Is your Sachs moped having clutch issues? Not a surprise, Sachs clutches suck! No worries, here's something I did that made it work like new again.....

I'll show you how to do it.

I made it at Techshop. The have a work bay where you can work on your car, motorcycle, moped... whatever! There are 3 of them around the SF Bay Area, so it's pretty convenient. There's others around the country and they have lots of tools and workshops. Wood, Metal, Fabrics, Electronics and more. It's rad.

Check it out here:       


You'll need:

Sandpaper and a file
A flathead screwdriver
A piston stop
A socket wrench with a 17mm socket and a sparkplug socket

Step 1: What's Wrong????

The Sachs clutch is pretty simply, yet it can have various problems. With your clutch apart, look for obvious problems, like broken springs or friction discs. If those are broken, you'll need to replace them.  Sachs clutches have a tendency to "glaze over", so start by sanding the surface of the friction discs, just a little to remove any shine. Those friction discs are sandwiched between your clutch plates. With rough sandpaper, scratch crosshatches into the surface of those clutch plates. We want the clutch to grip as well as possible.

When the clutch is together, it moves up and down the notches in the clutch bell, and after time it creates burrs in there. When those burrs get big enough, they hang up the clutch and it don't work no more.   :(

Use a file on those notches of the clutch bell, if you have big burrs, just to get it smooth again. Then finish it off with some 220 grit sandpaper. Do the same on the clutch plates if it's rough there. You might need to lightly sand those spots in the friction discs as well.

When you think it's good, put the clutch pieces together and squeeze it to see if it moves smoothly. It should.

Step 2: Disassemble. Reassemble.

Ok, let's put you clutch back into your motor. This job take a little bit of patience to do it. I used a screwdriver to help guide some of the pieces into place, and I did it bit by bit. You may like to chuck the whole clutch in there together, I dunno. However you decide to get it in there, be sure that it's going together in the right order. 

Here's a diagram that I used to check my work. You can find other Sachs clutch diagrams online, if your clutch is different.

When I put on the final washer (#13 in the diagram) I had to get in there and press and line things up correctly while someone else turned the 17mm nut on. Just FYI.

Step 3: Righty Tighty, Lefty Loosie...

Once the clutch is back in, put in your piston stop and tighten down the 17mm nut on the end of the crankshaft. Thems are fine threads, so don't go nuts, okay?

Step 4: Put That Thing Back In, Through Those Things....

Put on duh cap, then put that long bolt in through the top of the motor. As it lowers through, slide it through the spacer, then position and slide it through the clutch arm (with the clutch cable still attached to the clutch arm!) and then through the spring.

The spring needs to be positioned so it will be applying springyness to the clutch cover...

Step 5: Alrighty...

Okay, if your clutch cover gasket is wasted, it should be replaced. If it's reusable, put on the clutch cover and start in the screws. You'll need to press the cover down as you start in the screws as the spring SHOULD BE pressing against the cover.

Screw in all 5 screws loosely, then go back and tighten them down snug in a star pattern. By that I mean, start with the bottom-center screw, then the top-left screw, then the bottom-right screw, then the top-right screw, and finally the bottom-left screw. This is supposed to keep things from warping. Everybody I tell this to calls me dumb for doing this, but that's the way I do it.

Might wanna check your oil level.

I think we're done. Now, go ride your moped-super-bike!!!!!!