DIY reed-valve kit

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This is a how-to to make a reed-valve onto the case of your E-50 engine. This has as an advantage that you can use any cylinder and still have a reed-valve. You could possibly adapt this method to other engines.


  • Cutter + cuttingdisc
  • Dremel with hard-metal die grinder
  • Drill
  • Figure-saw with iron-saws
  • Sculpting knifes
  • Some hand-warm water
  • A 4-valve reed-valve kit from Malossi (For Puch Polini) Or a Peugeot DR-kit
  • A set of good engine casings
  • 2 components expoxystick (Rather Loctite over Bison)
  • 2 intake gaskets
  • Some thread & nuts to mount the intake


To start we need the engine casings. Hack away at em with the cutter to flatten out the case at the top. You want to cut away any material you don't need. You'll end up with something like this:



After that we're going to decide where we're going to cut the hole for the reed-valve housing. Don't forget to take into account:

  1. that you will need clearance to mount the engine after you're done.
  2. if you want the intake to face forward or backwards.
  3. that the hole needs to be right above the crank.

Now we know where the hole has to be, we can mark it up. Mark it on the inside of the case. Use the dimensions of the reed-valve kit you have (obviously) bought before you started. Don't make it bigger than the kit, because you WILL lose pressure.

Make a Spacer

After that, we'll skip the grinding for now. First make the spacer between the reed-valve housing and the case. This is where the epoxy comes into play.

First we're going to measure how big the spacer has to be. Take the reed-valve housing and measure how big the base of it is. The base is where it bolts to the engine. This is also the size of the spacer.

Then we'll have to figure out how high the spacer has to be. Make sure the reed-valve doesn't touch the crank.

Now we know all this we can apply the epoxy.

  1. Rough up the case surface and clean it so there's no grease on it.
  2. Now get a bowl of hand-warm water, you'll use this to smooth the epoxy.
  3. Slap on your gloves and cut a piece off the epoxy stick and start molding. Just use it as clay, put it on and put it into shape with the sculpting knifes. You smooth it out by wetting your fingers and rubbing over it. Do this till your spacer meats the exact dimensions you measured earlier.
  4. When you're done, gently push your (WET!) reed-valve housing onto the epoxy, so you have an outline of how it is going to be.
  5. Let it dry for about 2 days on room temperature.
  6. After it has cured, you can cut out the shape that has formed when you pushed the housing onto the block. The easiest way to do this is by drilling a hole in the center and using your figure saw to cut out the rest. You can finish it with the Dremel if you want.

Cut the Case

This is also the time to cut out the shape in the case.

Then you'll have something like this:





After this great victory (Of course you succeeded, you're a soldier!) we're going to put in some mounting studs. You can't make threads into the epoxy, so we do it a lil' different. Drill out the holes and mount the studs in some fresh epoxy.

Like this:



Then get nuts. Yes, nuts. To go on the threads. Now you can try the house to see if it fits.



After that you can mount it all. Don't forget to use a gasket.


And as a finishing touch: Cover off the intake on the cylinder with a metal plate. Don't forget to use a gasket!


That's all there is to it. Yes, easy as warm apple pie. Good luck!

Translated by SchijnHeilig

Original by BasPuch from