Starter mods, upgrades

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Mar 6, 2007
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As mentioned a few weeks ago, I buggered my starter motor beyond repair. As my right knee is playing up I'm keen to get back to starting on the button as it worked very well up to that point, so if anyone has a standard motor for sale please let me know, even one in need of repair. Alternatively I've heard people refer often to the use of Harley type starters but have no idea how it's done nor of exactly which parts are needed. Can anyone point me in the right direction here please? I'm looking for detailed instructions or perhaps a link to any previously published articles about how it's done. I don't mind a wee bit of machining/modification as I have a lathe and mill etc, so a reasonable amount of work won't put me off.
thanks in advance
millard
 

L.A.B.

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millard said:
Alternatively I've heard people refer often to the use of Harley type starters but have no idea how it's done nor of exactly which parts are needed. Can anyone point me in the right direction here please?

I believe that it is possible to fit the field coils and brush holder from a Harley Prestolite starter to the Norton one which would upgrade it as the Norton starter only has two field coils (and two brushes) however I don't think that the Harley armature can be used (at least not without some modification)?

Harley starter
http://www.dansmc.com/hd_xr_starter.JPG



millard said:
I'm looking for detailed instructions or perhaps a link to any previously published articles about how it's done.

Here are some previous forum threads on the subject:

http://www.accessnorton.com/norton_commando1228.html

http://www.accessnorton.com/norton_commando1103.html

http://www.accessnorton.com/norton_commando970.html

Have you thought about buying the Norvil (Dave Comeau) starter?
http://www.norvilmotorcycle.co.uk/064791B.htm

CNW also sells a replacement upgraded starter:
http://www.coloradonortonworks.com/cata ... sp#starter
 

Ron Hulton

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You need to get a set of high torque field coils from Accel .. P/N 40115 and a 4 brush kit.. I believe my cost Canadian was about $90 for the parts.. I also switched to a Deka absorbed glass mat battery which was $114 Cdn..

If you would like to contact me with an e-mail address i will send you a diagram and complete instructions on how to make this work.. My suggestion though is to have someone in the starter business do the job for you .. Believe me , there is just enough room in a Norton starter case .. To use the Harley case you will need to machine a spacer / adapter so the Norton drive end cap will fit the Harley case .. Really not worth the hassle in my opinion

To say that i am happy with the performance of this starter is an understatement .. It starts my bike as fast if not faster then any modern bike going.. Before i can get the starter button pushed all the way in the bike is going.. Might also have something to do with a no nonsense Mikuni carb too

Cheers
Ron
 

L.A.B.

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The four brush plate conversion is available from RGM Motors in the UK, and with heavier duty starter leads and an AGM battery (I believe Millard is already using an Odyssey AGM?) I find that is also more than adequate, even without the four field coil kit. I'm now using a Westco battery instead of an Odyssey as it has a higher CCA output, as I personally believe the weak link in the original system was the battery and not the starter motor.
 
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Les/Ron
Thanks both of you for all of that. I think I know what's required in terms of parts now for the HD conversion.
just to clarify things, here's what I had before

Standard Commando starter but with the RGM 4 brush conversion. standard cable and Odeyssey battery.
It worked great, until I shagged it :x :(
I could get the Dave Comeau one from Norvil but at £275 it seems a bit steep. I might get in touch with Mr Comeau and see what it would cost to ship one direct to UK.
I did fancy trying to do it on the cheap as my shed budget is being severly curtailed for the coming year due to building extension etc etc etc.

So that's why the HD route seemed attractive.

Here's what I have left.
1 The standard armature.
I don't know if this could be rewound or if it's beyond redemption, any body know from these pics if it could be rewound?

http://i193.photobucket.com/albums/z258 ... C05624.jpg

http://i193.photobucket.com/albums/z258 ... C05623.jpg

http://i193.photobucket.com/albums/z258 ... C05622.jpg

http://i193.photobucket.com/albums/z258 ... C05621.jpg


2 The standard starter body with at least one of the coils damaged. It's back on the bike now acting as an oil plug for the primary so can't take a pic easily.

