Maicoletta /

Late in 2000, we were approached by Graham Fisher (the well known Moto Rumi collector and racer of strange scooters), who wanted us to make him a barrel kit. It was for his Maicoletta sidecar outfit, which he was going to use for racing.

Maicolettas are a 1950's German Scooter.

The standard barrel was not suitable for tuning, but Graham had found a barrel from a military model Maico off road motorcycle that looked like it had plenty of scope for tuning.

 

We are lucky that we managed to get some "before" pictures of the barrel, because no-one would believe the end product, a 40bhp reed valve liquid cooled barrel, could possibly have started life on a 50's army bike!

The barrel kit was not cheap, but it was an interesting winter project for Mark at the time. It shows that Mark can turn his engineering skills to any project, not just Lambrettas!

 

th_maico_1.jpg - 12292 Bytes A view of the barrel before we started working on it. There has been a bit of pre-tuning on the barrel transfers so that we could tune the casings.
th_maico_2.jpg - 13506 Bytes You can appreciate the size of the original barrel now. It was a big cube, each side was about a foot long. It was very heavy with all those fins. The barrel was reduced in size on a lathe and then tidied up on the miller. Then a piece of sheet metal was bent and welded on to make it liquid cooled.
Sounds easy, took 3 whole days!
th_maico_3.jpg - 16942 Bytes A shot of the "spare" engine which was used as a jig to set the port timings before the barrel was tuned.
th_maico_4.jpg - 14227 Bytes Side view with the timing disc on, measuring all the port timings for our records.
th_maico_5.jpg - 10640 Bytes Maico cylinders are always piston ported. This cylinder was modified to use a 6 petal reed valve. With the one off carb mount it looks like it is meant to be there.
th_maico_6.jpg - 11824 Bytes Exhaust port with bridge, showing the one off steel exhaust stub
th_maico_7.jpg - 11089 Bytes A view down inside the cylinder, showing the transfers, boost port and the bridged exhaust port. As you can see it is an iron linered sleeve fitted to the alloy cylinder.
th_maico_8.jpg - 13764 Bytes Another view, showing the barrel with the head fitted. This was just before we measured the compression.
th_maico_10.jpg - 9890 Bytes View of the liquid cooled head showing the combustion chamber, water jacket and the o ring sealing grooves.
th_maico_11.jpg - 9752 Bytes It is hard to believe that this 2 piece head started life as 2 big chunks of alloy bar!
th_maico_12.jpg - 10627 Bytes 2 part liquid cooled head. Looks like the ones we make for Vespas and Lambrettas, shows we stick to the long proven design for other jobs.
th_maico_13.jpg - 10305 Bytes View of the inside of the liquid cooled cylinder head