The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: Housewiz on 10.12. 2012 02:33

Title: Is electronic ignition the way to go?
Post by: Housewiz on 10.12. 2012 02:33
I found a website that discusses the inconsistent operation of Lucas magnetos when they get hot.  Is it true some bikes won't start/run when the mag gets a bit too warm?

My SR came with a mag missing lots of parts so off to eBay I went and bought rebuilt mag.  Nothing unusual there except the seller sent it to Japan and the Japanese guy's rocker box cover to me.  Would the consensus be to get a refund on the eBay mag and upgrade to an electronic ignition?  I am shooting for a dependable bike here.

Thanks,

Steve

Title: Re: Is electronic ignition the way to go?
Post by: Brian on 10.12. 2012 03:14
Your going to get a lot of varied replies to this one Steve, with all sorts of recomendations and theories.

Personally I like magneto's. If you have a magneto that has been reconditioned by a competent expert your bike will start easily hot or cold or anywhere in between and you should not have to touch it again for many years.

Electronic units can have some advantages with electronic advance curves but the problem is they are externally powered. You need a battery and that has to be kept charged by a generater. Some will argue that modern bikes all have electronic ignition which they do, but they also have high output modern alternaters. They dont rely on a 60 year old generater.

With a electronic system if you forget and leave your lights on or have a wiring fault, then you walk home.

Another problem with electronic systems is the voltage required to make them work, now a lot will disagree with me here and say that they will start the bike with only 2 or 3 volts left in the battery. In my experience once the battery drops under 6 volts the bike will not start regardless of what the manufacturer claims.

There is another unit available, a BTH system that is self generating like a magneto. The best I can describe these is a modern version of a magneto. They are fully electronic and seem to work well however I have doubts about the quality of the electronic components used, I recently had to repair one of these units, it needed a new CDI unit.

For those that say magneto's are old fashioned and no longer needed then consider this. All modern piston powered aircraft still use magneto's. Electronic systems are not considered reliable enough for the aircraft industry.
Title: Re: Is electronic ignition the way to go?
Post by: Housewiz on 10.12. 2012 03:32
Hey Brian,

Excellent reply!!

Let's hope that wayward mag makes it home from Japan.  It was supposed to be totally rebuilt and tested and I really don't need another rocker cover that's worth a 5th of the mag.

Thanks,

Steve

Title: Re: Is electronic ignition the way to go?
Post by: Rocket Racer on 10.12. 2012 03:49
I hope your mag turns up and is as described.
A decent mag is a sound investment. Sadly a bad mag (even a badly reconditioned one) is a liability.
I've run points ignition (on an atlas), lucas mags, a modern BT-H and a modern Joe Hunt on my A10 and B33.
All could provide reasonable reliability and all could and have caused infrequent problems.
Most mags dont like rain, but neither will a points set up. They should all also get you home.
The big catch with "old" mags is that they can have a myriad of little issues that can be rather testing  *eek*

Good luck
Tim
Title: Re: Is electronic ignition the way to go?
Post by: stu.andrews on 10.12. 2012 09:12
I go along with what Brian says. I've had electronic (Boyer) & magnetos. Any fault with an electronic system & your bike is immobile whereas you'll nearly always get home with a magneto. If a mag has been professionally rebuilt, then that's the way I would go. Like Brian has rightly stated, aircraft use magnetos:- there's no room for failures up there!
Title: Re: Is electronic ignition the way to go?
Post by: warmshed on 10.12. 2012 09:45
It depends on you way of thinking.

 I believe electronic ignition is the way to go. Just look at all the cars on the road, most have electronic ignition. zero have mags (maybe a few veterans) and only older classic cars have contact breakers and most of those have electronic conversions. How many do you see broken down at the side of the road with failed spark?
I have had a Lucas rita on my Velocette for 30 years and you get full high intensity spark even if you kick over slowly, does not get weaker when hot. Majority of classic bikes that are difficult to start can trace it down to a mag.

New electronic ignitions  can be cheap and are reliable, newer ones less than £20 such as http://www.ebay.co.uk/itm/Powerspark-45D-ELECTRONIC-IGNITION-KIT-for-Lucas-43D-45D-59D-Distributors-/360508264952?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item53eff791f8 so viable to carry a spare.  The expensive part is the mechanical magneto replacement, but I bought a complete lucas RITA replacement  A10 kit on ebay for £80, so they are available without paying £200+,  there is one at £60 on ebay at the moment with single spark but easy and cheap to change to twin. http://www.ebay.co.uk/itm/Lucas-Magneto-replacement-electronic-ignition-kit-Triumph-BSA-Norton-Vincent-/330842117269?pt=UK_Motorcycle_Parts&hash=item4d07ba1495

The downside as mentioned is the need for reliable electrics. Well if you don't have a working dynamo or alternator, lights etc  then maybe you should not be using your bike anyway? If you have the later alternator instead of a dynamo then you can normally get a good spark with a flat battery on kick over, I can on my Velo with alternator conversion.

Magnetos have been around for a long time and many find they work well. Later capacitors increase reliability but don't forget the old 60 year old bearings, flaky points and brushes.  If you are half way round the continent and the mag fails??? .

