OS Engines O.S. Max 55Hz Hyper

The max 50SX-H Hyper has established an enviable reputation for power, reliability and ease of use. The Max 55HZ Hyper moves that to a whole new level!

Designed primarily with the demands of the 3D pilot in mind, the 55HZ Hyper delivers 61 size performance in a 46 size crankcase. That power comes from the extensive experience that OS has gained over many years and working extensively with the worlds top pilots to refine all aspects of the engine without compromise in any area.

By using the same mounting layout, you can drop a 55HZ into any model that previously suited the 50SX-H without modification. Just the area around the new carburettor is a little bigger and may require adjustmenst to the cooling shroud.

This entirely new engine shares almost nothing with the 50SX-H and has some new features not seen on an engine of this size before. The rear bearing is now designed to resist corrosion, the new 40L carburettor has three adjustments to cater for idle, mid range and full power. Until now, these features were the domain of 61 class engines or bigger. The throttle arm has four leaves so that push pull control is easy from any direction. The heatsink head is bigger for improved cooling as well.

For the first time, OS is also offering a matching tuned muffler as an option part and has been optimised to extract the maximum performance from the 55HZ Hyper. Part number X-OS72144000.

Specifications
Weight	408g (14.39oz)
Displacement	8.93cc (0.55cu.in)
Bore	23mm (0.91in)
Stroke	21.5mm (0.85in)
Power Output	2.1PS @ 17000RPM
Practical RPM	2000 – 20000