Regarding the Monark on picture above, I have not talked with Sten about it myself yet. It is only informations from other persons I have heard and read about it so far. I do not have informations regarding which year this Monark was built either.
When the previous owner took part in a motorcycle exhibition with it, Sten was taking a look on it but could not remember for sure if it was his from the beginning. Sten said that he could see that the system for the rear braking was like he had on one Monark bike. It is quite a long time ago now since these bikes were made in the 1950´s, so it can be difficult to remember also.
A Monark that Sten used in 1959, when he won his first world championship, was sold to Schweiz soon after that win. But it seems like Sten used two Monark bikes in 1959?
I think it is best to say for now that it is not 100 % sure regarding who was the first rider of this Monark I have on picture above. I shall do more research about it.
Earlier, before I had this Monark pictured above, I was talking some with Sten Lundin about the other Monark 500 mx bike I have and showed him pictures of it. After some thinking, Sten said that it was his from the beginning and that he used it for training. I asked him if he had used that Monark in some racing heat for world championship, but no answer about that. I shall take pictures of that Monark also, it is in big need of restorations. It is lightened (in the late 1960´s) in the same way as the Monark 500 mx Sten still have.
On the Monark picture above, it can be seen on the frame construction at the stearing head that it is an early Monark frame as it does not have the upper tube going from stearing head rearwards under the tank. There are two strenghtening plates going rearwards at each side of the stearing head instead.
My Monark on the picture above does not have the original paint left. Original paint is darker blue and looks a bit like metallic colour.
I have not seen any frame number on that frame, it can be there under thick layers of paint.
The engine have a number from Monark and "SL" (for Sten Lundin) engraved.
T-Bond, is it a number on the frame and engine on your LITO from Sten?
I shall also look closer on my front forks that is in exact same special model as on your LITO. I have been told that this forks I have was Sten Lundin´s from the beginning also and that Sten only had these two forks of this special Ceriani model. I wonder if it has longer suspension travel compared to the usual Ceriani from the same period, as the lower legs are longer with the wheel axle moved up a bit at the front.
Italian MV Augusta roadracing machines from about 1955-59 had similar front forks and I know that MV wanted Sten to work for them with development of a motocross machine, but Sten wanted to continue work for Monark.
Sten got good connections at Ceriani factory and he helped them develop forks with good characteristics for motocross.
I write a little more info about Lito, in case some interested people does not know about it:
When the works factory manager Mr Warborn at Monark factory died, the factory decided to stop with mx racing. Warborn had been uncle to the owner of the Lito factory, Bornebusch.
When Monark stopped the racing with these mx bikes, Lito continued with the same construction and built bikes for sale also, with the same type of engine as the Monark above.
Earlier, Lito was building mx engines with BSA Gold Star bottom and the same cylinder-head as on the Monark 500 mx machines. The BSA bottom end is not so strong as the Albin crankcase used on Monark 500 mx engines and later Lito engines, also used on Husqvarna.
The total number of original 500cc Lito mx machines built was between 30-35, they were really expensive.
The cylinder-head on these Lito and Monark 500cc mx machines, and corresponding Husqvarna and Hedlund mx engines, is based on an old Husqvarna design from 1935 that was fitted to a sporty roadster.
That Husqvarna head was designed by the same constructur who designed the Husqvarna TT racing machines in the 1930´s.
In 1942 the head was used again, with some small modifications, in the production of the Swedish "Albin" army engine.
Some years later a small number of roadster bikes were produced in Sweden called Union with the same type of head (introducing excentric axles for the rockers as on these mx engines).
This head has good shape on the channels that give good power and torque
with the suiting cams over a wide rpm range.
LITO also built a few complete mx bikes with BSA-LITO engine in frames that were made by Monark.
I attach a picture below of an old Swedish built motocross machine I had with BSA-LITO engine in a "SOH" frame (the exhaust pipe with special connection to the head is a later modification that is not any good). As can be seen on the picture, the bike is really in need of restoraton.
Lito factory sold a small number of BSA-LITO engines here in Sweden for putting in different frames.
BSA-LITO engine in "SOH" frame below, for restoring .....