Originality is important to some people, I think the mag replacement points holder looks right (was fitted as standard to some British bike when mags dried up in  1969-70, Velo Thuxton being one.) But I want reliability and consistent high intensity spark and good starting so my Lucas competion magneto will stay on the garage shelf .
Title: Re: Is electronic ignition the way to go?
Post by: Beezageezauk on 10.12. 2012 09:54
Hi Steve,

I'm also with Brian all the way.

My A10 is still running on 6volt electrics with magneto and I travel several thousands of miles on it each year with most of my journeys heading to camping weekends and bike rallies.  I've noticed over the years that if a bike won't start up at one of these events it's invariably because it is fitted with electronic ignition and the battery is not powerful enough to allow the engine to fire up.  Because there is enough power in the battery to work the lights most owners think that the battery is ok and it takes a long time for them to realise that the battery needs to be well charged for the electronic unit to work.  Most guys I know who travel to these events (and have electronic ignition) now carry jump leads with them.  

As has been mentioned.  Electronic ignition is a modern(ish) thing but the rest of the bike needs to be updated to more modern equipment for it to be reliable.



Beezageezauk.

Title: Re: Is electronic ignition the way to go?
Post by: LJ. on 10.12. 2012 09:59
Magnetos for me... a classic part for a classic bike. They take such little maintenance and don't rely on anything else for their running. Good quality brushes are important though, the worse scenario is soft brushes with lots of carbon dust around the slip ring, but if you regularly clean it out then even soft brushes are not such a problem.
Title: Re: Is electronic ignition the way to go?
Post by: cyclobutch on 10.12. 2012 10:36
6V and magneto for me. I was fortunate that mine came with a complete mag, though I did have that refurbed whilst I was doing everything else. I'd only go electronic if it made sense financially.

Title: Re: Is electronic ignition the way to go?
Post by: Brian on 10.12. 2012 11:08
I was going to put this in another topic but seeing as we are on the subject I'll stick it in here.

A few weeks ago I had a Triton bought to me with an ignition fault. Its basically a Triumph Bonneville motor in a wideline Norton frame. None of that really matters but it was fitted with a "modern" BTH ignition system. Most have probably come across them but if not they are a modern version of a magneto, self generating (no external power source required) and fully electronic.

The bike would start and run fine cold but as soon as it warmed up it lost spark to one cylinder (right side), I quickly eliminated the HT coils as being faulty by simply swapping them over. After contacting the manufacturer his advice was that it would almost certainly be a CDI unit so he sent a replacement. I fitted the replacement CDI and it cured the problem.

In the attached photos you will be able to see the two CDI units (the black boxes) and the two trigger coils on the front plate.

The unit seems to work well, the bike starts easily and runs well. It seems to be well made as far as the machining of the metal components. It is dead easy to set the timing up.

My concerns with it are the quality of the CDI units, I think they could be better. They are literally just glued in with silastic and there are a mass of wires jammed inside, it could all be a lot neater.

These things are just one of the systems available to replace  the original magneto.
Title: Re: Is electronic ignition the way to go?
Post by: alanp on 10.12. 2012 11:16
As has been said, electronic ignition is fine if accompanied with modern alternators. It seems to me that some of my classic riding friends who converted to electronic ignition have changed back to magnetos due to the problem of keeping the battery voltage sufficiently high.
Now, this may/will be aggravated by using cheap batteries or duff dynamos or failing to put their batteries on Optimate chargers when the bike isn't run for some weeks or using an old car type battery charger now and again in the belief this will do the trick, so each circumstance is different.
My advice would be that if you really must go the electronic route buy a good battery (not the cheapest you can find), get your dynamo checked by a good source, buy an Optimate charger and connect it up before you close the garage door until the next decent weekend run.
However, if you don't want to be this organised maybe they're not for you.
Title: Re: Is electronic ignition the way to go?
Post by: muskrat on 10.12. 2012 11:47
 OK I'll be the odd one out. Boyer on all 3 BSA's. First tried it on the A7SS racer, and started winning. Put one on the '51 A7 and luv it. Dynamo is good, use 2 x 6 volt gel bat in line to give 12 volt through a DVR2 reg. Draws 2 amp at idle, 0 at 25MPH in 4th and +2 at 40mph. SRM dynamo belt broke once, charged battery at servo for about 2 beers and it got me 80 miles home. The best thing is it starts 1st kick hot or cold, even after a month sitting.
Cheers
Title: Re: Is electronic ignition the way to go?
Post by: bsa-bill on 10.12. 2012 14:53
Quote
Now, this may/will be aggravated by using cheap batteries or duff dynamos or failing to put their batteries on Optimate chargers

Think you have a point or two there Alanp, I fitted a Pazon unit and it's cured my problems starting and running my RGF, however I do have a problem with the battery losing charge and had no time of late to investigate could be one of a few things

1. Battery - seems to me even expensive ones are cheap these days, I had a battery on my Flash for six years or more and never had to charge it after winter, had three replacements for it since they last about a year two if your lucky.
2. regulator it's a vreg, think I read they can let the battery leak down, in fairness it did get a couple of leads reversed after a senior moment so ??

I rate the Pazon though the bike starts and runs well with no pinking that was evident with the maggie and contrary to what I have read it does not run the battery down if left on ( yes another senior moment).
Of course the Pazon could be hiding other faults that I have not uncovered and yes I would like the bike to run on a maggie but I need to get it checked out and a fault found, it had been refurbished and runs on the Flash quite well so maybe it just dont like alloy
Title: Re: Is electronic ignition the way to go?
Post by: Triton Thrasher on 10.12. 2012 18:10
Quote
It depends on you way of thinking.

