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#860501 10/11/21 1:24 pm
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RicLand Offline OP
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I have a 1960 Gold Star which can be shut off with the compression release lever as is normally done. However, I wonder if there's a way to install an electric kill button in addition. The bike is equipped with a road going magdyno, not the racing mag which has the external post for a kill wire. It also has a solid state regulator, not the original points Lucas unit. Any thoughts or recommendations for this additional install or should I just be content with pulling the lever for stopping the engine?
TIA
Ric

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RicLand #860527 10/11/21 9:03 pm
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Hi Ric,
There are at leas two companies that sell a magdyno end cap that is usually used in conjunction with an oil cut off tap that prevents the bike starting without the oil tap turned on. It can be used as an ignition cut out on its own
here is a link to one of them, https://shop.kingpincomponents.co.uk/points-caps

John

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John,
Thank you, this is exactly what I was looking for. I suspected that grounding the points would kill the spark thus stopping the engine. However, I'd like to find a US supplier/manufacturer to make it easier for me to get the Kingpin style cap (plastic version since clearance is an issue)--shipping, payment (no cc), time are always a deterrent for me. If I can't locate a US seller then of course I'll order from the company you suggested. Is the second supplier also in the UK, the US or other?
Again, many thanks for your help in my search. Aside from the instant response the kill button affords there's also the benefit of no strain on the exhaust valve train caused by pulling the compression lever on a running engine, whereas I don't suppose there's any bad side effect in shorting the points--or is there, to the mag?
Ric

RicLand #860630 10/12/21 9:02 pm
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Hi Ric,
The other company (magneto guys?) is also in UK
Shorting the points is standard on K1F and K2F Lucas mags also BTH and many more
It is also a further safety device if the throttle sticks open
It can also be wired to a hidden switch with the other side grounded as an additional security device

John

chaterlea25 #860643 10/12/21 10:57 pm
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I wonder if there's a straightforward way to simply ground the points, to a switch as you suggest, that I can hide somewhere near the handlebars. I remember doing it on my doodlebug lawnmower engine when I was a young(er) delinquent.
Hopefully someone on this forum has already done it on their Goldie and they can chime in with a schematic or an easy to follow drawing. Fingers crossed. LOL.
Ric

RicLand #860653 10/13/21 1:15 am
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Originally Posted by RicLand
I wonder if there's a straightforward way to simply ground the points,... a schematic or an easy to follow drawing.
The caps shown in the link in chaterlea25's earlier post rub a pickup against the points and bring that connection to the outside of the cap. All you do is run a wire from that connection to a switch on the handlebars. When the switch is pressed and makes contact with the handlebars, the spark will cease.

If you pinch the wire on the way to the handlebars, you can accidentally ground it at that point. If the switch itself is defective, or is of a "normally-closed" type rather than "normally open, again you will ground the magneto. So, it's really as simple as a wire from that cap to a switch on the handlebars, but there still are opportunities to screw up.

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Magnetoman,
I get everything except "rub a pickup against the points." Can you elaborate/elucidate? None of the pics of the likeliest cap (Code MO1NC) shows the reverse side and so hiding whatever connection is made between the points (which one?) and the exterior post. Wouldn't a simple wire connected to either the moving points arm or the stationery one do the trick--by that I mean grounding the connected wire through a switch or a kill button, the "spark will cease" as you put it? I'd like to know which part of the points the wire is connected to.
Ric

RicLand #860658 10/13/21 3:09 am
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The portion of the points that needs to be grounded is the rotating bolt in the center so it needs a contact that rubs against it, not wired to it. The inside of all those caps looks like the K2F. A carbon brush is pushed against that rotating bolt by the springy bent blade that in turn is connected to the post on the outside of the cap. Lucas made their own back in the day, using a spring to push the carbon brush.

Oops, you have a magdyno so the construction of the rotating points is different than a K2F magneto. However, the principle is the same. You need to make contact with a rotating surface

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Originally Posted by Magnetoman
Oops, you have a magdyno so the construction of the rotating points is different than a K2F magneto. However, the principle is the same. You need to make contact with a rotating surface
On the MO1, the grounding brush would be making contact with the spring steel arm that carries the "non fixed" breaker point.

Ric, why don't you pop that little steel points cover off your magdyno and have a look inside. That could clear up some of this mumbo-jumbo we're trying to communicate.

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Originally Posted by Stuart Kirk
Originally Posted by Magnetoman
Oops, you have a magdyno so the construction of the rotating points is different than a K2F magneto. However, the principle is the same. You need to make contact with a rotating surface
On the MO1, the grounding brush would be making contact with the spring steel arm that carries the "non fixed" breaker point.

Ric, why don't you pop that little steel points cover off your magdyno and have a look inside. That could clear up some of this mumbo-jumbo we're trying to communicate.

I don’t see how you can have an old bike and never have seen the points.

It is possible to run a carbon brush against the moving point arm of a face-cam magneto. I’ve done it.

Not saying it’s great engineering, because the brush has to move in and out a little with the arm, but it can work.


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Hold on there feller! Not only have I SEEN the points, I've also adjusted them several times, I've set the timing (pulled the mag pinion), installed/adjusted the carb, installed/adjusted Phil Pearson clutch and so on and so forth. All I'm now trying to accomplish at this juncture is to install a kill button on a machine with a magdyno, a device with which--admittedly--I am not familiar. If someone else on this forum has done it previously and met with success, then I'd hoped to learn from them. If I'm just being a nervous nellie in having to have a second way of stopping the engine(compression lever plus kill button), so be it. I'll just order one of the aftermarket KINGPIN caps and call it good. No disrespect to anyone, on the contrary, I truly appreciate the constructive & instructive comments received thus far.
Ric

RicLand #860704 10/13/21 8:37 pm
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Originally Posted by RicLand
.......No disrespect to anyone, on the contrary, I truly appreciate the constructive & instructive comments received thus far.
Ric

One of the problems with a forum like this one is the wide differences in experience, communication skills and dare I say this, patience? Sometimes it's hard to know where to start or how to proceed, all part of communication. But all that aside, we folks manage to help each other out a lot of the time though it might take a little while to get there.

