Converting An Atlas To Electronic Ignition

Hello Jim, you shouldn't need to weld-up the auto advance mechanism as, if you fit one of the 'better' EI systems they are supplied with a new housing that fits where the old magneto was located. The advance/retard function is electronically controlled. i.e. you can throw the old mag away.

I can't speak for others but certainly mine (RITA) is chain driven and re-uses the original sprocket. The usual suppliers stock plain sprockets, although I lockwired mine on full advance (bob weights outwards) and put the springs safely in my Norton technical box in case I replace the mag.

Don't do as I did for a while and rely on letting it spin outwards when you kick start. It's hard to be sure, but it seemed to cause random starting problems.

It might not be easy to find somewhere to wire it. I should have bought a new plain sprocket. It's a shame  to ruin an auto advance one. New ones are hard to come by and are very costly.

I have two bikes with electronic ignition. The first is a 1960 Triumph TR6C, I installed a Thor Spark ignition on it while completing a engine rebuild. It uses the original mag housing and auto advance so looks absolutely stock to the original bike. The bike runs perfectly and has given no trouble in just over 2000 miles so far this year. The advantages to the Thor Spark is - looks original, -less than £200.00 to have up and running, - reliable to this point and easy starting, one kick usually hot or cold.

The second bike is a 1967 Norton 650SS. Have just completed an engine overhaul on it so have had an opportunity to reset the Boyers electronic ignition system on it, the mushroom unit is made by Classic solutions. I followed the instructions supplied by the Boyer (this system was on the bike when I bought it otherwise I would have installed a Thor spark system). The bike started first kick and I strobed it to check the full advance, previous owner had installed a rotor pointer and marked the rotor (I did check these with a timing disc for their  accuracy prior)  Watched  the advance come in with RPM,  I wanted 32 degrees all in and it was exactly that so did not have to re adjust. The advantage to this system is - no auxiliary advance system required as it is supplied electronically , -Boyer and Classic Solutions are well supported in the bike industry. The Norton also runs very well and is a one kick starter hot or cold.

Hope this helps, happy to answer any questions you may have if I'm able

The Thor spark uses the original Mag body and the original mechanical Auto advance.

IF you change to Pazon, Boyer, RITA, or Trispark, then the advance is built in to the electronic and you DO NOT need the mechanical advance. You buy and fit a plain (manual advance) sprocket, as mentioned above. Any idea of welding the mechanical auto advance is NOT to be encouraged.

Hi Jim,

I got the whole lot - Mushroom, Boyer, Sprocket etc from Norvil. That was over 20 years ago mind. I'm sure that the 'usual' suppliers will be able to supply all the bits you need.

Me? I have Boyer and fixed socket on my 650 and couldn't be happier. No adjustment since fitting it 20 years ago.

Don't forget that you will be able to sell your auto advance unit and your mag to others, making the electronic route even cheaper. Non sparking but complete mags go for silly money nowadays.

Regards,

George

I just bought a solid sprocket from RGM, slightly over £30, very prompt delivery too. It replaces a badly butchered and welded up way out of line,  ATD. The bike has a manual adv/ret mag, if I have to replace it, an electronic system will take its' place with the sprocket ready and waiting. 

Bear in mind mags are taper shaft and some electronics, I believe, are straight shaft.  ( a Lucas Rita I had was straight shaft )

Regards all, Terry

Just to be clear, I mounted the Thorspark pickup in place of the mag points assembly in the mag. The mag still has the original mechanical advance system intact and functional. The HT leads still come out of the mag but serve no purpose other than to maintain original appearance.The coil assembly is mounted under the tank out of sight . The bike starts and idles perfectly as well as rides down the road, very pleased with the out come and very inexpensive to do compared to mag rebuild or the electronic ignition system I have on the Norton. Will pm you a couple of YouTube videos of both bikes running if you like.

I love the Electrex replacement for the alternator/mag/rectifier/points/regulator.whatever.

Simple to set up, electronic advance. You need led bulbs though, as the alternator output is low.

The mag can be left in situ looking original

here i am  late to the thread, happy to have found it. the BTH electronic magneto? has caught my eye. Im not certain just what it is , replaces the old magneto and requires a plain timing sprocket or a lock up to the auto advance . has anyone knowledge of these? they are shown on the Alton starter website. Is this a modern version of a magneto? generates its own power for the igniton, uses coils and a box...  The thorspark system fits into a K2F or K2FC? I have an empty distributor housing and a very old boyer set up driven by inside another  Dominator dizzy body . The BTH is very impressive although not an inexpensive fix.