Fitting a magneto to Maney crank cases

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Fast Eddie

Fast Eddie

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I’m specifically talking about a mag behind the cylinders, not on the points housing.

Has anyone done this?

I know some Commandos had a flange mounting there, for the stillborn early electric start design. Maney cases do not have this, but they are quite thick. I’m wondering if it’s possible / safe to machine the case to accept a Joe Hunt type mag?
 
Fast Eddie said:
I’m specifically talking about a mag behind the cylinders, not on the points housing.

Has anyone done this?

I know some Commandos had a flange mounting there, for the stillborn early electric start design. Maney cases do not have this, but they are quite thick. I’m wondering if it’s possible / safe to machine the case to accept a Joe Hunt type mag?
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Didn't commoz do this on one of his motors ?
I'm sure I remember seeing one on here by him
 
That was done by several folks back in the day to fit ARD and other mags to Commando 850 cases. I had one on a race bike for a while, but unfortunately didn't take any pictures. I do have pictures of some of the parts involved, posted below. I don't see any reason you couldn't do the same with Maney cases.

I do have this picture from someone else's bike with the conversion done by HPI, probably in the late '70s or early '80s.

Fitting a magneto to Maney crank cases


This is the ARD mag with adapter plate.

Fitting a magneto to Maney crank cases


This is a collection of parts used to modify the timing side, using Atlas parts.

Fitting a magneto to Maney crank cases


And the inner side of the modified timing covers.

Fitting a magneto to Maney crank cases


And the outside of the timing covers.

Fitting a magneto to Maney crank cases


Ken
 
lcrken said:
That was done by several folks back in the day to fit ARD and other mags to Commando 850 cases. I had one on a race bike for a while, but unfortunately didn't take any pictures. I do have pictures of some of the parts involved, posted below. I don't see any reason you couldn't do the same with Maney cases.

I do have this picture from someone else's bike with the conversion done by HPI, probably in the late '70s or early '80s.

View attachment 99634

This is the ARD mag with adapter plate.

View attachment 99638

This is a collection of parts used to modify the timing side, using Atlas parts.

View attachment 99635

And the inner side of the modified timing covers.

View attachment 99636

And the outside of the timing covers.

View attachment 99637

Ken
Click to expand...
Great info Ken, thank you.
 
texasSlick said:
You will never be left on the road due to a flat battery.

More spark energy at top end than a coil ignition.

Slick
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Right you are. I'm wondering why Nigel is doing it on his new build. Those two reasons are well known. I was thinking it might not be quite that simple. However, maybe it is that simple.

I took a magneto off a magneto motor. Never a glitch since on a street only bike, and my lights stay bright at idle. That reminds me maybe I should go check my battery voltage.
 
lcrken said:
That was done by several folks back in the day to fit ARD and other mags to Commando 850 cases. I had one on a race bike for a while, but unfortunately didn't take any pictures. I do have pictures of some of the parts involved, posted below. I don't see any reason you couldn't do the same with Maney cases.

I do have this picture from someone else's bike with the conversion done by HPI, probably in the late '70s or early '80s.

View attachment 99634

This is the ARD mag with adapter plate.

View attachment 99638

This is a collection of parts used to modify the timing side, using Atlas parts.

View attachment 99635

And the inner side of the modified timing covers.

View attachment 99636

And the outside of the timing covers.