 I believe electronic ignition is the way to go. Just look at all the cars on the road, most have electronic ignition. zero have mags (maybe a few veterans) and only older classic cars have contact breakers and most of those have electronic conversions. How many do you see broken down at the side of the road with failed spark?
I have had a Lucas rita on my Velocette for 30 years and you get full high intensity spark even if you kick over slowly, does not get weaker when hot. Majority of classic bikes that are difficult to start can trace it down to a mag.

New electronic ignitions  can be cheap and are reliable, newer ones less than £20 such as http://www.ebay.co.uk/itm/Powerspark-45D-ELECTRONIC-IGNITION-KIT-for-Lucas-43D-45D-59D-Distributors-/360508264952?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item53eff791f8 so viable to carry a spare.  The expensive part is the mechanical magneto replacement, but I bought a complete lucas RITA replacement  A10 kit on ebay for £80, so they are available without paying £200+,  there is one at £60 on ebay at the moment with single spark but easy and cheap to change to twin. http://www.ebay.co.uk/itm/Lucas-Magneto-replacement-electronic-ignition-kit-Triumph-BSA-Norton-Vincent-/330842117269?pt=UK_Motorcycle_Parts&hash=item4d07ba1495

The downside as mentioned is the need for reliable electrics. Well if you don't have a working dynamo or alternator, lights etc  then maybe you should not be using your bike anyway? If you have the later alternator instead of a dynamo then you can normally get a good spark with a flat battery on kick over, I can on my Velo with alternator conversion.

Magnetos have been around for a long time and many find they work well. Later capacitors increase reliability but don't forget the old 60 year old bearings, flaky points and brushes.  If you are half way round the continent and the mag fails??? .

Originality is important to some people, I think the mag replacement points holder looks right (was fitted as standard to some British bike when mags dried up in  1969-70, Velo Thuxton being one.) But I want reliability and consistent high intensity spark and good starting so my Lucas competion magneto will stay on the garage shelf .

Of course modern vehicles use electronic ignition and it's better than a magneto.

If someone was actually selling electronic conversions to modern vehicle standards, for old bikes, I might be interested, but they're not.

The possible exception  was the RITA. Coincidentally, that's the only one of the conversion systems that made it onto production bikes. The idea of a factory and dealers selling thousands of bikes with Boyers would be bizarre.

A working magneto starts perfectly, hot or cold, wet or dry. It can't be only my one!  The possibility of cowboy traders pretending they can fix magnetos does not take away from that.

 Touring Europe with flaky points and brushes and 60-year old mag bearings would be a strange thing to do, obviously.
Title: Re: Is electronic ignition the way to go?
Post by: Housewiz on 10.12. 2012 18:50
Here is the mag conversion I found.  http://www.petersclassicbikeparts.nl/contents/en-us/d265.html

Comments??

Thanks,

Steve
Title: Re: Is electronic ignition the way to go?
Post by: metalflake11 on 10.12. 2012 18:58
Personally, I think it's luck of the draw. I have worked out, (roughly) that I have had one problem every five years with the same two magnetos over a period of 35 years. This includes the points plate coming off its taper and the earth kill brush breaking and causing a permanent earth, so no spark. The first took half an hour to fix, and the other about two minutes. The only other problem has been difficulty starting when the mag got warm, which is almost always the condensor failing. Not once have I had to recover the bike due to it's failure! On the other hand, I put a brand new Boyer on my 750 Bonnie and had a nightmare, the bike started easily, ran perfectly for about five miles and then complete ignition failure. After about twenty minutes it would start and run for another five miles and conk out again. Working on my long held belief that electronic ignition either works or doesn't, I went on to spent lots of time and money trying to get to the bottom of it. Eventually the unit went back to Boyer and they sent me another saying the first one was faulty. (The service incidentally was fantastic, I posted the old unit on Tuesday and had the new one back by Friday. No charge either). The other half had a new VW Golf which would cut out completely, and then start after anything from a few moments, to a few hours.
I look at a mag as a single item, one which is full of sparks and will usually give you plenty of warning of a developing problem. Changing it is an easy and relatively quick thing to do. As such, if a problem develops that I cannot rectify by changing pick ups and brushes, leads, caps and plugs, I put my other mag on and send the origional to a reputable restorer. Being a single  and compact ignition unit, it is not hard to find space for your spare if a long journey is ahead of you, which is another plus point. I think this is the principal with light aircraft which have two complete systems that you can switch from one to another. No doubt an electronic jobbie will have your engine running better with its progressive mapping, rather than the advanced or retarded and nothing inbetween with the auto advance.
My advise would be fit what you want and then rub a rabbits foot!
.......Good Luck!
Title: Re: Is electronic ignition the way to go?
Post by: morris on 10.12. 2012 20:15

Thanks lads, I was thinking about going for electronic ignition, but now you only got me more confused

Or not?