3 The RGM 4 brush end plate which I think I could save.

So Ron, perhaps you'd be good enough to send your instructions please? I'm curious as to whether you removed the coils yourself and if so how? I always understood these were virtually impossible for mere mortals to unscrew, then if this could be achieved that they had to be done up again incredibly tight.
email address millardp@ntlworld.com

So going for the cheapskate option I need to figure out if it's cheaper to get new coils fitted to the existing body or try to scource a used HD motor to modify.
Whatever happens I reckon finding a Commando armature will be a wee bit dificult so I'll see if I can get the buggerd one repaired.

Thanks again.
BTW Les, how do you get the "search" function to work?
I punched in Starter/motor/upgrades and all sorts of variations on that theme and kept getting reams of posts bearing no relation to starter motors :?

cheers
millard
 

L.A.B.

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millard said:
BTW Les, how do you get the "search" function to work?
I punched in Starter/motor/upgrades and all sorts of variations on that theme and kept getting reams of posts bearing no relation to starter motors

I think I searched for = *Harley* and *field coil*. I then had to go back a few pages to find the actual topic headings.

(= Norton 850 Commando Starter Alternative.)

(= Prestolite Starter)

(= MK III starter motor 4 field coil, 4 brush upgrade)
 
Joined
May 22, 2005
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Hi Millard
I’ve not been on the board for a week or so, and I’ve only just caught up with your thread.
I have a standard two brush Prestolite starter in full working order that’s available if you are interested.
I upgraded to a Dave Comeau starter about eight months ago, it’s brilliant and well worth the money, and I only use the kick starter now to put the engine onto compression before I park the bike in the garage.
My own experiences may be helpful to you whichever starter you eventually use.
Firstly fit up rated leads Norvil part no’s 065909, 065910 and 065911.
The standard leads aren’t really capable of carrying enough current and cause quite a bit of voltage drop at the starter motor.
Secondly replace the gear wheel and engine sprocket as well as the sprag. They are part no’s 064681 & 064781.
If you don’t the new sprag won’t last very long, don’t ask me how I know!! Les at Norvil recommends this anyway and I can assure you it’s not just to increase his profits.
Thirdly consider changing your ignition system from Boyer to one of the modern units that aren’t voltage sensitive, I changed to the pazon analogue unit and I’m very happy with it, it was the Boyer fully advancing and the engine kicking back while I was using the Prestolite starter that destroyed the sprag clutch and led me to do all the upgrading work in the first place.
As far as being able to tell which way the sprag is fitted the workshop manual says fit it with the sprags facing forward, but with the newer type sprag it’s a job to tell if it’s right or not, so to be sure I fitted the primary chain, sprocket and clutch drum to the bike.
I then fitted the sprag into the crankshaft sprocket followed temporally by the gear wheel (part no 064731) as you face the bike the gear wheel should rotate freely backwards (clockwise) but attempt to turn the engine over if you turn it forwards (anti clock wise)
I did it that way and my starter works perfectly.
I hope this helps and if you are interested in the starter motor let me know.
 
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Hi Millard,
You said you'd pm'd me, but I haven't received anything. Could you try again, please?
I'm a truck driver and sometimes don't get home at night, so it might be a couple of days before I can get back to you.
Regards, Mike
 
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Mike
Sorry but my email's playing up badly at the moment. I thought it was just mail getting in but looks like it's two way.
I've just resent.
cheers
millard
 