View attachment 99637

Ken
Click to expand...
Sorry to say FE but look at all the crap you have to install and all the mods you have to go through just to fit behind the motor, I know your not interested in installing one off the point's timing cover so all good there, thing is as well having a maggie sitting behind a hot motor is a worry of over heating the maggie, I have had 2 British motorcycles running Joe Hunts first one a 2 rare earth JH on my 81 Triumph Thunderbird that I clocked up 250k trouble free km's with the JH and the last 13 years now with the 4 rare earth JH on my Norton, no need to retarting it for starting first kick every time even when it's been sitting for sometime and hanging out in the cool air flow and the best thing above all easy to pull off to do any maintenance, but so far in 13 years I haven't touched it except for taking the top cover off to put a few drops of STP on the lube pad for the point's cam, yes it sticks out but I have been down 2 x now on the maggie side and the JH has survived each time, yes different story if set up on a race bike and the risks of coming off at high speed but my mate raced his race Triumph with a JH sticking out the side, using soft bolts that sheer off if he went down that side, by the way I ended up with that JH for my old Triumph after he stopped racing, anyway thought I throw in my 2 bob's worth.
Jim Smit be someone to talk to as well about installing behind the motor as he has his set up on his test bike with all his goodies, but I have never had any problems with mine sitting out in the cool air, set up and tuning is so simple where it is, by the way I also use the soft bolts just in case.
Everyone has their opinion on where it should be mounted, but most people have never had a JH maggie or a maggie period, for simplity and huge spark a Joe Hunt is great from running at low speed to going flat out, faster they spin the bigger the bang no matter where it's mounted and they are so fu.king reliable and a 5 minute job replacing the condenser, the tune up kits are cheap comes with new point, condenser and plug leads for about $35 from JH, but so far still running the original points in mine with well over 35k miles on it and it still starts first kick every time.
Al don't compare a Joe Hunt to the old lucas maggies as the Joe Hunts are so much simple to work on and a 5 minute job to change a condenser compared to the Lucas maggie as I have a competition Lucas maggie for my Manxman project bike, don't even come close to a JH maggie.

Ashley
 
ashman said:
Sorry to say FE but look at all the crap you have to install and all the mods you have to go through just to fit behind the motor, I know your not interested in installing one off the point's timing cover so all good there, thing is as well having a maggie sitting behind a hot motor is a worry of over heating the maggie, I have had 2 British motorcycles running Joe Hunts first one a 2 rare earth JH on my 81 Triumph Thunderbird that I clocked up 250k trouble free km's with the JH and the last 13 years now with the 4 rare earth JH on my Norton, no need to retarting it for starting first kick every time even when it's been sitting for sometime and hanging out in the cool air flow and the best thing above all easy to pull off to do any maintenance, but so far in 13 years I haven't touched it except for taking the top cover off to put a few drops of STP on the lube pad for the point's cam, yes it sticks out but I have been down 2 x now on the maggie side and the JH has survived each time, yes different story if set up on a race bike and the risks of coming off at high speed but my mate raced his race Triumph with a JH sticking out the side, using soft bolts that sheer off if he went down that side, by the way I ended up with that JH for my old Triumph after he stopped racing, anyway thought I throw in my 2 bob's worth.
Jim Smit be someone to talk to as well about installing behind the motor as he has his set up on his test bike with all his goodies, but I have never had any problems with mine sitting out in the cool air, set up and tuning is so simple where it is, by the way I also use the soft bolts just in case.
Everyone has their opinion on where it should be mounted, but most people have never had a JH maggie or a maggie period, for simplity and huge spark a Joe Hunt is great from running at low speed to going flat out, faster they spin the bigger the bang no matter where it's mounted and they are so fu.king reliable and a 5 minute job replacing the condenser, the tune up kits are cheap comes with new point, condenser and plug leads for about $35 from JH, but so far still running the original points in mine with well over 35k miles on it and it still starts first kick every time.
Al don't compare a Joe Hunt to the old lucas maggies as the Joe Hunts are so much simple to work on and a 5 minute job to change a condenser compared to the Lucas maggie as I have a competition Lucas maggie for my Manxman project bike, don't even come close to a JH maggie.

Ashley
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Actually Ash, I pretty much agree with you. But this is a track bike, and track bikes have a much higher propensity to be thrown down the tarmac. So one does have to think more about that and try to build a bike that’s as easy to repair as possible after a spill. The risk of wiping out the ign and even potentially damaging the now irreplaceable Maney cases from a spill, with a points mounted mag, is just too high.
 
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Schwany said:
What is the driving motivation behind installing a magneto?
Click to expand...

Its a track bike and will have no charging system. So the choice is either a total loss battery powered system, or a magneto. I’m not interested in some of the newer self generating systems as I’ve never used them and, frankly, am not convinced they would give the spark energy I’m im looking for.