When I come to think about it, my A10 starts and runs very well on it's magneto and 6 volts electrics.
To convert it, it would need upgrading to 12V + ignition conversion kit.
The price of the package could get you a lot of other goodies, not to forget the Christmas gift for the one you love.....
Title: Re: Is electronic ignition the way to go?
Post by: Triton Thrasher on 10.12. 2012 21:20
I'm not partisan about silly old bike parts. There's no doubt that Lucas could have made a much better magneto than the K2F, had they put their mind to it, but the way things are, I think many A10 owners will have a better riding experience with a magneto, than with a proprietary electronic conversion.
Title: Re: Is electronic ignition the way to go?
Post by: chaterlea25 on 10.12. 2012 22:26
HI All,
I must admit to being a magneto fan *smile*
As said in a post above most problems come from neglect or wet
Another issue is so called "expert refurb", I recently posted a link to an article on magnet0 refurb and testing
One of the main things I learned from the article is that probably 30% of the magnetism is lost once the armature is removed

Another misnomer is that modern cars have trouble free electronic ignition *sad2*
A lot of them give trouble !! particularly those coil/plugcap thingys,

Cheers
John
Title: Re: Is electronic ignition the way to go?
Post by: Housewiz on 10.12. 2012 22:42
Hey John,

Think I missed that mag referb article.  Mind posting the link?

Thanks,

Steve

Title: Re: Is electronic ignition the way to go?
Post by: orabanda on 11.12. 2012 02:37
So, therein lies the case for a diesel A10; it will never stop (if you manage to get it started!).
Title: Re: Is electronic ignition the way to go?
Post by: metalflake11 on 11.12. 2012 03:37
Something not mentioned so far, is where do you live?........... I live in a big city in England and it is winter and dark most of the time. To give an example, a trip to work and back includes 68 sets of traffic lights and heavy stop/start traffic over a distance of about twenty miles.  In contrast, a mate of mine lives on Anglesey Island and travels a thirty mile round trip to work and has two sets of lights, and no traffic jams.
Given that you need a decent amount of juice in your battery to run electronic ignition, what might be a good idea for him would not be a good one for me. Indeed, mine has gone flat before now, but the mag has got me home.
Just a thought! Rob.
Title: Re: Is electronic ignition the way to go?
Post by: Housewiz on 11.12. 2012 04:28
No diesel for me - I just want to find a set of 750cc barrels under my x-mas tree - some year I hope.  *smile*

Thanks,

Steve
Title: Re: Is electronic ignition the way to go?
Post by: RichardL on 11.12. 2012 05:54
Well, I like the magneto for the sheer oldness of it. I don't ride as many miles as some of you, so it might not be the same issue. Not old is the Bright Spark capacitor I added, only to find that my bike was suddenly easy to start. First kick when cold, a few when warm, but I think that's fuel not mag. Now, as for mags in airplanes, one thing I'm sure Brian knows, but didn't mention, is that there are two of them and two plugs in each cylinder.   

Richard L.   
Title: Re: Is electronic ignition the way to go?
Post by: Brian on 11.12. 2012 06:52
So there you go Steve, lots of different thoughts and ways of looking at it all.

Ultimately its up to you to decide which way to go, electronic or magneto.

I dont doubt for a moment that electronic systems provide a good spark and the bike will run well with one fitted. You still have to consider that the electronic systems, with the exception of the BTH system, all require a external power source. Its reliability will dictate how reliable the ignition system will be.

A magneto is a totally independant unit, however as has been pointed out it must be in good condition and rebuilt by someone who knows what they are doing.

Magneto's do not rely on 60 year old bearings etc, if the unit is rebuilt by a competent person it will be virtually "as new".

If you decide to stay with the magneto get it rebuilt by someone with a good reputation and who is prepared to give at least a years warranty on workmanship and parts.
Title: Re: Is electronic ignition the way to go?
Post by: stu.andrews on 11.12. 2012 09:29
If you need to have a magneto refurbished go to Paul Lydford of APL Magnetos in Hampshire, tel 01747-852136. You will not be disappointed. (I have no business connection.)
Title: Re: Is electronic ignition the way to go?
Post by: iansoady on 11.12. 2012 11:45

One of the main things I learned from the article is that probably 30% of the magnetism is lost once the armature is removed

Cheers
John


I think that's true of early mags but understand that later ones like our K2Fs with alnico magnets are OK. It's true that Lucas (like Amal) did build down to a price but they could make good magnetos like the competition and wader models.
Title: Re: Is electronic ignition the way to go?
Post by: RichardL on 11.12. 2012 12:39
Just so I don't overstate the situation, I should have mentioned that when I installed the Bright Spark cap I also remagnetized the magneto. So, maybe the succes was a combination of both.

Richard L.
Title: Re: Is electronic ignition the way to go?
Post by: chaterlea25 on 11.12. 2012 13:12
Hi Steve,
Mag repair article link
http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=446733#Post446733

Brian,
I had to strip a B-T-H mag which had been on a bike which got flooded, (in water)
 I only removed the end cap which had let water in  *ex* (it shouldnt)
I agree the way the electrics are assembled is poor, I had great difficulty getting the wires to the gubbins in the end cap attached so as they would not foul the rotor  *angry*
Another (maybe) disadvantage of the B-T-H is that they need a minimum rotational speed to spark, A problem for older or lightweight riders!!