Myself, I've never worried one bit shutting down my Gold Stars with the compression release, or any of my unit singles for that matter. It's interesting to note just how many more wheezes it takes for a Goldie to roll to a stop compared to a unit single with its lighter flywheels.

Metal kill buttons on mags have been known to shock you if you're not wearing gloves. I find that a bit annoying so personally, I wouldn't go out of my way to put one on my bike unless there was a really good reason..

I'm interested to see how all this works out for you.

RicLand #860712 10/13/21 9:11 pm
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Yes hundreds of volts reach a mag kill button. You can’t use a bit of hacksaw blade unless your gloves are never wet!


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RicLand #860713 10/13/21 10:14 pm
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As for ways to stop an engine, the more, the merrier. However, for what it's worth, I only have one way -- the lifter -- on my Gold Stars. When starting the bike, pulling on the lever forces a "cam" to push down on the rocker, acting against the force of the valve spring, to open the exhaust valve. However, when stopping the engine, the pushrod provides the force to open the exhaust valve every half-second (300 rpm/60sec/min./2 revs = 2.5 openings/sec) so pulling on the lever just moves the "cam" into place to keep the pre-opened valve from closing, with less strain on the components than when the engine was started.

A further advantage of the lifter is there are no pesky carbon brushes, wires, contacts, or switches, ready to cause problems when least wanted or expected. Also, you would be relying on the design and reliability of an aftermarket-engineered electrical component (the magneto cap) to do the job, which is something I personally try very hard to avoid.

[Linked Image]

Again, for what it's worth, the only valid reason I can see adding for adding an additional electrical component to the magneto is if an anti-sumping valve is fitted and you were concerned you might forget to open that valve. My BB Gold Star came with such a valve fitted, which concerned me at the time, so I bought a replacement valve with a switch with the intention of tying it to the magneto. However, the aftermarket valve/switch was such an amateurish bodge that I kept it, rather than return it, to serve as a reminder why it is dangerous to trust aftermarket-engineered parts for "mission-critical" tasks. Instead of making my own valve/switch I decided I should just remember to open the valve. Which, thus far, I have (fingers crossed)...

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Magnetoman et al:
Thank you for taking the time to comment and to share your experiences related to my opening query, ie., how to install an electrical kill switch on a magdyno equipped Gold Star. I've learned quite a lot reading your advice and have come to understand the pros and cons of such an undertaking: it is more involved than I'd anticipated, perhaps also riskier (electrical shock), maybe unreliable in the long term, and--more importantly--unnecessary since the compression release in theory and practice works well. Lastly, my initial fear that using the compression release might place undue stress on the valve train has turned out to be unfounded. I'm glad to move on to other aspects of maintenance and care of one of my favorite motos.
Again, thank you all.
Ric

RicLand #860848 10/15/21 9:35 pm
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One final thought to all of this, somewhat related to be sure but, without a hidden or otherwise located ON/OFF switch, how do you all keep your Goldies from being stolen when left parked, out of sight, while in a cafe or tavern or an establishment that draws you in? No lock, no switch, no nothing?
Just sayin'
Ric

RicLand #860855 10/15/21 11:40 pm
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Kick through to free up clutch plates, retard the ignition by not-too-much, not-too-little, activate choke, tickle the carburetor, push the piston to near TDC, pull in compression release, ease piston to just past TDC (but not much further than that), and give it a firm kick. If someone has mastered that it seems likely he can master the art of cutting the wire to the magneto cap.

RicLand #860869 10/16/21 8:16 am
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Originally Posted by RicLand
One final thought to all of this, somewhat related to be sure but, without a hidden or otherwise located ON/OFF switch, how do you all keep your Goldies from being stolen when left parked, out of sight, while in a cafe or tavern or an establishment that draws you in? No lock, no switch, no nothing?
Just sayin'
Ric


I chain the bike to something solid.


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RicLand #860894 10/16/21 4:39 pm
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I locked my Ariel in our support truck every night of the Cannonball. Although many lunch stops were at Harley dealers, where it was surrounded by other bikes and hundreds of people, at least a dozen times over the two weeks I parked it for the better part of an hour, unlocked and where I couldn't see it.

[Linked Image]

If parking a magneto-equipped bike unlocked has a risk factor of 10, just about any chain or lock might drop that to as low as 5 (or, it still could be 10, depending on the neighborhood). However, I'd say that if having a keyed switch that shorts the magneto end cap to earth is the only deterrent, the risk factor is 9.9. Or, 11, if it makes you think that switch makes it safe to park somewhere that is especially risky.

For what it's worth, I'm more concerned with a couple of guys loading a bike in a pickup than I am with someone starting one of my old magneto-equipped bikes and riding off. If I'm at a motel where the bike has to be outside I park it where it has the least visibility possible and use a Kryptonite lock. When we rode two Gold Stars across Texas I Kryptonited the two together. However, someone with a battery-powered angle grinder could deal with a lock or chain in 15 seconds, or deal silently with a chain using bolt cutters, and two guys wouldn't even have to remove the lock to wrestle a single locked bike into the back of a truck.

Last edited by Magnetoman; 10/16/21 5:40 pm.

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