I‘ve used mags before (road and track) and been very happy with them. The benefits of modern EI with easier kick starting, idle stabilisation, etc, are of no value on a track bike. A big spark, reliability, and reduced ‘faff’ are the main points of value.

A total loss system requires more faff like the taking of spare batteries and a generator to events. It’s also much more likely to fail than a good mag (way more DNFs at your average vintage event due to flat batteries vs failed mags).

And as Slick said, the high rpm performance of a magneto is likely to be better, useful when you’ve got big CC’s with a high CR.

But, as Ash said, it’s not an easy job… I wish I lived next door to Ken…!
 
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As our American cousins would say; I'm getting out the popcorn for this one ;)

The fat spark of a magneto and the high RPM stability are attractive, and the Norton installation will rely on a chain drive which will be slightly more stable than the cam mounted ignition.
I can't help thinking that for the effort involved, a crank-mounted ignition and well-matched coils would yield identical performance, and a programmable ECU would give flexibility that the mag could never deliver. It seems to work for the race bikes I've seen.

Nevertheless, a great engineering exercise, and I'll be watching with interest.
 
I use a Boyer with a very small 12 volt lead acid battery. The battery is good enough to last about 12 rides over 3 days. I have been looking for a similar sized lithium battery. The only suitable seem to be intended for cameras.

Talentcell Rechargeable 12V 6000mAh/5V 12000mAh DC Output Lithium Ion Battery Pack for LED Strip and CCTV Camera, Portable Li-ion Battery Bank with Charger, Black (Multi-led Indicator) : Amazon.com.au: Electronics

Talentcell Rechargeable 12V 6000mAh/5V 12000mAh DC Output Lithium Ion Battery Pack for LED Strip and CCTV Camera, Portable Li-ion Battery Bank with Charger, Black (Multi-led Indicator) : Amazon.com.au: Electronics
www.amazon.com.au
 
I have looked at running a pvl system on a commando from my Drixton Honda K4. A neat thing & will fit even with a belt drive but now probably a 15 year old system? Again lots of parts hanging out of the chaincase, which is the reason I didnt use Steves outrigger ignition with 3 studs off the engine case. Full fairing required really.
I know where your coming from with the magnito but cant face all the machining to those cases.
 
Fast Eddie said:
Its a track bike and will have no charging system. So the choice is either a total loss battery powered system, or a magneto. I’m not interested in some of the newer self generating systems as I’ve never used them and, frankly, am not convinced they would give the spark energy I’m im looking for.

I‘ve used mags before (road and track) and been very happy with them. The benefits of modern EI with easier kick starting, idle stabilisation, etc, are of no value on a track bike. A big spark, reliability, and reduced ‘faff’ are the main points of value.

A total loss system requires more faff like the taking of spare batteries and a generator to events. It’s also much more likely to fail than a good mag (way more DNFs at your average vintage event due to flat batteries vs failed mags).

And as Slick said, the high rpm performance of a magneto is likely to be better, useful when you’ve got big CC’s with a high CR.

But, as Ash said, it’s not an easy job… I wish I lived next door to Ken…!
Click to expand...
Makes sense on a track only bike with no charging system.

Doesn't make a bit of sense to "me" to go to the trouble of converting a perfectly good working street bike with a charging system that isn't machined to support a magneto to a magneto bike now days. The dual gears, chains, AAU and magneto add weight to a bike with a charging system, and magnetos behind the barrels are fiddly to setup. The extra spark would not be noticed as a big improvement on the street.

I have had a magneto fail on my P11, but I was close enough to home to push it back. Rare, but not that rare with the old K2 magneto.

You going to do a build thread on this project? If not, what cam is going in this race motor?
 
Fast Eddie said:
I’m specifically talking about a mag behind the cylinders, not on the points housing.

You need the Atlas parts as shown in Ken's photos - timing gears and auto advance if you want that. Easiest way is to find an Atlas timing side case and copy it. I love the mag behind cylinders setup and I live in the summer brain melting heat of Fresno Calif and never have any problems with heat effecting the mag.
Click to expand...
 
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