Ian,
Yes and no!!!! K2F's and similar have better magnets than the old horseshoe magnet types, so maybe keep a bit better
There is no such thing as "an internal keeper" this would in effect "short out" the magnetic field

Regards
John

Title: Re: Is electronic ignition the way to go?
Post by: Brian on 11.12. 2012 21:25
Funny you should mention the wires John, after I had repaired the unit I was working on I e-mailed the manufacturer with what I thought were a couple of sensible improvements. I suggested the centre shaft should be shrouded as after I fitted the CDI unit it took a lot of fiddling to get the wires to sit clear of the shaft.

Another area I thought needed attention was the arm on the end that swings past the trigger coils. The position of that arm on the shaft is critical, fortunately for me I marked it before I removed it. I said to him if the position is so important then the arm should fix on a square or keyway or something so it can only go on in the right place.

Cranking speed is always a issue on self generating electronic ignition systems like this one. Systems like the Boyer that are powered by a battery are fine but it can be a issue on self generating ones. I used to work in the lawnmower/chainsaw industry and came across this as a problem quite often. If something is not set quite right then the cranking speed required to produce a spark can raise considerably to the point that you simply cant start the engine.

Title: Re: Is electronic ignition the way to go?
Post by: KiwiGF on 12.12. 2012 00:42
Here's my 2 cents worth. I'm in the electronic ignition camp! Mainly because I have bad memories of constantly messing about with points and trying to get the ignition timing right. So I bought a new style BTH mag, which is self powered and does not need a battery to work.

The new BTM mag is great in principle and looks the part as well, but I have some doubts about the quality of manufacture. I had issues with the "locking pin" BTH timing method being very

inaccurate (I posted this elsewhere on this forum) that I think had resulted from not keeping to manufacturing tolerances, coupled I guess with poor quality control as the issue was not picked up by

the manufacturer. I suppose you could say this of a lot of the aftermarket products for the A10! (but the mag is not cheap so having to "fettle" it is a bit annoying).

The cap on mine also showed signs of being filed by hand to make the rubber grommet fit where the wires enter the mag, but its' still a faff getting that grommet in place after removing the cap, and it's never going to stop water or petrol getting into the electronics so I fitted the mag so the grommet is facing downwards.

Inside the cap of the mag there is a fair bit of sealant used to keep wires from moving about, this does not seem the best way of doing the job but it is better than nothing (see pic). It did make it difficult to remove the cap for the first time, as the sealant used had (accidentally) stuck the cap on. Of course there should never be any NEED to remove the cap.

To be fair BTH offered to replace the mag due to the fault with the locking pin but due to the cost of shipping to/from NZ I decided to keep the mag and time the engine using a "home made" method on

the basis I would not have to do the timing again, unless I had to remove the mag or drive gear for any reason.

The mag is a direct replacement for the std KTF but I found the BTH mag casing hits the A10 crankcase so you end up not having much timing adjustment available from the mags 3 slotted stud holes.

The 2 coils the BTH comes with I wondered where to  fit for quite a while, as I did not want to drill holes in the frame and I did not want to rigidly bolt the coils to the frame and possibly have them fail due to vibes, in the end I simply wrapped the coils in a bits of rubber inner tube and (comprehensively) cable tied them to the frame, HT lead pointing forwards, and directly underneath the front seat mounting lug, and almost out of sight.

The special extra long bolt for the bottom stud holding the mag on cannot be used with the BTH as the casing gets in the way, so a std nut is needed instead for that stud, which is a PITA to tighten!
 

The spark looks very "weak" from the BTH compared to a std mag (BTH claim that is "by design" and not an indication of a problem) to the point it can only be seen in the semi dark but the bike starts

fine with a "normal" kick. I've found the plugs are a bit prone to needing a dry if the carb floods the engine, but I've hardly ridden the bike so time will reveal all.


Lastly, there is very litle info available on how to fix or service the new style BTH mag, this may or may not be a problem depending on whether they need fixing, or wear out!
Title: Re: Is electronic ignition the way to go?
Post by: chaterlea25 on 13.12. 2012 16:03
Hi All,
Yea they look messy inside  *sad2*
On the single cylinder one I worked on, theres an electronic pack (CDI??) fitted into the end of the end cap
so the wires going to it are very near the rotor end flying around  *sad2*
it took a lot of fiddling to get them restuck in place  *problem*

Cheers
John
Title: Re: Is electronic ignition the way to go?
Post by: KenF on 16.12. 2012 08:19
A few posts on this thread seem to have drifted away from the original question about electronic ignition, but just to complete the picture ...

.....
One of the main things I learned from the article is that probably 30% of the magnetism is lost once the armature is removed
.....
Cheers
John

That sort of figure is true enough for some magnetos, John.

I recently measured a BT-H KC2. From its fully magnetised state with armature aligned with the pole shoes, its magnet lost 6% of its strength the first time the armature was rotated half a turn, and it then lost an additional 21% of its initial strength when the armature was first removed from the magneto body. Those losses are permanent until the magneto is remagnetised. However, the loss of magnet strength upon removal of the armature can be avoided by placing the magneto body in an external keeper before the armature is removed and leaving it there until the armature is replaced. A heavyweight cast-iron vice with 6" jaws is ideal for the job. Any work on the mag body, such as replacing the drive-end bearing, then needs to be carried out while the mag body is in the external keeper.

.....
I think that's true of early mags but understand that later ones like our K2Fs with alnico magnets are OK.
.....

