Thorspark

[Mark B]

The condenser/capacitor in the magdyno on my 1953 B31 is breaking down and it's been suggested that this is a good time to fit a Thorspark electronic ignition. Any thoughts from anyone who's done this (for or against)?

Thanks, Mark. 

[STAR TWIN]

Is a 6v dynamo the ideal charging setup for electronic ignition? A magneto overhaul will last 25 years +. I would suggest just biting the bullet and getting the mag fixed.

[JulianS]

I though about going to coil ignition on my A10 but always stall when considering the space to fit the coil, the extra wiring and becoming dependent on the battery for sparks and whether there would be enough current to power sparks and lights.

So I stick to my trusty K2F.

[Bles31]

Sorry for delayed response. I fitted a Thorspark to my 6volt B31 - it was pretty straightforward and gives a nice juicy spark. Bike starts second kick. The bike is part rebuilt so I haven't done any miles with the kit fitted. My ammeter is showing a healthy charge with the Thorspark in use, so it looks good at least for daylight use. I expect it will be OK at night as I can put on the headlamp and still show a charge. You will obviously be dependent on the battery but I'm OK with that. Get your dynamo in good nick! One thing I need to investigate is the use of a pack of AA cells as a back up should the battery go flat - some people do this apparently but I don't know what range this would give (obviously not great if lights are needed). If it looks OK a pocket full of AA's will be travelling  with me!
You will have some extra wiring to hide away - it is bright green and red. I have bought in some more subdued colours to fit when I get time. There will be a coil to mount and hide. Mine is under my single saddle - pretty well sheltered but needs careful positioning to avoid debilitating shocks!
It's really all about whether you are OK relying on your battery.
Hope this helps.

[Mark B]

Thanks for the responses. I've had good reports from others so I've gone ahead and bought the kit. And thanks for the comments Bles, the wires are rather garish, and the next thing is to decide where to put the coil.  Did you have to make up a bracket to fit it under the seat?

[Bles31]

Two photos attached. Still not entirely sure about clearance above coil. Toolbox is another possible position, but require very long ht lead.

[Mark B]

Thanks for that.  I've got a big voltage regulator where you've mounted the coil.  Looking over the bike yesterday the neatest solution seems to be inside the toolbox.

[WayneBergman]

Mark have you got the Thorspark up and running? I am thinking of going this route as well. I am light in body weight and have a hard time turning the motor over fast enough at start up, even with full retard I normally have to run with the bike and bump start. If I get stuck on our local ferry system I may have to wait until high tide to roll off the boat.
My 52 B33 is currently running mag/dyno with 6 volt positive ground. I realize Thorspark sells these units to match both voltages but I am kind of thinking running the unit as a seperate unit powered off of my 12v rechargable lithium battery from my cordless drill. It is a 2ah pack so should keep thet bike running for 8 hours no problem according to manufacturers amp draw specs. I also have two of these pack and they are very tiny. I was thinking of tucking the coil and one of the lithium packs in my little saddle bags shown below. This way I can run a 12volt horn or what ever off of the pack as well. Any thoughts or feedback much appreciated, I have not heard much about this system until I stumbled onto it through this post. Sounds like a good deal for around 200 bucks and leaves the bike looking some what stock with the ability to still use  my manual advance lever at the handle bars.....thanks wayne