Introduction: Restoration of a 1973 DKW 535 Moped

Here's the story of my restoration of a 1973 DKW 535 moped (In Germany called a Mofa and limited to 25km/h)

I got this Mofa by chance and it looked pretty well on the internet, although in reality, it wasn't. Many parts were rusted, the lights and brakes weren't working, shifting to second gear was impossible, the bowden cables were brittle and rusted, the tires were porous and the rear shocks were stuck.

The paint that looked great online, was put on without disassembly, so it was all over the headlight, rear shocks, mudguards and even on the cooling ribs of the engine. Plus, there was no clear coat on the moped and the paint wasn't solvent resistant.

Thus, I decided to restore the whole thing and bring it back to shine.

All in all, this took me about a month after work and the result looks quite fine to me.

Supplies

Tools:

  • Wrenches
  • screwdrivers
  • rubber mallet
  • crimping pliers
  • wire brushes
  • cordless screwdriver + wire brushes
  • bucket, brushes, sponges and rags
  • sanding block
  • sanding sponge
  • spray bottle (soapy water)
  • multimeter
  • microfibre towels

Consumables:

  • Soapy water
  • brake cleaner
  • aceton
  • vinegar
  • sandpaper
  • acetone
  • metallic spray paint
  • filler/primer spray
  • 2k clear coat
  • transmission fluid

Parts/Spares:

  • electric wire
  • fabric tubing
  • bolts, nuts and washers
  • tubes and tires
  • new rear shocks
  • exhaust and manifold
  • 5V lamps (5W and 21W)
  • bowden cables

Step 1: Disassembly and Cleaning

The first step was the disassembly and cleaning process, where I took screwdrivers, wrenches and pliers to the test.

I started by loosening the seat, luggage carrier and the side panels. Afterwards, I removed the rear shocks and the back tire, then the handlebar.

This gave me the possibility to turn the frame upside down without damagin the brake, throttle and shifting levers, I only needed to drain and remove the fuel tank before.

After turning the frame upside down, I could access and remove the engine. Whilst doing this, I found the engine being connected to the lamps and the engine switch by a screw clamp for house wiring.

After having disassembled all parts, I started cleaning the frame and all parts I decided to reuse. Rusted parts were immersed in vinegar to resolve the rust, the engine was cleaned, the blue paint was removed, the engine was opened but didn't show any bad signs of wear and tear, thus I only changed the transmission fluid. The brakes were cleaned and degreased, after which they appeared to be in good shape.

After cleaning and drying all parts, I went ahead and removed as much of the old paint and the rust, as I could, using a number of wire brushes, a cordless drill with wire brush attachments, acetone and lots of sandpaper.

Step 2: Painting

After all the parts were paintless and rust free, I had to wait for the chosen new paint to arrive and after this, I used a carton for wine bottles as my makeshift paint booth.

I once again cleaned the parts with acetone and after it was evaporated, coated the parts with a combination filler/primer spray. Then I sanded the parts down once again and repeated the process. The second time I sprayed down the parts with soapy water and wet sanded the filler from 200 to 1500 grit, then left them to dry.

Next I applied 2 coats of metallic purple 1K spray paint and wet sanded the paint in between the runs. I repeated this with the 2k clear coat and left the parts to dry.

Pro tip: Use gloves, that will keep you from coloring your wedding ring and your wife from threatening divorce.

Step 3: Reassembly

When all parts I wasn't able to or simply didn't want to reuse arrived, I started reassembling the moped reversing all the disassembly stages.

I sprayed down the rims to get the new tires on with ease, inserted new light bulbs and replaced the house wiring clamp plus all the old wires by a car connector and heat/UV resistant electric wires, which I placed in a fabric sleeve. I polished the mudguards, connected the fuel line and replaced most of the old bolts and washers.


Before reconnecting the engine switch and lights, I couldn't wait any longer, put a cup of gas in the tank, started the moped and headed for a test drive. Everything worked fine except for the transmission, so I drove back home, finished the reassembly and realigned the transmission, which is quite easy for these small mopeds.

Step 4: Conclusion

In one month, I brought this tiny moped back to life and prepared it for another 50 years of driving.

First I was a little overwhelmed by all the things that needed to be done, but it proved to be far easier than I first thought it would be.

Although these mopeds are technically and legally limited to 25km/h it seems to reach about 40km/h with me(125kg) on it. I don't know why or how, as all parts are either original or certified to be of the same specifications as the original parts, but I take it as a reward for my work.

Nowadays, the moped shares its garage with two other bikes, this sight was called the bikevolution by a friend of mine.

All in all, I have to say, it gets easier right after the start, you simply push aside the anxiety and your hesitations and you'll succeed.

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