The R204 is fitted with a buddy seat. It is fitted to hinges on the rear body and underneath is the fuel tank opening. It has a foam filler. Prior to restoration it looked like this:

The seat cover is beyond repair as you can see:

A bigger problem is the seat itself. The metal has corroded badly and is paper thin in a few places:

The ugly truth shows after blasting:

It will need metal replacement which is beyond my skill set. I sent it off to the metal shop and they did an excellent job saving it. Just bring a thick wallet when you go pick it up:

It should now last another 50 years. After powder coating:

There is a lovely gentleman in Germany, Ralf Büttner (mopedbezuege@aol.com), who provides new seat covers. Rather than try and do it myself I sent it to Ralf who repaired foam and cover for 107 EUR including shipping. He did a great job. Tips when you want to do the same:

• Make sure the hinges are installed, as you will have to take part of the cover off to fit them later
• Provide screws for fitting. I used M3 sunk washers and stainless screws. It will depend on what screws were used previously and whether you were able to remove them or drill them out, but it will save Ralf the effort and it will look great.
• There is very little clearance between the screws that hold the seat cover in place and the rear body. I used M4 sunk washers to start with, but one just scraped the paint work. After replacing it with M3 it was just ok, so take care not to damage the paint work.
• The lock button should be installed when the cover is put on, but make sure it’s in loose so Ralf can remove it easily for fitting.
• Take very good care of the rubber stops under the seat, as I haven’t found any replacements online.

The final result will look like this:

A slightly darker shade of red would be nicer, but I’m assured this is the original colour used. I’m sure it will darken with time.