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Completely lost the clutch!


A few months ago I bought a beautiful as good as original Electra from 1971. Not a show bike but a bike that has been ridden. I saw him through Peter Barselaar and the bike was at Thijs Hasselt. There was no throttle cable on it but she walked, and she missed the suitcases and some other little things. Already ruined a beautiful evening three times via Marktplaats, many motorcycles with crazy or no numbers and other misery. Not this engine. I came, saw and took her right away. I wanted the old swingarm and drums front and rear. The only thing that is not old was the paintwork, but the fuel tap, all levers, steering wheel, the voltage regulator, cross-head bolts in the block,  you name it, everything original.

The first night I wanted to take it home I immediately spent 2 hours getting it on. Just the throttle cable became a bit more. Instead of walking nicely as she still did yesterday, a lot of gasping and flames and misery. After some looking, I saw that one of the carburetor studs had been violated by a coarse nut that did not fit nicely on a fine thread stud. The air filter housing was also stuck with nothing that the inlet rubbers don't like. I found an original support above, looked for some rubbers and cut a gasket for the manifold. An air filter is also nice I also had it lying around and after some fiddling finally on my way!  

The engine ran quite well, only the gas did not run very well, the front drum brake did a bit but the rear brake gradually got tighter and tighter while driving. Also all the cars started to wave and honk so there was probably something wrong with the lighting and when I looked back, the rear light was a kind of disco light that went on and off at a rapid pace. The suspension saddle sags all the way to the frame, so the sitting position was not great either. What also stood out was the clutch, man man so heavy and bad disengagement. There was a braided steel cable on it, so I wanted to remove it anyway because that is really not a pan on an old electricity. But the best part was, it made me so very happy. I bought my first Harley on my 19th and yes, that was an Electra without a screen, and right, I felt just like then!  

The next day the rear brake cylinder was overhauled and to my surprise the shoes and the rest of the rear wheel looked fine, from Ted from Harley used parts I had received original spotlights, the indicators at the front, a rack at the rear for the mudguard and original suspension brackets for suitcases. I had already asked around for the white original suitcases, but that is becoming more and more difficult. Until Bart came by and conjured 2 in excellent condition from under a rack above, which had been there for about 10-20 years! To my surprise, the wiring was as good as original and an hour of plugging in some wires and adding a few, everything worked again like it did in 1971. Got a new seatpost spring at Zodiac, put cases on it, a new gas and clutch cable, replaced some fuel lines and all ready for battle!  


What a joy and I really rode and enjoyed just about every day. There was one but. The tricky release and difficult shifting, and the clutch went really heavy.   But there is a solution for that!  






Zodiac supplies the APM (American Prime Manufacturing) clutch. This coupling fits Flatheads, Knuckleheads, Panheads and Shovelheads! What you get is a modern inner clutch hub, a large double bearing that you screw into the original outer housing, and a set of plates with no less than 7 clutch plates instead of the standard 4 with a Shovelhead. Also no more loose springs but a diaphragm spring.  

The advantages at a glance:  

Because the outer housing is now screwed in, it cannot move when you pull in the coupling and so there is  more space when retracting the clutch between the plates and the clutch will be released better and no longer "drag".

Because there are many more plates in the clutch, much less spring pressure is needed to transfer the same force or torque. Simply with more plates, a slacker spring can be fitted. The plates are also sintered and have a much higher friction than the original ones. The plates can be used both wet and dry.  

No more pins in the clutch where all the force is applied and that hammer in and bend, which in turn ensures that the plates move less easily when released, which causes drag, so less release and worse shifting.  

Another huge advantage is the diaphragm spring. Ordinary straight springs get heavier and heavier as you pull in the clutch. So actually there is the most power when you are at the traffic light in its gear ..... A diaphragm spring does this much more friendly and is partly for this reason to be found in all modern motorcycles.  

You can actually use this link for 2 things. If you have a motor with much more power, you can place this clutch without almost having to couple with 2 hands. If you have a standard or slightly boosted engine, you will get away with an even lighter spring due to the multiple plates, which means that the clutch is released even faster and nicer, does not feel too heavy, the engine goes into neutral easily and it shifts much better. . There are three types of diaphragm springs from APM available or you can take 1 from Harley-Davidson.  

Assembly is fairly straight forward. To preserve the fingers, remove the negative pole.  Then remove the primary cover, loosen the tensioner and disassemble the clutch and unscrew the large clutch nut (left-hand thread). The front bolt of the compensator sprocket can then be loosened and the coupling can also be removed with the aid of a puller.


On mine it was quite stuck but eventually with some heat it popped off. It is a conical shaft with a key, which is usually a very strong connection. When you take the original clutch apart, you only use the outer housing of the old clutch. Immediately check whether your starter ring is still neat and the square blocks in the house where the plates push against. If they are very worn, you must replace them. Usually there isn't much wrong with that, as in my case.


You press the new clutch housing with the bearing into the old outer housing and this is secured by a steel ring that is screwed onto the back with 6 bolts. A little fiddling with mounting the coupling on the conical shaft and the key, and the nut on it. After this, the plates can be placed in the clutch as described and it is advisable to soak them briefly in the prescribed oil. Then reassemble everything, align the primary chain if necessary, loosen the clutch cable and adjust the pin of the clutch. Tighten until you feel resistance and if the pin wants to open the coupling, back an 1/8 turn, lock the pin and you are done. Then unscrew the play from the handle with the adjusting bolt on the cable and you're done!  

What a pleasure and really what a difference. Easy in free, not too heavy, smooth shifting, much less clapping out of the box, this modification is really a success and I would recommend it to everyone. I drive daily on the newest and thickest motorcycles where everything may work much better, go smoother and much faster, but a Shoveltje wonderfully quiet at 60-70 mph through the polder that shifts nicely can't compete with that! 

The link can be ordered via my website, it is Zodiac number 761028 and comes complete with everything. Competition Master clutch kit, fits all 1936-early 1984 Big Twin

You can order it here , and of course I can also assemble it for you. 

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