View Full Version : 1973 Ironhead Sportster runnin' early mag?

30th December 2004, 16:31
Hey guys! I'm new to the forum but not to Sportsters. I've always been a big fan of the smaller Harley! I have a '98 Evo as a daily rider and a '52 K and a '73 ironhead as well.

My question is, I have an old Fairbanks Morse magneto that mounts to the top of the timing cover on the old K-model. That mounting boss isn't there on the '73 ironhead and I was wondering if I could just use an earlier ironhead or K-model timing cover in order to use this mag? Is that possible? Are there aftermarket covers that would allow me to do this? Any and all help appreciated!

Sportsters Rule!


30th December 2004, 16:35
I'n not sure if an older cover will work....... I think they have differant gears in side for driving the mag

but don't quote me on that , I'll see what I can dig up

30th December 2004, 16:47
Hey T-Bone, welcome to the forum. I'm sure the Ironhead contingent is happy to have yet another supporter. Make sure to start a thread in the "Introduce Yourself" section so everyone has a chance to meet you. Glad to have you aboard.

30th December 2004, 17:23
Flathead 45,

Thanks for the response. I have my K-model apart for a full rebuild, so I'm familiar with the cam and gear arrangement on it, but, I've never had the timing side apart on an ironhead. That's where I was hoping someone would know more about it. Thanks for your input. I really didn't want to tear into a perfectly good runnin' ironhead only to find out it's not possible. I like the idea of strippin' all of the electrics off of this thing and just runnin' a mag, battery eliminator and the basic lighting. I'm really wantin' to strip this bike down to bare bones, ya know?

Red Rider,

Thanks for the welcome! I will take your advice and welcome myself as you suggested.


30th December 2004, 17:27
do you have the book on the 73 ? if so you can compare the gears from the "K" to the "FE" that might give you some insight as to if the swap is possible

I might be shooting at stars here but would it work down the tach drive hole?

30th December 2004, 17:48
No, I don't have the book on the '73. I just got it. I had a '73 before and rebuilt the top end on it, but I had to sell it to buy my house. Really bummed me out! Anyway, I've got a couple mannuals for the Evo and one for the K, but don't have one for the ironhead yet. I'll score one on Ebay and do as you suggested. I just thought maybe someone here had done it our knew if it was at least possible.

Thanks again for your input.


31st December 2004, 03:07
Hello T-Bone.....Yes, you can use the cam cover from the earlier mag cover Sporty motors, but you will also have to use a set of early cam gears along with the early cover. The early cam gears has the appropriate gear to drive the magneto. You will have to shim your cams as per the early manual. I think you can use the needle bearings in the later motor...but not sure...might have to press in a set of early ones also. I would also press in and ream a new set of cam bushes on the cover.
You can save yourself a lot of trouble by contacting Joe Hunt Magnetos....They manufacture a Magneto that drops into the 73's cover where the tachometer cable connects. I believe the cost is about $800 for the new mag. Sounds a little expensive, but if you consider the cost of a a good early cover, an equally good set of early cams or new ones, plus you would probably want to replace the cam bushing in the old cover...your probably in for a good $500.00....unless you have the parts already sitting on the shelf?....so what a couple hun more....Only drawback is you loose the use of your stock mechanical tach and will have to get a electronic one....(unless Joe Hunt has upgraded the magneto to accept a tach drive cable).....Not sure about that....I haven't gone on his site in a few months.
Joe hunt has been building the best Magnetos since WWII....Had one on my 68XLCH and never had a failure.....Their magneto today has a even stronger rare earth magnets.....Just punch in Joe Hunt Magneto on your search and it'll come up on the web....You'll note that they don't show the Magneto in there listings on the web site page....All you have to do is contact them...they have em'. Hrdly

31st December 2004, 03:17

First off, great handle! I use that one myself when referring to the ol' HD brand! Hey, thanks for the excellent info, that was exactly what I was lookin' for. I will just set the Fairbanks Morse asside until the '52 K is ready to go and look into the Joe Hunt Mags. I'm familiar with JH as I had one on an old pre-unit Triumph many years ago. Great mags! I wasn't aware that they/he was still making them. I found their site on the web and will be ordering one when the funds allow! Again, thanks for the info!


31st December 2004, 03:27
T-Bone...if the Fairbanks Magneto is original to the K-Model.....I would keep it original and use it with the K-Model. The original mags go for good money at the Antique Motorcycle Club meets.....not to mention on E'bay also. Hrdly

31st December 2004, 03:44
hrdly , I'm glad your here , their starting to ask me questions that I don't have answers for

you'll be a big help here for me

31st December 2004, 05:06
Hey flathead45....I know a little bit.......but I think you probably know more!!

20th February 2011, 01:17
I have a 1973 xlh kick only.
We machined the tach hole in the cam cover & im running a Joe Hunt magneto with Sifton Minus Minus cams.
They have the drive gear.
Also i did the same on my xlch i had in the past it can be done i love kick only magneto ignition ironheads....

20th February 2011, 01:17
Will post pictures soon