• Welcome to the website of the Vincent H.R.D. Owners Club.

    Should you have any questions relating to the Vincent H.R.D. Owners Club, or Vincent H.R.D. motorcycles in general, please contact Graham Smith, Hon. Editor and Webmaster by calling 07977 001 025 or please CLICK HERE.

    You are unrecognised, and therefore, only have VERY restricted access to the many features of this website.

    If you have previously registered to use this forum, you should log in now. CLICK HERE.

    If you have never registered to use this website before, please CLICK HERE.

Alton & electronic ignition

scout

New Website User
Non-VOC Member
I have a Comet with a Kirby Rowbotham electronic ignition, a Boyer regulator & a three phase Alton alternator fitted.
When the battery is showing over 12.2 volts everything runs very well.
Over a period of 50 or so miles the battery discharges to about 12.05 volts, despite the ammeter showing 2-3 amps over 30 mph in 4th. It then stalls & stops etc. This, with nothing other than the ignition working except occasional use of the stop light (LEDs)
The battery is nearly new & works well in an old Triumph m/c.

Anyone any idea where the current is going?
 

CollingsBob

Well Known and Active Website User
VOC Member
I thought an Alton would produce 85 - 90 watts at moderate cruising speeds...have you tried riding in third gear?..30 mph in 4th gear isn't turning the alternator very fast...and I think your big end will enjoy the extra revs as well..
 

bmetcalf

Well Known and Active Website User
VOC Member
The three phase Alton has been replaced by a new design single phase. I suggest you contact the Works and inquire.
 

scout

New Website User
Non-VOC Member
scout

I did say OVER 30mph, it produces 2-4 amps. Much of the time , I am riding at 50-60 mph. Surely this should be enough to keep a battery charged. It was with the old, now defunct, Miller Dynamo.
The voltage across the battery does not get much above 12.2 volts with the engine revving briskly. How does this correspond with 2-3 amps showing on the ammeter. Is the Boyer regulator or the Alton at fault? How can I test either using a standard multimeter?
 

Howard

Well Known and Active Website User
VOC Member
I have a Comet with a Kirby Rowbotham electronic ignition, a Boyer regulator & a three phase Alton alternator fitted.
When the battery is showing over 12.2 volts everything runs very well.
Over a period of 50 or so miles the battery discharges to about 12.05 volts, despite the ammeter showing 2-3 amps over 30 mph in 4th. It then stalls & stops etc. This, with nothing other than the ignition working except occasional use of the stop light (LEDs)
The battery is nearly new & works well in an old Triumph m/c.

Anyone any idea where the current is going?

This is not my strong point, but it occurs to me that the ammeter reading is the difference between what's being made, and what's being used, not just what's being made. So according to your readings your alternator is giving you 2-3 amps more than you're using, but your good battery is going flat. That raises another problem I wouldn't consider 12.05 volts to be too low on a 12 volt battery, so perhaps your ignition isn't all it should be.

Check your wiring for anything using power that doesn't come from the ammeter, if your ignition (eg) is fed direct from the battery it may be using more than you're generating, but your ammeter could still show a 3 amp charge.

You could check for shorts by removing the earth lead from the battery, and checking for any discharge when everything is switched off, but you don't say the battery goes flat when standing, so that's not likely.

Check the current output from the regulator, if everything's going through the bike ammeter there should be a difference between this reading and the bike ammeter equal to what you're using.

As I said, I'm no expert, just trying to be an extra pair of eyes, sometimes we get tunnel vision with on-going problems.

I'd suspect the ignition. Let us know your findings.

H
 

timetraveller

Well Known and Active Website User
VOC Member
That is good advice from Howard except that I would disconnect the positive side of the battery, assuming that you have negative earth, and then with everything switched off see if there is 12 volts passing between the battery terminal and the positive lead. If there is then something is connected when you think that it is disconnected. I suspect that Howard's idea of the ignition current not going through the ammeter might be correct. When running the engine at enough revs to get a decent charge the voltage across the fully charged battery terminals should be 14.3 volts. If it is lower than that then either the battery or the charging system is u/s. A decent 12 volt battery will be at 12.9 volts after standing overnight having been run and fully charged the day before. If you have just come in from a run then the battery volts should be at 13+ volts.

If all else fails and you do not mind a non original look then why not fit one of our car alternator kits. They fit really well into the space on Comets where the rear cylinder would be on twins and they give a reliable 30 amps! :cool:
 

Pete Appleton

Well Known and Active Website User
VOC Member
VOC Forum Administrator
Charging tests

I wouldn't consider 12.05 volts to be too low on a 12 volt battery

Sorry to disagree but 12.05 V is what you would see from a totally flat battery. A well charged battery should show at least 12.7 Volts. I would suggest charging the battery with a charger and leaving it disconnected for a few hours and then check the battery voltage again to see if it has dropped.

