulator
That's covered in the other thread...
I'll go back there to tell you'se how my footpegs just broke dumping both my feet on the ground, thankfully at very low speed at roadworks cos we were two up and couldve been badly hurt or worse if we were going faster I hate to think of the consequences.
A bit of bush ingenuity had me find a tree branch to jam wood to try to hold the pegs up...In reality once I got up into third gear it was far more comfy to have both feet up on the engine than forward controls

 

[AUTOMAN]

Higher octane fuels usually burn slower.(without any other changes)
Less power and high EGT's.(burned valve faces)

Higher octane is needed for higher compression engines for anti-knock protection.(without any other changes)

Cranking the timing advance up is similar to higher compression at certain RPM's.

Lower octane gasolines will tend to have 5% potential power increase if taken advantage of.

Check the octane ratings in F1 racing.

cliff

 

[Bumblebee]

By the look of your pic it's from overadvanced...I've retarded mine.
I have a good timing light but no mark on the rotor anymore.
I'll call the rewinder and see what could've happened.....

Yes mine was too far advanced. Ran great, started easy, burned holes, ha ha

 

[AUTOMAN]

Burned holes is PRE-ignition. Right dead over the plug.

It may start by hot spots or detonation which creates hot spots.

cliff

 

[zrx1100]

I was playing with the ignition advance on my modified motor: https://www.xs650.com/threads/sachse-ignition.65694/#post-828582

While tuning the exhaust, i took dyno measurements back to back with the stock 15/40 deg and 10/35 advance settings. Little difference. It does 'feel' to run better with the 10/35 degree advance.