You're quite right that the K2F doesn't suffer anywhere near as badly as the KC2 from removal of the armature, Ian. I did a similar test to the above on a K1F (which has an identical magnetic circuit to the K2F). There was a 3% drop in magnet strength when the armature was initially rotated, and a further drop of only 2% when the armature was first removed and replaced. However, it's more to do with the design of the pole laminations cast into the magneto body, that the mere fact that the K2F has an alnico magnet. Most, if not all, of the post WW2 Lucas rotating-coil magnetos and magdynos have what I call a 'self-keepering' feature. It's explained in some detail in Self keeper explanation (http://brightsparkmagnetos.com/faqs/FAQs%20about%20magnetism%20and%20remagnetising/What%20is%20a%20keeper,%20and%20do%20I%20need%20to%20use%20one%20if%20I%20take%20the%20armature%20out%20of%20my%20rotating-coil%20magneto.htm) on my company's web site.

.....
There is no such thing as "an internal keeper" this would in effect "short out" the magnetic field
Regards
John

True enough that if an internal keeper completely shorted out the magnet, the magneto wouldn't be much good. But, sure enough, the Lucas K2F magneto and most, if not all, of their post WW2 rotating-coil magnetos and magdynos do have an 'internal keeper' or 'self keeper', which is clearly visible in the armature cavity of the magneto body opposite the magnet. It partially shorts out the magnetic circuit. The earliest reference I've found to this is in Bosch's British patent 171087  (http://worldwide.espacenet.com/maximizedOriginalDocument?flavour=maximizedPlainPage&locale=en_EP&FT=D&date=19230226&CC=GB&NR=171087A&KC=A) dating back to 1920. There, Bosch start by saying:
To combat this they describe that a
They conclude by saying:

Adopting this feature is what enabled Lucas to be able to say in their Workshop Instructions for the N1, KN1, K1F, K2F and KVF magnetos (http://brightsparkmagnetos.com/library/LWImags/Motor%20cycle%20magnetos%20N1,%20KN1,%20K1F,%20K2F,%20KVF,%20Sec%20L-5,%20Pt%20A.pdf) and also for the MO1L and MN2L magdynos (http://brightsparkmagnetos.com/library/LWImags/Motor%20cycle%20magdynos%20MO1L,%20MN2L,%20Sec%20L-5,%20Pt%20B.pdf):

All the best,

Ken.
Title: Re: Is electronic ignition the way to go?
Post by: muskrat on 16.12. 2012 09:44
 Great explanation Ken, even I sort of got it. Mags have always been magic to me.
I'm in the electric ignition camp, probably for that reason. Being a young bloke of 51 mags had just about disappeared by the time I started riding.
I just remember fiddling with the A7's mag and even got it serviced by Peter Scott. It went OK but when I retired the racer and put it's Boyer on the '51 performance increased by at least 25%. All 3 of my BSA's have it and 2 start 1st kick hot or cold every time the other (A65) takes 2 kicks. Yes a good charging system and battery are a must. If the dynamo wants a rest (stops working due to broken belt/chain) a 4 amp battery will run them for about 80 miles (1 hour at my speeds LOL).
Cheers
Title: Re: Is electronic ignition the way to go?
Post by: Rocket Racer on 18.12. 2012 09:02
I also bought a BT-H unit for my race bike, but was underwealmed by the short duration pale spark. Came to the conclusion that a magneto should throw a far longer duration spark and burn more methanol, so reduce bore wash. So the BT-H will go on a road engine.
I then invested in a Joe Hunt, flange was too thin carried the taper too far out, had to mill my crank cases to get it to fit and it still failed within two seasons, faulty coil  *sad2* Have had that coil replaced and will persevere but nothings ever easy.
I do like the fact that a magneto powered race engine only has a kill wire, whereas with coils and electronics... wiring faults are very common in the pits.
My single has a mag and has been a reliable beastie if not parked in the rain.
Title: Re: Is electronic ignition the way to go?
Post by: Russ on 09.01. 2013 01:09
Hi Brian

I have a magneto and generator which are complete, but I have no idea what condition they are in as I haven't started my project yet, but as I read this post I thought I might as well start somewhere.
I'm with you, I like the idea of having the original equipment fitted.
Can you suggest where in Aus is a reliable place to get these refurbished or perhaps this is something you do yourself.
I'm in Traralgon.  Victoria.