The voltage across a fully charged battery with the engine running at a couple of thousand revs should be about 13.7 Volts. Anything less and you aren't charging.

Assuming that you aren't getting this 13.7 ish volts the next thing to do is perform the same test across the black & red leads from the regulator with the engine running and the battery connected. This will show up any broken wires or dodgy connections on the bike.

If all of the above still indicates that there is insufficient voltage coming from the regulator the next thing to do is test the internal diodes of the rectifier. This is easily done if you have a multimeter with diode check facility ( -|>| symbol on the dial). If not it is easy to make a tester with a light bulb and a battery. Perhaps it would be best to do the checks listed above and if you get to the stage of checking the rectifier let me know and I will give you a run through of how to do it.

Sorry to Time Traveller I have just noticed that he has already mentioned some of these points but he is a faster typist than me.

I fully support all disparaging remarks about the three phase Alton I threw mine away and fitted one of the kits that Time Traveller mentions. He is right that it looks far from original but the benefit is that you spend less time looking at the bike and more time riding it.

Pete
 

Howard

Well Known and Active Website User
VOC Member
No need to be sorry Pete. As I said, electricity not my field and I've never had a voltmeter on a bike, just seems strange, to a mechanical engineer, that a 12 volt battery needs to be at more than 12 volts.

With electrics I work on a process of eleimination, then take the (perceived) faulty bit to the experts.

H
 

Tom Gaynor

Well Known and Active Website User
VOC Member
Three-phase Altons

My three phase lasted longer than most, but eventually failed as they all seem to have done, and Paul Hamon reverted to the single phase. Mine was generously deemed still within warranty, so Paul sent me a new single phase (or if you prefer, a new old single phase) FOC. Unregulated it kicks out 31 volts AC, discovered while blaming the hardware for what turned out to be an occasional short from a severed wire) and I never think about it now. It balances a 55/60 headlamp at about 40 mph in top, and has done so for several thousand miles.
(I spotted the severed wire when I laid my head on the seat in despair of ever solving a mysterious electrical problem. Luckily I was looking towards the forks, and saw a wire where no wire should be. It was the live feed to the brake light switch on my front brake which had become trapped in the forks. It made me reconsider my dictum that there's nothing to be gained by giving way to despair.)
By the time it is dark enough to need headlamps up here it is too damned cold to ride, but it will balance gerbil heated gloves and headlamp at speeds low enough to avoid lethal wind-chill. Harder men than I, step forward Dick Sherwin, run headlamp and electrically heated everything (Y-fronts would be good) from a Sherwin/Walker car based unit, and have probably enough in hand to illuminate Coventry AND sell power to the national grid. Different strokes...
And to back up Pete, not that he needs it, fully charged my Yuasa BX14 or whatever shows 13.7 volts.

Sorry to disagree but 12.05 V is what you would see from a totally flat battery. A well charged battery should show at least 12.7 Volts. I would suggest charging the battery with a charger and leaving it disconnected for a few hours and then check the battery voltage again to see if it has dropped.

The voltage across a fully charged battery with the engine running at a couple of thousand revs should be about 13.7 Volts. Anything less and you aren't charging.

Assuming that you aren't getting this 13.7 ish volts the next thing to do is perform the same test across the black & red leads from the regulator with the engine running and the battery connected. This will show up any broken wires or dodgy connections on the bike.

If all of the above still indicates that there is insufficient voltage coming from the regulator the next thing to do is test the internal diodes of the rectifier. This is easily done if you have a multimeter with diode check facility ( -|>| symbol on the dial). If not it is easy to make a tester with a light bulb and a battery. Perhaps it would be best to do the checks listed above and if you get to the stage of checking the rectifier let me know and I will give you a run through of how to do it.

Sorry to Time Traveller I have just noticed that he has already mentioned some of these points but he is a faster typist than me.

I fully support all disparaging remarks about the three phase Alton I threw mine away and fitted one of the kits that Time Traveller mentions. He is right that it looks far from original but the benefit is that you spend less time looking at the bike and more time riding it.

Pete
 

rapcom

Well Known and Active Website User
VOC Member
No Y-Fronts

I haven't gone as far as heated Y-fronts yet, but my heated jacket liner (55W), heated gloves (15W), heated grips (15W), and heated SOCKS (another 15W) enable me to ride in comfort down to at least -5C.
One drawback is that I have to keep reminding myself that there may be ice on the road, it is easy to forget how cold it really is.
Originality ? I'd rather be warm.
 

timetraveller

Well Known and Active Website User
VOC Member
There I was on the beach in my sub tropical paradise, my every whim being catered for by scantily clad young ladies, all paid for by the profits from selling power to the national grid when Tom suddenly introduces a note of harsh reality into my reveries. I run a 120/90 headlight bulb and that take one third of the total power available. I also use coil ignition, have indicators (2 X 21 watts whenever they are working) and have a 21/5 watt tail light bulb. Others have intercom either to their passengers or to other bikes, some have satnavs. Some have sidecars with an extra headlight on the chair. All this before one has warmed ones bits and pieces. Ask the chaps who cross the Alps going from the heat of the plains to the ice of the mountains. Most of us do not use the 120 mph potential of our twins regularly but it is nice to know that it is there if needed. The same with the potential 30 amp output of the alternators. Modern regulators mean that no more is generated than is needed so power is not being wasted.

