O.S. 55HZ-R DRS Ringed .55 Helicopter Engine

The best engine for a 550 size, live it!

Installed the OS 55 in my new Heli build. I have only run 2 tanks of Cool power 30% thru. so far at only 1/2 throttle I have only been electric.so far, learning something new at every step of the way that's the great thing about this hobby.
My setup will be for open air and sport flying. with some mild 3D

I chose OS for their reliability and ease of tuning for my Tron and Oxy Nitro helis. I’ve always used OS in my helis.

Well made ! Can wait to ear it scream !

This is by far the best motor over all. Easy to tune and has a lot of power for 3D flights.

Always used OS. This engine is reliable and easy to tune.

I’ve been dealing with Helidirect for quite some time now.
I am not a patient man lol. When I order something I want it now.
Helidirect has always exceeded my expectations with their attention to detail and expeditious delivery.
I’ve never once gotten an email days later saying somethings back ordered or that someone’s dropped the ball. This company is on point and beyond.
Thank you all for your amazing service.

so far so good haven't had time to go and test it yet . but it starts right up and sounds good

Runs great as always with the O.S. motors.

I replaced a 55hz hyper with this engine. I'm finding the breaking in this engine quite joyful. Seems to hold consistent smoke and already makes great power.