031 flywheels - measured!

[a. palmer jr.]

Did you alter the timing when you switched over to electronic?

I did it for a few reasons. I like messing with stuff just to gain knowledge and experience and I think points suck compared to electronic ignition. When I switched my Ironhead Sporty to electronic ignition it ran smoother, started better, and had better power than it did with points. Finding an original Stihl condenser would be impossible and just getting access to the points is an ordeal on an 031 so hopefully I won't ever have to mess with it again. I'm going to put the module in the airbox so if it does go bad it's a 2 minute job to replace it.

That's exactly what I did on my 031, points in airbox. I removed the key and advanced the flywheel about 1.5" on the outside edge of the flywheel, remembering to mark the position in case it slips or needs removed again, put it back together and it runs just as good as the 031 I have that has points. No need to buy a different flywheel.
I tried not advancing the flywheel and it ran real doggy, no rpms at all and it seemed to run hot.

 

[a. palmer jr.]

I promised someone on AS that I would measure the difference between the 031 Points flywheel and the Electronic flywheel.

There are a couple of different styles of Electronic wheels but they are interchangeable. The version I'm showing here is that with the points covers, but if you look at the bottom left, it has a symbol that represent it as electronic.

I photographed the wheel "in plane" so there was no distortion, fed them in a background layer in Visio, and used the cad functions to perform the measurements. The leading edge of the N magnet was used as an index for measurements relative to to the key slot.

There has been a lot of AS discussion of whether you can just replace the points with a module whether you need to "reverse legs" on one, etc etc. I don't know the definitive answer, but if you get it wrong, even though the saw "runs", the timing is way off.

If I have time in the next few weeks, I'll runs some tests with points and different modules/flywheels, and use a timing light to show the results.



Points version:

Electronic version:

That's why I said that you need to remove the key and advance the flywheel. I think I advanced mine about an inch and a half measuring from the outer edge. No problems since then. I used the Nova II.

 

[a. palmer jr.]

I used the Nova II on my conversion..I did have to move the flywheel forward (CCW) 20 degrees and it worked fine. I didn't try reversing the wires. An electronic flywheel will work straight up. One thing I noticed about the 031 is that the carb has to be adjusted pretty good or it will miss at idle and part throttle, that was on my other 031 that hadn't been converted.