timing light

[Scamper]

[quote author=Klunky Chris link=board=14;threadid=13024;start=msg120473#msg120473 date=1079157150]
The problem with cruiser timing is that there are only 2 marks on the flywheel.[/quote]

I just mark the TDC bubble with some chalk, then use the advance dial to see what the timeing is. A lot easier than trying to interpolate between hard-to-see flywheel marks.

 

[hj60]

[quote author=red64toy link=board=14;threadid=13024;start=msg123735#msg123735 date=1079673762]
Dumb question but how do you set the timing with a vacuum guage? I thought you only used the vacuum guage for setting the carb?
[/quote]

It's not a dumb question.
With the vacuum advance disconnected and plugged (so you don't have a
vacuum leak), advance your dist until you get the highest vacuum reading, then turn back 2° - 3°. I haven't done a Cruiser this way, but I'd bet it ends
up withing 5° of the factory timing.
As a motor ages, its timing requirements change, and setting timing by the
mark isn't as accurate anymore. Vacuum is much more accurate.
It's also very good for setting up your carb.

 

[IDave]

Someone on the Pirate board said to turn it back 1 inch of mercury from peak vacuum. (for another perspective). Also, it varies some for elevation. I do that and then fine-tune by doing the "floor it going up a hill in 3rd (or 4th) and adjust so it just begins to ping but not too much" method.

 

[red66toy]

Thanks a lot guys for the great help, I just got my vacuum guage in the mail so I am going to try this method out on monday. I will let you guys know how it turns out.

 

[red66toy]

So if it is better to time the engine using a vacuum guage then why even bother with a timing light?

 

[hj60]

Cos the timing light gets you to where it'll run.