The summer is over so is is time to start with the building up of my nice little Yamaha MF-1 1961. Moped/Motorcycle.

The parts to be zinc plated were back already in April and they looked generally okay as you can see from these pictures.

The dimensions Yamaha used in the early 1960's were different from today, an 8 mm bolt has a 14 mm or even 15 mm head, today that is 12 mm or 13 mm. So I do like to use as many as possible the original parts.

Even the old nuts are thicker than modern ones. Washers is not a problem, they can be replaced with new items.

My local bearing and oil seal supplier could deliver nearly all the bearings and oil seals in the proper sizes, Yamaha had none…!

Lagers in zakje

The well-known Dutch wheel builder haan.wheels.com supplied the hand-made stainless-steel spokes.

The very rusty 20” wheels (old size) were of no use anymore and I found good quality Japanese Takasago 16” rims which could be laced properly to the rims. The German tyre maker Continental has various classic tyres in their range and I ordered their 2 ½ - 16 42 B TT KKS10 items.

The wheels were built as you may have seen on the special page by the end of September and are ready to be fitted to the bike now. The rear brake plate was assembled with the brake shoes, grease nipple and other small parts, normal Yamaha construction.

The front brake plate has a strange outside speedometer drive with a plate with 2 tags who lock into the hub. This is sealed by an oilseal which has an extra "skirt" to that side. Fortunately the old oil seal was still okay and could be used.

It is not much yet, but the finished wheels look good!

The coloured parts came back during the first week of October and look great in quality. The painter found the exact colour of grey, which is a Mercedes-Benz truck colour # 7709, or for me MOTIP 46807. Yamaha really had a funny taste for colours because it is similar to Army Trucks!

The welded-in fuel tank was still dirty as far I could detect so I decided to give it a coat of “tank-cure” material. I packed the frame properly in plastic and taped it off everywhere. Next the fuel tank was rinsed with tank cure rust remover for 48 hours. Problem with this bike is that you have to turn the whole frame around several times to let the fluid do its work. With a normal fuel tank it is much, much simpler! After cleaning the rubbish out with clean water I dried the tank for another 48 hours before pouring the 2-component sealer into the tank. Luckily everything went alright and the fuel tank has a nice thick coating now on the inside. I wrapped the frame again in plastic in order to avoid scratches during the assembly, which will take quite some time.

The first step now was to press-in the steering-head bearing cups. Fortunately they were not pitted, because they have a very strange shape and are very difficult to make.

The wiring harness came next. I had checked it already, but all the connections were okay. A few small repairs with tape and 10 second glue, finally a slight silicone spray coating did wonders. The small metal tags in the frame all got a small piece of insulation tubing to avoid shortage and the wiring harness could be pulled through the frame.

206 wiring and 207 wiring harness

Next came the rear swing arm together with the rubber suspension unit. First the upper dish was fitted to the upper bracket with a bolt, nut and clevis pin, then bolted to the frame.

The swing arm was slid into place together with the “Eligo” rear suspension rubber (an Eligo unit is a coil spring inbedded in rubber). While holding the parts together the swing arm axle had to be inserted. This "Sumitomo" rubber is 88 mm high and compresses 10 mm under 120 kg weight. When you "Google" for more information you wil find out that these units are used on train suspension.

Now complete, the rear swing arm must be compressed as far as possible to move the bottoming rubber in and fit that with a bolt and washer.

As the Mitsubishi regulator was already touched-up, it could now be installed together with the rectifier, which fits just behind it. It sounds easy, but took me nearly a day and a lot of coffee!

The ignition coil was okay and with a new high tension cord it is temporarily fitted as I do not know exactly how far the engine protrudes into the frame once it is fitted.

The chrome parts for the headlight show that the bike is nearly 50 years old. The plater could not go any further with buffing as the material is too thin. But it looks okay. I made 2 seals for the lens from tyre tape (thin and it can be glued easily with 10 seconds glue). Draw the outline/inside line on the rubber and cut out first the inside with the smallest scissors you can find, then the outside.

It fitted very well and the rim/seal/lens/seal/reflector could be clipped together without too many problems. I used the original clips as they had such a different shape and simply oiled them after brushing them with a copper wire brush.

The lens assembly hinges on 2 very small pins with circlips (I did not bring those to the plater!). The bulbs and sockets are okay (50 years ago Japanese electrical equipment was already light-years ahead of everything we were used to!) and could be easily fitted.

Next came the handlebar, some provisional checking. Firstly I positioned the flashers (found out on the last moment that they are oblong…) and soldered the wires on. The rivet holes were reamed slightly in order to have good earth/mass for the flashers; next they were carefully riveted onto the handlebar.

New handlebar rubbers are unavailable of course, so I use 116-26241-00 and 116-26242-00 items. These have the correct thickness and length but the throttle is the normal type. For the sliding throttle I have, the end had to be cut-off and a hole made for the attaching screw. It did not go 100%, so I will order a few more 116-26242-00 rubbers (r.h.). The electrical wires for the l.h. and r.h. handle assemblies are roughly cut to length.

I will solder the nipples once the handlebar is fitted and the headlamp nacelle is mounted as well.

After that came some story……..! I wanted to have exactly the same rubber bands for the fitting of the battery. All the original parts were there, even the leather pieces to pull the straps together.

The metal pieces were zinc plated and I had a nice Yamaha rubber battery band of the correct width. Do not laugh… I tried 6 different kinds of glue to affix the rubber straps to the metal pieces. It took nearly a week, nothing worked! I tried glue that would glue your mother-in-law to her chair according to people who know, but still to no success. Finally I went  to my specialist shop, looked in to the Loctite catalogue and purchased Loctite #480. And that did the trick. I have now “original” 1961 Yamaha MF1 battery bands that took a week to make, I covered nearly 200 km and spent Euro 60,00 on all kinds of glue…… (forget the diesel fuel for my van) Nice hobby this is!