Points and coil questions

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Apr 2, 2008
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I am still satisfactorly running points in my 850 Mk I. I need to buy a replacement set of points and understand that it is not always easy to find good quality Commando points these days. Any ideas for a good source or brand of good points.

Regarding coils, right now I am running 2 stock Lucas 6 volts. One was sort of crushed (but still operating) at some point in its life so if I were to replace them is there any advantage (either spacewise or performance wise) going to a dual output 12 volt coil?
I'll be interested to see where you go here. I'm thinking of converting my Boyer equipped Norton to a pair of Ford six volt coils like I used to run years ago. I also have a bunch of Honda coils around but they don't put out much more than a Norton.
I ran a pair of Ford 6V coils on my '72 with a Boyer for years. This was the big craze after Gordon Jennings article in Cycle. K-Mart coils were supposed to be the "hottest" but I got mine in the local help yourself junkyard.
Thanks a lot! I didn't know they would run ok with a Boyer for sure, but now I do! Did you use a resistor? The Ford coils lasted me somewhere like from 1972 to when I gave the bike away which was probably around 1984. My wife would remember I'm sure.
Cookie -

The Boyer instructions have you eliminate the stock ballast resistor. The Boyer MkIII wants to ideally see 3-6 ohms (3 ohms recommended minimum in the instructions) so it wouldn't be a bad idea to measure the new coils to make sure you are in the ballpark. The Ford 6v coils are wired in series just like the stock 6v coils so the resistances add.

At the time I did measure the current to make sure the Boyer wouldn't fry and it was not much different than the stock setup. Starting was a lot better than with the stock Lucas coils. I ran this setup for years and then decided I wanted to go back to a cleaner look so I switched to an Accel then a Dyna black dual tower coil mounted just behind the stock coil bracket. These are pretty much equivalent functionally. The Accel is yellow and matched my yellow bike at the time but then I went to an orange tank and sidecovers and the colors clashed... :lol:

I hope I didn't just buy some coils with too much resistance. Back to you later on this when they get here. That's the problem with Ebay is you don't see it until later.
I still have my Ford coils somewhere out in the garage. When I get home tonite I will measure them and see what exactly I had there. They may have been 12V coils for all I know. (But they worked!) Back before the internet things were not as well-defined!

It was a hot summer day in the junkyard when I got them and a couple times I had to run from the yellow jackets that had made nests under some of the car hoods (bonnets for those in UK!) It was a good thing I was a lot younger then. The junkyard guys had a good laugh though.

It was a good thing I was a lot younger then

You had already dated yourself when you mentioned a "help yourself junkyard". :shock:

The liability lawyers ran those out of business decades ago! :lol:
I'm glad to see that there are some younger Norton owners out there to back up those of us who were around to buy them new.
Ron - The junkyard is still there and still help yourself as far as I know. (They usually will check your toolbox on the way out if you look guilty.) It is only about 3 miles from where I live in the boondocks. I think everyone who works there is a Harley rider. Usually there is a nice lineup outside in the summer months but it is on a road that few people ever need to go on for anything.

Cookie - The coils I used ARE marked 12V and the resistance is 1.4 ohms each on my Fluke 29 meter with low ohms range, so they are just below the edge at 2.8 ohms in series. A 1-2 ohm ballast resistor would be safer but I had no trouble using them just as-is.

See http://www.hot-spark.com/HS13BR.htm

For those who don't know, the Ford coils are nice because they are short for an automotive coil and the Ford brackets can be used as-is under the screws that hold the old coils. They just make it below the tank but they are much fatter than the original coils. The bracket has to be bent down just a tiny bit to clear the tank. They do put out a great spark. I was able to open my plug gaps to 35 thousandths.

It is just one way to go. I like my dual tower coil better just because it works as well and is less bulky. With the Taylor headsteady it really opens up the space around the engine under the tank.

I've ordered some high performance coils that are supposed to fit the Ford brackets.
The problem with internet stuff of course, is that you can't really see and measure it first. I hope I didn't just waste a hundred bucks.

By the way the specs on the coils I ordered say 0.6 primary resistance so I should be fine with a resistor I'd think. That seems pretty low to me for a high performance coil.
Thanks for taking the time to look those up. I have a Chrysler resistor in the garage as well as a couple of Honda ones so I'm sure I can add resistance if needed.
I'm pretty sure in the old days I just used two Ford six volts and a Chrysler resistor. I did use them with points and as you say the Ford bracket was bolt on. That gave a nice hot spark and really improved cold starting.
The coils and resistor package I want to use measure 6.2 ohms. I'm hoping that's close enough to the ballpark.
Can we get more specific on these Ford and Chrysler parts so we know how to duplicate some of this?

Also, what about a source for the points themselves? The set of points on Ebay had a different part number than given in the part book for the 850.
I'm trying something new so let's see if it works first before someone duplicates my errors. I'm a bit sick today but I'll install and test this weekend.
The ones I know I used to run were six volt Ford coils, look up a 54 Ford customliner V8 as an example for that. For the 12 volt Ford coil ask for a 65 Ford V8.
For the Chrysler type resistor I used to use and will again try a Niehoff
AL 125K.
This is what I'm going to try on my bike.

This is comparable to hitting a bug with a sledge hammer. I know these work on BMWs and the stainless case looks good for a long time, the size isn't all that bad, and they are epoxy filled. If I ever brush a plug wire it will be like getting hit with a Taser.
I haven't finished the installation yet. While I had the bike apart I decided to rewire. I may test it today.
I had time to test the basic unit yesterday for spark. The coils are working with the Boyer unit. I plan to test it without the resistor to see what happens there.
After bypassing the resistor I got the large blue spark I wanted. these are 12 volt coils and seem to want the entire 12 volts. Apparently the Boyer will fire these on the resistance they have.
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