Must get back to the young ladies now!!:rolleyes:
 

Len Matthews

Well Known and Active Website User
VOC Member
I have a Comet with a Kirby Rowbotham electronic ignition, a Boyer regulator & a three phase Alton alternator fitted.
When the battery is showing over 12.2 volts everything runs very well.
Over a period of 50 or so miles the battery discharges to about 12.05 volts, despite the ammeter showing 2-3 amps over 30 mph in 4th. It then stalls & stops etc. This, with nothing other than the ignition working except occasional use of the stop light (LEDs)
The battery is nearly new & works well in an old Triumph m/c.

Anyone any idea where the current is going?

This tale sounds exactly the same as I experienced with a Comet. The owner complained of a flattened battery although the ammeter was showing a 2-3amp charge. Having no previous involvement with Altons, how does one distiguish a 3phase unit from a single phase one?:confused:
 

Prosper Keating

Well Known and Active Website User
Non-VOC Member
I have an early three-phase Alton that is still going strong on a bike that sees some respectable mileage. Even Hervé is surprised.

The battery will drain unless the revs are kept up but high cam engines are meant to spin rather than lug and I am currently running LEDs in the back and a car-rated halogen up front with a small-ish battery so I live with it. I did bin the electronic ignition as the advance curve was odd and resulted in vicious kickbacks. Now running a K1F with an ATD made up from the best bits from three knackered ones.

I gather that the new Alton spins more easily. Timing the motor with the old one is a bear-ish experience as the Alton's magnets are strong enough to turn the crank, pulling the piston away from the point BTDC. If my Alton didn't work, I'd probably just stick a 6v E3LM in there with a standard electro-magnetic CVC box. This set-up works on all my other bikes.

PK
 

scout

New Website User
Non-VOC Member
three phase alton

Thank you all for your help in this matter. This is my first post on the forum, & it has been most informative.
I have tried contacting Alton, but the factory is closed until late August.
I am not sure why these three phase Altons gave so much trouble, as alternators are fairly simple things. Is it not likely that the regulator packs up rather than the alternator or is there some known fault with the alternator which caused the reintroduction of the single phase version?
 

Tom Gaynor

Well Known and Active Website User
VOC Member
Low voltage and electronic ignition

Apparently the problem is that some electronic ignitions with electronic advance, Boyer Bransden being one, default to full advance when the voltage drops below 10 volts. As, for example, it does when cranking an electric start Norton Commando. What happens to a starter sprag clutch when the engine backfires? Nothing good.
Pazon ignition, set up by ex-BB guys, claims to have overcome this. If this information bears an astonishing similarity to information I absorbed from the Pazon website while looking for a system for a Sunbeam S7, it's just coincidence.

-
I am not sure, but think this is a quirk with electronic ignition when the battery voltage is a little low. My Vincent did it with Lucas Mistral, still does it with Pazon, and my old Commando does it with Boyer. Whether the ‘movement’ in the advance curve is also causing the wasted spark to have an effect, on a twin, I don’t know. I suppose it all depends by how much it moves and in which direction..........

If my bike hasn’t been run for a little while, I give the battery a charge before starting her up.
 

Pete Appleton

Well Known and Active Website User
VOC Member
VOC Forum Administrator
Alton Failure

is there some known fault with the alternator which caused the reintroduction of the single phase version?

My first Alton failure occured at 1000 miles and was due to the nylon gear in the cyclic gearbox shedding all of it's teeth ( a number of people have suffered from this). I think that this was due to excessively thick grease sticking around the inside of the gear housing and not flowing back into the gears.

I replaced the gear and put in 'OOO' weight grease from truck chassis lube systems. This worked ok for another 6000 miles until the windings fried themselves.

I haven't heard of a regulator failing unless it has been subject to a short circuit or reversed polarity.

Unfortunately inability to communicate with the manufacturer seems to be a common problem
 

Alan J

Well Known and Active Website User
VOC Member
Some interesting comments here {I've been away again on another long holiday} I'll stick with my 12 volt Lucas car dynamo that has served me well for 30 years-more watts than I will ever need! Mr. Sherwin has the best system if you don't mind it not looking original-this topic is never ending!:confused::confused::confused::confused:
 

Top