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Well I decided to go the cheapskate route and attempt to modify a Harley version of the Prestolite starter, so I took my knackered armature to local motor rewinder and they said it couldn't be done. Never one to accept unwelcome news readily I tried a second opinion. They said it could be done but that the nos armature on ebay from Oz for £100 including postage would be a cheaper option. So I took the "buy it now" option and started looking round for a body with decent useable coils to modify.
Then sod's law came into full force and Mike (mikeymike552001) read the thread and offered me his used but good starter for a very reasonable price. It arrived just before the Oz armature.
Ho hum.
Why do the words "raining" and "pouring" come to mind?
So I set to and modified Mike's starter to a four brush configuration. I put it on the bike with the plugs removed and the primary chaincase off as I was replacing the crossover shaft seal at the same time.
I wanted to be sure that I didn't have a repetition of the wee incident which shagged my original by it running in reverse. It turned the engine over ok with the plugs out and then briefly with them replaced, but when I came to start it and check things out with the motor running it only gave a click at the solenoid. Puzzled and anxious I set about removing it for a check of my internal wiring, but then I realised just how hot the original starter leads get. I'd never noticed this before, pêrhaps because I'd never had cause to go near the starter since I did the original 4 brush conversion. Anyway all was well internally so I reckoned it was just a flat battery and maybe starter leads not tight enough.
So I put the Odyessy on charge overnight and made up a set of heavy duty leads this morning and it whizzed round quite happily. So far it's looking like a happy ending, but I have a minor doubt now.
I started the engine briefly a couple of times to check the starter motor wouldn't run in reverse. What I found was that the motor and it's assocciated gears turn for a brief while after I release the starter button, not for very long, maybe less than a second or so, but it is noticeable.
Is this just the motor running down from it's operating speed? or should it stop more or less instantly? Am I worying about nothing here?
Second, and perhaps more worrying is that when switched off, the engine goes maybe half a turn or so in reverse. I think it's coming up against compression then kicking back a wee bit. Probably normal? but I can't see if the anti backfire device is working to prevent the starter from reversing or not, as I'm trying to manipulate the starter switch and the ignition key by myself and and can't get down low enough to see the starter gears. I can see that the backfire device gearwheel turns in reverse but can't see if it's "clutch" mechanism is working to disengage the drive to the starter or not. I know the starter gears are not turning when the motor is actually running as I can let go of the switch gear and get down to look into the primary but again, am I worrying unecessarily?

BTW
The "Mystery oil leak" thread was very useful!!! geuss what I'm doing next?

cheers
millard
 

L.A.B.

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millard said:
What I found was that the motor and it's assocciated gears turn for a brief while after I release the starter button, not for very long, maybe less than a second or so, but it is noticeable.
Is this just the motor running down from it's operating speed? or should it stop more or less instantly? Am I worying about nothing here?

I'm sure you are worrying unnecessarily, as the starter motor will need to run down for a second or so after the button is released (I think I would be more concerned if it didn't).


millard said:
Second, and perhaps more worrying is that when switched off, the engine goes maybe half a turn or so in reverse. I think it's coming up against compression then kicking back a wee bit. Probably normal? but I can't see if the anti backfire device is working to prevent the starter from reversing or not, as I'm trying to manipulate the starter switch and the ignition key by myself and and can't get down low enough to see the starter gears. I can see that the backfire device gearwheel turns in reverse but can't see if it's "clutch" mechanism is working to disengage the drive to the starter or not. I know the starter gears are not turning when the motor is actually running as I can let go of the switch gear and get down to look into the primary but again, am I worrying unecessarily?

Again I do not think you have a problem, as I would consider it normal for the starter mechanism to be motored backwards by compression as the engine stops and the crank rolls backwards, this will cause the sprag to engage momentarily, and I've known many other bike starter clutches of this type to do it.

Do not expect the anti-backfire device to work if this occurs as it should only slip if the crankshaft is kicked backwards (or brought to an abrupt halt) while the drive gears are under power from the starter motor. The A/B clutch has no slip bias as to the direction of rotation (it does not slip easier in one direction than in the other) so will only slip if the starter drive gear becomes overloaded as I described (if it is adjusted correctly?).
 
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OK thanks Les, I was a bit concerned about making another expensive mistake but you've put my mind at rest.
I'll throw it all together again then.
Cheers
millard
 
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May 22, 2005
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Hello again Millard
Glad you were able to modify my old starter motor; I assume you found the missing washer ok!!
I can confirm every thing that you’re experiencing with the starter gearing seems to be normal; mine operates in the same way; in fact if there wasn’t any tendency for it to “run on” a bit when the starter button is released I would be concerned that something was binding somewhere.
Did you replace the crankshaft sprocket and gear wheel at the same time as the sprag? I didn’t when I did the job the first time and within three months the new sprag had started to fail; sometimes not engaging when the button was pressed or at other times the sprag would fly out of engagement while the engine was turning over making the most horrendous banging and crunching noises.
It seems that there only needs to be comparatively slight wear on the surfaces that the sprag drives on to stop it working properly, (mine had very slight craters in the surfaces where the original sprag had been engaging)
Replacing all three components cured the problem but it was annoying to have to strip everything down and do the job all over again.
That’s my ten pence worth anyway.
By the way have you seen this on eBay today?
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... &rd=1&rd=1

