1917 Powerplus twin ignition timing

[slamiste]

Hi,

I'm installing a new mag on my 1917 PowerPlus. I can't use the "line up the marks on the gears" method because my mag gear has mutiple, professionally enough looking marks to make me doubt which is the correct mark. Can someone propose an alternate method (distance from TDC on front cylinder for points just opening) or .....?

I'm installing a Morris Mag and doubt the gear key / points relationship is to old time standards.

[slamiste]

Hi again,

I'm a bit new to this forum idea so maybe I've violated some forum friendly rules. So, let me introduce myself.
My name is Steve Slaminko. I've been an AMCA since 1986. Since I'm still working, the only national meets that I routinely go to are Wauseon and Davenport. My children have been involved in AMCA since they were very young and are now all full members. My youngest son and his wife (Jake and Tara Slaminko) organize the field games at Wausoen. Between my 2 sons and I we probably have over 50 antique motorcycles. Jake is into Europeaon bikes (Guzzis, Ariels, Triumps as well as American iron and is currently retoring a 1957 Ariel Square Four. My oldest son Eli is into Japanese and European bikes and has a large stable of them as well as a 1947 Big Twin Flathead. I"ve got a pretty big collection of American bikes dating from 1917 (the subject of my original question) up to a 1957 FLH. As I'm getting up there in age I've also got two BMW Air Heads and a Guzzi T3. Many of you may know me and my family and I'd love hearing from you. As far as the original question goes I've been told from other sources the timing should be set at +/- 3/8" before top dead center on the front cylinder. If any of you have anyc omments on that I'd like to hear them. FYI - If you were at Wauseon in 2009 - 2010 I had the PowerPlus there and running so maybe some of you remember it. It's unrestored although not original paint and is very complete.

[painterdale]

Hi, Steve! I don't believe you violated any rules except not posting a picture! I'd like to say "welcome" but you've been here a lot longer than I have. Sorry I can't help with the timing question. Dale

[gharper]

Steve,

I would go 3/8" or more BTDC, but not less. I set my 24 chief and 19 X at 7/16" BTDC and they do very well. My reasoning is that I tend to run them a bit faster than back in the day, we have much better fuel available now, I'm at 5280' altitude and ride into the mountains, plus the biggie is you have an infinitely variable spark control, so you can adjust it as needed to dial it in for every engine speed and load. I think the manual spark control is a big deal, and often overlooked when riding these old bikes, especially when dragging a sidecar.

Remember, when setting the timing,it is imperative that you set the timing to BOTH cylinders. If you just set it to one, you may actually be off by a considerable amount on the other. It's not uncommon for guys to inadvertently set the front cylinder to fire on the rear points lobe, then the rear cylinder isn't even near the ball park, let alone in it! This is best done with the tank off, top cylinder plugs removed and lots of patience. Set one, then check the other. You may be surprised how far off it is. Dialing it in may require moving the mag gear a notch, or dressing the lobe of the cam in the mag that is firing too early, bringing it in to the correct place. Lots of time and patience along with careful measuring is required. When you get it right, the engine will start easier, idle incredibly slow and smooth with the spark retarded and give great top end performance. It's one of the old racer's tricks!

Good Luck! Gene

[slamiste]

Thanks Gene and Dale. It nice to hear from both of you.

Gene - Thanks for your detailed information. I'm probably a couple of weeks away from setting the timing and I'll let you know how it works out.

Dale - Sadly I don't know how to post a picture. I don't tweet, facebook or any of that other modern stuff but I will post a pictire of the bike once one of my children show me how to do it.