advance springs

[nmainehunter]

I have a 65 up timer with the advance weights and I have a few sets of springs and they are all different. Is there a way to determine what machine they were made for. Was there a set made that was better than the others? Tricks of the trade! Thanks,Ron

[Deye76]

Without any identification will be hard to tell what strength springs you have and at what RPM it gets to full advance.  Stronger springs will cause the timing to advance slower, weaker springs will cause it to advance faster.  A trial and error process unless you have access to a dynamometer. If you hear the engine knocking (pinging), the advance is too fast and you would need to install the stronger springs. Once dialed in be sure to keep the springs greased lightly so you don't have to replace and figure out what the engine likes. 

[Excalibur]

You can use a strobe light to see exactly what advance profile you have. A rev counter would be good to really identify the rpm point of full advance.

BTW, I transfered the timing marks to the front sprocket for easier strobe timing. There's nothing like seeing it. Then you can know how it's behaving, condition of timer bushings etc.
Can put a pic up if you want..

[Dave_R]

I have this exact same timer on my '53. I works just OK. The whole idea was to replace the need to manually advance (origional older timers with the twist-grip advance) with an automatic one. With this, the idea was to have a very weak spring so that it is advanced for kicking, but once started it finds its "spot" for running. That is, once the RPMs are faster than you can kick, it basically goes full retard to the "run" position.

This eliminates the need for the "twist grip, cable, etc.

For static timing, I usualy hold the weights to "full out" position, then time by the flywheel marks per the manual. Then, release the weights, and it is basically in the "kick" position for starting.

Bottom line is that the weaker the spring that still moves the weights, the better (I found).  Otherwise it idles horribly because the timing moves at these low RPMs.

I know some guys (and myself) tried to put the "cone" engines points springs in which are stiffer, but can never get them to run right.  Unfortunately, i have found out that getting the origional springs intended for this particulat timer is very hard to find.  Most aftermarket ones claim to cover aplications for this timer and the "cones" with one spring, but Finding the origional springs that are weaker is a challenge.

Anyways, just my experience with these timers.  Not meant to undermine if you are trying to actually have a running advance curve dialed in, which these timers are really not meant to do.

- Dave

[Deye76]

If the bike will be used, I don't care to worry about being all original, and IME an electronic distributor worked excellent. You will however need a 12 volt system.

[JSD]

In my geny shovel I fitted reverse drive gears so disy spins anticlockwise and run a cone module in a A557 Acell