thanks Russ
Title: Re: Is electronic ignition the way to go?
Post by: cyclobutch on 09.01. 2013 10:22
Yeah - I had both the mag and dynamo refurbed when I was doing the rest of the bike. I left it all 6 volt, and I'd have to say I'm more than happy with the lighting for night time riding too. I'm OK with being left with a very occasional fiddle with the points. Electronic ignition, 12V conversions, belt drive dynamos all just look to move the problems elsewhere.
Title: Re: Is electronic ignition the way to go?
Post by: Topdad on 09.01. 2013 11:19
Well Steve ,bet you didn't expect all this feed back when you first posted , just shows the breadth of experience from all the proceeding guys with as you'd expect a different view depending I'd think from  personal experience gained over time all very pertinent but in the end down to you mate whichever route you go down don't skimp ,if mag ;get it refurbed ( I used the guy mentioned a couple of posts back and absolutely not probs with my mag and wouldn't part with it after 9 yrs ) if eleccy ingnition go for the best you can afford ,as you may guess I'm firmly in the maggy camp simply due to having memories of having to sort out so many Trumpet mates bikes when the battery failed or coil or condenser etc but that was over 35 yrs ago plus and I know things must have improved but  honestly can't remember ever suffering loss of sparks when I was a kid  on my A10 , I even submerged the bike totally in a flood once simply pulled it out with the fire brigades help and  dried it  and me out  with wd 40 ( the bike that is ) and a cloth and we were on our way to kent within 1/2 an hour running completely on song. interesting post best wishes BobH
Title: Re: Is electronic ignition the way to go?
Post by: bsa-bill on 09.01. 2013 17:19
whichever you choose to supply the spark at the end of the line lies a plug and I suspect that these days an L86 or N5 or their ilk are just not made to the same standard they used to be, the quality products now are the more modern plugs that can demand a higher price (return) for the manufacturer.
Title: Re: Is electronic ignition the way to go?
Post by: a10gf on 09.01. 2013 17:31
Quote
Is it true some bikes won't start/run when the mag gets a bit too warm?
Quoting the original 1st post, happened to my mag when I got the bike, one of the tiny winding wires from the armature lost contact when things expanded due to heat. Cannot call it an electric fault, more of a mechanical one, and due to the way the mag was refurbished once upon a time.
Title: Re: Is electronic ignition the way to go?
Post by: ian davies on 09.01. 2013 17:44
Let me put it this way, all electronic ignition conversions for classic bikes should be sold with free RAC recovery.
Title: Re: Is electronic ignition the way to go?
Post by: Viking on 10.12. 2015 10:16
Let put it the other way: All mags and mag rebuilds for classic bikes should be issued with free AA recovery.  ;)
Title: Re: Is electronic ignition the way to go?
Post by: morris on 10.12. 2015 11:40
Let put it the other way: All mags and mag rebuilds for classic bikes should be issued with free AA recovery.  ;)
Let me put it this way, all electronic ignition conversions for classic bikes should be sold with free RAC recovery.

Since I have one on electronic and another one on a mag, does that entitles me to a double coverage?  *dunno*
Title: Re: Is electronic ignition the way to go?
Post by: warmshed on 10.12. 2015 19:34
Electronic ignition is very reliable these days, unless you buy a really cheap chinese set-up.  How many cars or modern bikes do you see with reliability issues?  In all the years using electronic ignition on classic bikes only once was there a failure, ( not mine, a friends) a coil fault, this was sourced locally on our German trip and on our way.  Every time I went to Germany on a rally there was someone that had Mag problems. luckily I carried my old mag with me and was able to help one failure.
mags were good in their day and in tip top condition still great.  If you have a problem your stuffed, its a recovery job.

If you are using your bike locally then not really a problem, just pop home barrow a trailer.  If you do use the bike as they are meant to be used then electronic ignition is great to have.

Go to any show and you will see people trying to start their bike but the mag says no, especially when hot.

Each to their own but because " my mags been good for 50 years" does not make it more reliable.
Title: Re: Is electronic ignition the way to go?
Post by: Triton Thrasher on 10.12. 2015 20:49
Neither is perfect.  The magneto is far removed from the robust magnetos used on planes.

The available electronic conversions do not appear to be made to OEM automotive standard and require a power supply that could tax a 6V dynamo.

My experience with a Tony Cooper rebuilt magneto has been very good. Nothing could start more easily, hot or cold, wet or dry.  Except maybe a bike with an electric start.

Title: Re: Is electronic ignition the way to go?
Post by: terryg on 10.12. 2015 22:36
I like the 'physics at work' aspect of the magneto and its independence. It's a simple enough concept that Michael Faraday might have dreamt up. Like so much engineering it works by having the right bits, doing the right things, in the right places at the right times. If that's not the case then some servicing is called for.
Electronic ignition is good too but has a different set of potential problems, and you need a good battery and charging system.
You pays your money... etc.
Title: Re: Is electronic ignition the way to go?
Post by: Tomcat on 11.12. 2015 07:34
My 20c worth...
If the charging system is an alternator in good working order (and fitted with an electronic rectifier/regulator),  then electronic ignition is superior to points. ie on an A65
BUT... as this is an A7/A10 forum, then most discussion is related to these engines. So my advice is to have the magneto fully rebuilt by a reputable repairer, then it should be fit and forget. Peter Scott reconditioned my magneto (longstroke A7) 10 years ago, and it always starts 1st kick hot or cold......
Cheers Tomcat
Title: Re: Is electronic ignition the way to go?
Post by: bikerbob on 11.12. 2015 08:54
I have both a 1963 A65 which I converted to 12volt and ellectronic ignition no problems unless the battery runs down then if you try to start it up with run down battery then the Pazon unit goes to full advance and it kicks back quite severely reminding you that the battery needs charging has only happened once as I now keep the battery on a trickle charger over the winter. The 1956 A7 has magneto and I have no intention of replacing it with electronic ignition I have just replaced the bearings as they were rumbling I overhauled a magneto some years ago on a A10 Gold Flash and I ran that bike for 16 years until I sold it the only other thing I had to replace was the pick up brushes.
Title: Re: Is electronic ignition the way to go?
Post by: Triton Thrasher on 11.12. 2015 09:12
Somewhere out there may be the perfect electronic conversion, cheap and reliable as a chainsaw ignition.

