Although the frame clearly shows that there is space for a gearbox, the Motobecane is reassembled as a MB1. To make it a MB2 model there are some changes required:
The flywheel of the MB1 isn’t fit for the MB2; the gear wheel is on the wrong side of the flywheel and the flywheel of the MB1 is bigger than the one of the MB2;
The protective cap of the MB1 for the magneto gear wheel is smaller than the one for the MB2;
The magneto of the MB1 sits lower on the engine housing and is smaller in size than the one of the MB2;
The brackets of the protective cap of the drive pulley lack on the MB1;
The MB1 has only half the protective cap relative to the MB2;
Motobécane used more than one kind of handlebars; a more bend one was manually made which allows you to sit up straight;
The drive pulley is replaced by a type used by the MB2.
My first test ride:
A moody two stroke
I am the proud owner of a ladies model Motobecane MB1 which my father and I restored together and transferred from a MB1 to a MB2. A MB1 as no gears and/or clutch and due to family circumstances, this isn’t practical for us. A gearbox is a must!
After the restoration the inspection and test drives went without trouble. The first ride and the following rides during the next 2 years, also went without considerable problems. But afterwards…
The problems started during the ride in Hengelo 2009. The clutch slipped and it made the necessary noise.
In itself not so bad , just replacing the small corks. To do so the necessary wine flowed plentifully.
Those new corks seemed to do the trick not entirely; Tensing the belt did the trick. So we thought that the problems were over. And we decided to make another ride in October. The weather was good and the temperature acceptable. Just quickly filling up the tank and than go for the ride. Kick starting was no problem, until I wanted to speed up to ride away. “You do it”, was the answer of my little motorbike. Such things happen so just kick starting again. Starting no problem, but riding away, ooh no! After half an hour we decided to draw out the 1950 DKW IFA and to go for our ride.
The next weekend we analyzed the problem with the ladies Motobecane and we had come to the conclusion that there wasn’t enough compression. First we checked all the usual causes, but in the end we concluded a faulty piston.
There wasn’t a new piston for the taking, so we had to see which entrepreneurs could cast us one. We found one in Wieringerwerf. After contacting the company and sending the old piston, the long wait came.
Ibbenbüren came in sight and I became nervous. All the more because my men’s model Motobecane MB2 also stood still for two years because of magnet problems. Some parts for certain magneto’s are difficult to obtain and that was also here the case. My father had been looking through his old parts to see if anything would fit on the magneto of the men’s model Motobecane MB2. He succeeded, so that I was able to participate in the event of Ibbenüren.
This was, eventually, the only event in 2010 that I concluded without using the assistance of the “bezemwagen”( a tow truck). 3x A flat tyre and magneto problems had made sure that I often saw the interior of the “bezemwagen”. Thank God for the “bezemwagen” during these events!
Because we wanted to replace the piston in the spring, we made a tour around the IJsselmeer. We had our first stop in Friesland, Joure, and after that we went to Wieringerwerf to collect the new piston. From Wieringerwerf we went to Anna Paulowna to meet Jan Petter and to bring him his repaired magneto’s. From Jan’s we went to Hoorn and, finally we went for a peek to Piet Oud in Hem
Coming home we were very curious if the piston would meet our expectations. Reassembling the engine and kicking, kicking, kicking…. No puf, huf or any other sound, just my panting.
Nothing, nada, no sign of life. Using the electric drill . Still Nothing, so taking apart the engine and taking out the piston. After a few test we discovered that the piston leaked. All casting errors. So what to do next?
Jan Petter had shown us what he does and can do during our visit, so I asked advise from him. He milled a new piston, so there was hope again. We built that milled piston in the engine, but it didn’t do the trick either. De engine wanted to go while kicking the starter, but it didn’t make any rpm while throttling the gas. Still magneto problems? To be sure we mounted an other magneto, but this didn’t help. We were sceptical already, because the original magneto sparked very well.
My father sees a lot of volks, because of his wrapping coils activities. In this way he met a person who didn’t live that far from us and even owned a complete Motobecane engine. My father drove straight with him to his house to pick up the engine. It was, indeed, an engine that would fit into the frame of the ladies Motobecane. The ladies Motobecane has a pocket cylinder with a horizontal spark plug en horizontal decompresseur. This is due to the construction of the frame. The little engine which my father bought wasn’t one with a pocket cylinder but it had a horizontal spark plug opening. It fitted perfectly into the frame. It was a revised little engine, so we could exchange it completely.
But who thinks that our problem was solved finally, should think twice. Even this little engine didn’t want to run. But we had options now. Swapping cylinders, fitting pistons, fitting new and used piston rings, etc. We tried a lot of combinations, but nothing worked. The Motobecane did not run!
We were working on our final option, because the seperate cylinder cap of the second engine created new possibilities. I had, namely, a complete set cylinder and a custom made piston on the shelf for the gent’s Motobecane. The gent’s Motobecane has a seperate cylinder capwith a vertical spark plug. Now, the second engine for the ladies Motobecane also uses a seperate cylinder cap. That why we were busy to fit the complete set meant for the gent’s Motobecane on the ladies MB with exchange of the seperate caps. Would this finally solve our problem? And would I finally be able to ride my ladie MB the next motorcycle season?
So you can see that a simple two stroke motorbike can create big problems!
A moody two stroke (part 2)
To answer the last question first; yes, I was able to finish two runs thia season. But, before telling about it, I will first let you know how the repair of the Ladies MB went along.
Swapping the caps wasn’t a success. Despite the complete set of cylinder and the fitting piston of the Gent’s MB, The ladies MB didn’t want to run. We had had it. Let’s see if someone else could solve the problem.
Via e-mail and contact by phone with Jan Petter, it was decided that I should send him the engine and flywheel. So I did. After a few weeks I got the parcel back. So I installed the engine and flywheel quickly to see if she finally wants to run. The first efforts of starting went with some difficulties, but, really, she was running. This lastet only a few minutes. The piston got stuck. Jan Petter sent us an ingenious little rod with klamps after we phoned him, so that we were able to slightly mill off the piston in the lathe. Here after the engine purring like a kitten. One kick and the engine was running. The first testrun was made around the park in the rain, because I couldn’t wait for sunny weather. Ibbenbüren was coming…
On a lovely sunday afternoon we went to Bourtange to test the ladies MB further. The way out was no problem. The engine was purring like a kitten. But after the break she did want to start but not to run through. The engine went dead immediately! My father went home on his Automoto and collected the ladies MB with his van. What a setback!
Fortunately, this time the magneto was the culprit. The contactpoints had to be adjusted what a rather difficult job is by these Novi magneto’s. But I knew the right person for this!
After this little adventure we polished a couple of motorbikes and brought them for a show to Zuidlaren. There the ladies MB was rewarded the second price as we al have been able to read in our VMC-blad.
Ibbenbüren came soon after Zuidlaren. The ladies MB run without any trouble both days. Starting was much easier as before and the engine didn’t sputter once.
My father had brought two motorcycles; the Automoto and his latest acquisition, the Monet Goyon, Automouche, type GZA of 1930. But this is a story in itself. The second run was in Zörbig. The Curbici Veterano was organised there. This run is also a story in itself.
My ladies Motobecane is finally running afer a year and a half of struggling. Afterwards the solution wasn’t that hard. The problem was obvious, but how to regain a new comb piston? Those are not on a shelf. Jan Petter has milled one for me. It is very nice that someone can and will do that, because next to the abilities you also need the knowledge to do such a thing.
Jan, again my whole-harted thanks! Without you my ladies MB would have been still a sad little thing.