Hi Folks. My dad has a BSA M20.He is wondering if he should convert it to electronic ignition? If so what would you folks recommend? He's, had a couple of magnetos and both have given trouble.Any help would be much appreciated. Thank you.
email (option): mspruhan73@yahoo.com
A properly rebuilt magneto will still give reliable service...I've yet to fit an electronic ignition to any of my mag equipped bikes as I've never felt I needed to...There are some 'self generating' electronic ignitions that have a casting that looks like a mag and onto which the dynamo will fit (BTH for example..)and that is what I'd go for if I was to fit one...
However, they are expensive (more than the cost of a mag rebuild) and you are then tied to that one supplier and thus reliant on the quality of their development work, component specification and after sales service...
Personally, I wouldn't even consider any other electronic ignition that does not generate its own power...To tie the ignition to the dynamo/regulator system would be madness IMO as that is the least reliable part of the electrical system in my experience...
One advantage of electronic ignition is a 'proper' advance and retard curve courtesy of the electronics and also a strong spark at starting speeds, though as stated, that's not an issue with a magneto that is functioning correctly....
No doubt there will be a contributor who might not agree with the statements above and as usual, it's case of making your own decision ultimately..As in all things both systems have advantages and drawbacks...Ian
email (option): ian@wright52.plus.com
For what is worth here is my experience of altenative ignition systems. I don't know haw much it will help with your decision makingthough!
I fitted a modern BTH electronic ignition to my A10 20 years ago and haven't had to do anything with the ignition system since (I should probably treat it to new plugs one day!). It transformed the starting and running of the bike. It was expensive but so was having the mag rebuilt every 2 years by yet another 'expert' who slagged off the prevoous re-builder. Its more than paid for itself now.
I have had a Boyer on the other A10 for over 15 years and once I'd sorted out the charging system its been very reliable.
When I restored the M20 4 years ago I decided to try staying with a standard mag and had that rebuilt. Apart from having to maintain the points the only other hassle used to be condensers failing and this is largely a thing of the past with modern condensers. I've done nearly 7000 miles on the mag so far with no problem.
I don't think there is a right answer to this question.
I've fitted Thorspark ignitions (https://www.sussexmotorcycles.com/thorspark.html) to several mag bikes including a couple M20s. They work very very well once timed but as Ian points out they rely on the dyno being in reasonable shape. The Thorspark is basically a solid state points replacement and fits into the mag in place of the regular points. The magneto and dyno remain outwardly unchanged. Spark is provided through a coil hidden somewhere suitable and the whole show is more or less hidden from view. the advance works as it always did so there is no advance curve advantage but then again, there is no "black box" to fail.
On the plus side, timing is now infinitely adjustable and can be set with a strobe off the engine sprocket. There is no "slop" in the timing arrangement so the spark is more consistently correct from cycle to cycle. Timing becomes a once-and-done thing. The coil uses about 1/4 amp so with a fully charged battery would theoretically run all day (and the next) without a charge. With LED lighting, a charged battery should give you spark and all lights on for 4-8 hours riding.
On the minus side, a bad dyno could leave one stranded if the rider does not take this into account in their pre-ride checks. The wiring system needs to be in good shape including a secure earth strap from battery to frame. If the battery becomes depleted, it can be problematic finding a 6 volt charger when away from home. Some riders buy a bit of insurance by having 2 5ah sealed batteries and having the ability to switch between them (like a reserve on a gas tank). For peace of mind, a rebuilt dyno would be advisable.
Balanced and objective comparisons on the merits of each system are rare as it seems to be a divisive issue and many riders find it difficult to separate technical comparisons with emotions or nostalgia. At the end of the day it is a personal choice. Both systems provide the spark one needs to go wheezing through the countryside on an 80 year old machine. Ultimately, both systems, when working properly, are very reliable and equally unlikely to fail in use. My preference is for the electronic option but the important thing for me is that whatever system I have, I get to ride my motorcycle.
email (option): cas.vanderwoude@gmail.com
I live in a country with compulsory daytime headlights...a rule that I regularly ignore, but there are times when I forget to turn the lights off...Unless the lights are switched via the ignition, there are inevitably flat-battery incidents. With a magneto, this is no problem whatsover...
I'm not anti-electronic. I'd always fit it on a coil ignition machine, but MO1s are just so nice and reliable once they're sorted and completely self-contained so simpler wiring too...
Like Rik I've had and still get good service from magnetos..I've never broken down out on the road in more than 40 years with a mag related problem apart from an M21 that didn't make it home from the chap I bought it off and back in the 70's on some bikes that had never had the mag rebuilt from new!!...
I'll use what functions well generally and so far the mags have been OK on my older bikes...Like any reconditioned unit though, they are only as good as the chap that does them... I don't have any problems with the concept of electronic systems...For example, that was the best choice for my Rocket 3 and fitting one vastly improved that particular bike...One of these days no doubt, I'll give a BTH or similar a try. Currently I'm working on a very non standard 640cc B33 project so that might be the one!!...
Whilst on the subject generally....Any comments, observations, experiences from people that have used Alton or similar alternators to replace the dynamo on a magdyno equipped BSA single?....Ian
email (option): ian@wright52.plus.com
I too am a big believer in running magnetos. I have 12 bikes with mags and never have any problems. Most have never been rewound and still have the original condensers. I have a friend who fitted a BTH electronic ignition to his Velocette and it has been nothing but problems. He eventually put the magneto back on.
As for Alton alternators, I have run one and it died after a couple thousand miles. I have heard of a number of other bikes having the same problems. There are others out there that like them, but not me!
Talking to a distributor here in the USA who used to sell them and won't any more do to Alton always blaming the owner of the bike for any problems and not honoring the warranty. What I have been told is, the Alton will make 150 watts for a short period of time but is only rated for 90 watts continuous. If this is exceeded (battery almost flat and lights are turned on) and you get up to speed so the alternator is at full output, it will overheat and burn up.
Here is another opinion of Alton.
http://www.petersclassicbikeparts.nl/contents/en-us/d558_ALTON.html
I am sticking with my Lucas generators which give me no problems.
I got my maggy rebuilt in 1992
The bike is now pushing 200,000 miles and to my astonishment is still running the points that Peter Scott put in there .
So I am more than happy as all I really have needed to do was pop out the wick & reoil it from time to time.
The dynamo has been rebuilt twice in that time and is once again non functional .
Once you go kettering you are totally dependent upon the battery & dynamo to get you home
Now in the UK where it is only a days ride coas to coast that might not be a problem but down here it is a big problem.
Got a friend with EI in his A 10 that regularly dose trips of 1000 to 2000 miles
He keeps a spare Cyclon in his saddle bags just in case the battery / dynamo fails
He has an LED stop ;tail & parking lamps and with them on there is 30 hours of run time so if the worst happens he can join the 2 batteries together and get one ( or both recharged overnight as few service stations / workshops have 6 v chargers ony more .
Thanks Bruce...Not encouraging then...I've heard negative reports on the Alton previously..Any info. on the German produced unit?...Ian
email (option): ian@wright52.plus.com
The only problem I've had with the Alton in 15 years use (on an A10) was due to a slipping belt which was fixed by fitting a toothed belt. Early ones were a pain as you had to fit a switch to prevent battery discharge through the alton when the engine wasn't running but this is not necessary on later models.
I recently wanted to make the Super Rocket electric more suitable for touring but decided to take a different route and converted to 12v using a DVR2 and led lights all round so plenty fo capacity to run sat nav, charge phone etc. Working well so far.
(With leds you don't even need a dynamo really)