And discreetly fitting inside the spark plug cap!

Title: Re: Is electronic ignition the way to go?
Post by: metalflake11 on 11.12. 2015 15:42
Magneto for me, and I wont be changing any time soon. I understand others trying to maximise the performance of their A10's with modern electronics, but it's not for me.
A good re-build easily lasts ten years or more, the symptoms of a failing mag are as clear as the nose on your face and if you're going a long way from home you can carry a spare one. Neat, compact and self-reliant, how can you fault that?
In all my years, only once has it let me down when the points plate came loose on my way to Kent, an hour later I was back on my way minus a points cover which had fallen off.
Title: Re: Is electronic ignition the way to go?
Post by: cyclobutch on 14.12. 2015 13:12
We get suckered into this conversation more often than most other forums get to talk oils.
Title: Re: Is electronic ignition the way to go?
Post by: shuswapkev on 20.12. 2015 12:12
I have a 50 or so A10...put a wassel hall effect ignition..i would say it worked perfectly...dead easy to time to within 1/2 degree...degree wheel and inductive light...

but...my problem was I couldn't get even charging...went to 12 volts dvr2 regulator...worked fine for a while...then gross over charging...then undercharging...I have a voltmeter on the handlebar...always keeping an eye on that.....I disconnected the dynamo on a full battery and ran on that until it stopped ...would get about 2 hours out of a 10amphr doorbell battery

at the end of it all...the electronic  ignition was great...but the constant worries of the E3L output...wasn't worth the fuss...  I have parted a magneto together with a brightspark condenser...... I have even bought a Kubota alternator...and am looking at adapting that as the sportster guys do...on the outer end of the dynamo...that gives 30 amps...they are about 3inch dia and maybe 2 inches long...permanent magnet
Title: Re: Is electronic ignition the way to go?
Post by: chaterlea25 on 20.12. 2015 13:18
Hi,
A caution about usung high output alternators on "small" bike batteries
The high current output of the alternators will damage the batteries,
One of my friends had a citroen 2CV alternator on a Vincent comet, It would ruin batteries in short order *sad2*
The problem occurs when the battery is not fully charged (bike sitting idle for a while) the alternator stuffs its full 30A output into an 8 -14AH battery *problem* *warn*

HTH
John
Title: Re: Is electronic ignition the way to go?
Post by: bsa-bill on 20.12. 2015 13:49
Quote
the alternator stuffs its full 30A output into an 8 -14AH battery

what's any voltage regulator doing or not for this to happen John
Title: Re: Is electronic ignition the way to go?
Post by: chaterlea25 on 20.12. 2015 16:03
Hi Bill,
There in lies the problem  *ex*
The regulator sees say 11.5 v , its sole function is to  get this up to its cutoout voltage paobably 14,4v
If the alternator is capable of stuffing 30A into the battery it will do this till the battery voltage rises to its cut out point
Basically tha alternators and batteries need to be matched in capacity within certain peramaters

The Kubota or similar permanent magnet alternators are probably not as hard on the batteries as excited rotor alternators but they have antother problem *problem*
They have very strong magnets so do not turn over smoothly at lower revs, rather they pulse from one magnetic pole to the next
Early Alltons suffered from this and apparently used to break the (dynamo) drive gear teeth on certain bikes *ex*
THeres a guy in USA or Canada who has devloped the Kubota for use on Vincents, I believe it uses some kind of centrifugal cluth

I went through the ups and downs of fitting such an alternator to the A10, but abandoned it due to complexity and the issues mentioned
The thoughts of broken timing gear teeth and then valves hopping off the pistons put me off the idea *pull hair out*

The 12v dynamo with belt drive and Podtronics regulator have been 110% relaible so far *whistle*
So this is what I have recommended to my customers to go with, (DVR2 regs on those)

Cheers
John



Title: Re: Is electronic ignition the way to go?
Post by: bsa-bill on 20.12. 2015 16:53
Thanks John
Seems a long time since a battery was a battery was a battery.
Back in the sixties it used to be an item that you'd have to replace every year or two, my Focus is an 07 and still on it's original battery, gets serviced once a year and not anything more in between than an oil check ( and that never varies), OTOH I got sick of buying those big yellow lanterns (millions of candle power) that have lead acid cells in them that must never run down or be overcharged or they die.
I've just bought one with LI-on battery, seems to last for ages between charges, must say I'm impressed with this Lithium stuff, got most of my cordless tools changed to them, quite a surprise to go to them and find they're full charge even after sitting in a cabinet for months.
Now when are they going to make them for bikes *smiley4*
Title: Re: Is electronic ignition the way to go?
Post by: warmshed on 20.12. 2015 20:28
Bill,   motorcycle lithium battery  http://www.amazon.co.uk/s/?ie=UTF8&keywords=motorcycle+lithium+battery&tag=googhydr-21&index=aps&hvadid=74772936254&hvpos=1t2&hvexid=&hvnetw=g&hvrand=14433422312069977893&hvpone=&hvptwo=&hvqmt=b&hvdev=c&ref=pd_sl_5xnh3m7174_b
Title: Re: Is electronic ignition the way to go?
Post by: bsa-bill on 20.12. 2015 22:30
 
Quote
Bill,   motorcycle lithium battery

Cheers