Monday, March 14, 2011


O.S. Engines in Japan have released some info of a new 3.5cc inboard marine engine called MAX-21XZ-M. The new engine is a long-stroke motor (the old MAX-21VZ-M is/was a short-stroke) and seems to be based on the geometry of the MAX-21XZ-B buggy car engine.
  • Displacement: 3.49 cc (0.213
  • Bore: 16.27 mm (0.641 in.)
  • Stroke: 16.8 mm (0.661 in.)
  • Output: 2.75 ps / 33.000 RPM
  • Weight: 307.5 g (10.85 oz.)

O.S. MAX-21XM Ver.II

O.S. Engines in Japan have just released some info of their updated outboard engine called MAX-21XM Ver.II. It looks like the water cooling head is gone in favor for a air-cooled one and there is an muffler extension added. The power numbers are unchanged though.

  • Displacement: 3.46 cc (0.211
  • Bore: 16.60 mm (0.654 in.)
  • Stroke: 16.0 mm (0.630 in.)
  • Output: 1.3 ps/25.000 rpm
  • Practical r.p.m. range: 3.000-25.000
  • Weight: 682 g (24.0 oz.)

Friday, March 11, 2011

Propster - Electric Ice "boat"

A friend of mine from Uppsala has made his own full-scale electric Ice "boat" that he will run on the Orsa Speed Week this weekend. This winter he has modified it with front and rear suspension, new "skates" and more power. Its powered by a HUGE brushless outrunner motor and lots of LiPo cells. In practice (the video above) he topped it out at 133 kmh! :)

A forum thread in Swedish about the Propster project.

English Google translation of the above forum thread.

Update: the official time Jonas got on the flying 1000 km was an 130 km/h average with a top speed of 143 kmh!