Regards Mike
 
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Mike
No I never found the dished washer form your starter. I did eventually track down the one from mine. I reckon it's the lost sock syndrome coming into play, y'know all those odd socks you get from the washin machine? Where the hell do all the missing ones go? This is the second time I've lost something from the Commando in the shed and not been able to track it down. I still don't have a kill switch coz the internals from the right hand switch gear went flying accross the shed when I stripped it. I know which corner of of the shed they went to but still couldn't find them. If anyone's got a spare ball and spring from the kill switch contacts please get in touch!
Interesting price on that Ebay starter eh? Think I owe you a pint if we ever meet. Thanks :D
Thanks for your feedback, you confirmed what Les said.
I didn't replace the sprag as it was working before all this happened, but I'm now begining to wonder.
Here's the story from the begining.
I stripped the primary to fit a Sparx high output alternator. Previous to that the starter was working strong and perfectly every time.
When I put it all back the starter was ruined when I started the engine. I thought at the time it was due to the A/B device not disengaging but as I think more about it I realise it was more mikely due to the crank gear being driven by the sprag and running the starter gear when it should freewheel due to the one way action of the sprag.
BTW I've been refering to the starter being run in reverse but really what I meant was that the engine is driving the starter instead of the other way around, it still runs the same way, just much faster than intended. This I reckon was what destroyed my starter. Late yesterday I reassembled and noticed that when firing her up and keeping her just on tickover (being careful not to rev her up) that the crank was driving the entire starter gear train. I had been playing around with the nut on the A/B "clutch" as it was at first slipping when I tried to start the motor. Eventually after tightening a little at a time it started, but the whole lot then was driven, as I said from the crank gear which means that the sprag isn't dissengaging. But how can this happen?
Back to the drawing board today, I'm gonna strip it down to the sprag and have a good look.
Bugga!!!
millard
 

L.A.B.

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I suggest that you inspect the sprag cages carefully for cracks, and the internal leaf spring even more so, as the tags can break off, this could possibly cause the sprags to hang up?

If the assembly (sprag/gear/engine sprocket) is worn then the sprags could possibly roll too far and 'lock on' until the crankshaft rotates fast enough to throw them back?

If it is the old 14 element sprag unit I (personally) would not want to re-use it.

One thing that could possibly be causing the sprag to stay engaged is that you will be doing all this checking with the primary cover removed to observe what is happening? So the sprag is probably dunning 'dry' or at least not receiving the amount of lubrication that it would if the cover was on and the chaincase oil was present, so that may be causing it to stick?

(a lot of 'possibly's in there I know)
 
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Hi Millard
I was busy composing a reply to your last message when labs came in.
I agree with every thing he says, I was never able to inspect my old fourteen element sprag as I ended up hoovering the shrapnel out of the primary chain case!!
I do however know that its replacement failed because the inner brassy coloured leaf spring had started to break up possibly because the sprags were moving too far because of wear on the sprocket and gearwheel components.
The other thing that might well be worth checking is that the needle roller bearing inside the gear wheel is in good order, if that was worn or partly seized it might just create enough friction to rotate the starter assembly.
On balance though; and in view of all the work you’ve done already I’d be inclined to bite the bullet and replace the engine sprocket, sprag and gear wheel, expensive I know but so is the risk of damage to another starter motor
By the way I agree with what you say about the sock syndrome; I was changing some shock absorbers yesterday evening and as I pulled one off its top mounting the spacer that was fitted behind it came off too.
I SAW it come off, I SAW it hit the ground but could I find it; could I xxxx! The replacement only cost just over a pound but it was just a time wasting nuisance to have to go into town to buy it.
 
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Mar 6, 2007
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Well I've just come back from a wee test ride and it's starting and running nicely now. Think I'll take your suggestions on board though and order the updated sprag and new parts to go with it.
Thanks for all the helpful suggestions, and to Mike for the starter.
cheers
millard
 
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