This engine looks like a real beast!!!!but then again it is OS oh yeah!!!

That thing is a beast for the size! I bought one new myself! Love it 😊

I love my 55ax it's fixing to go on my new tiger 3

I have one of these engines. Really smooth and lots of power.

Wow Dave, you're wearing a sweatshirt! Jeeze it looks like it's gonna be a great runner. So steady on the rpm. Also congrats on breaking the 1000 subscriber milestone.

such a beautiful series

Hi David just checking out your os 55 ,i have two os 46s that that run good,im looking to buy this os55 in the future.i saw the video with the guy had the head off his and claimed it was making a noise lol, i think these os engines are better than that as your 55 sounds good and they run for many years. Thanks David

David, based on your experience, what do you say about a "back plate" engine mount for the OS55 ? will the casting & bolts take the stress ?

I have that engine and i have a 55ax need to break in and i was wondering if i can use my master airscrew s-2 12x5 for break in.Also how much throttle.

they say to run a couple tanks through. what size tank?

Hi dear sir pleas tell.. Fuel castor oil?? I am flies wit asp 52 ENGINE apc 11,6..with my arf kaos 40... Very powerful!!! Fuel using 18 percent klotz..

OS 46AX or 55AX for my Balsa USA NorthStar?

Hello Mr David.I have an OS 55AX-II engine that burnt only 7 liters fuel only.From beginning of break in to now I use Merlin %5 nitro and %18(castor+synthetic oil) fuel.Also I use APC 12x6 and OS No:8 glow plug with supported fuel tank with foam material.Nowadays I have very big trouble with this engine that quits on the air.HSN and LSN adjusted very well(not lean, at rich side).Each flight after take off 2 minutes engine stops(every flight same time stops).I checked LSN and HSN adjustments again and again.I replaced glow plug and brand new fuel(merlin %5 nitro) but I face same problem.Also, I checked fuel tank,fuel lines and tightness of engine screws as well.I disassembled engine and observed that engine in very good condition including compression.Since I purchased this engine I use same equipments.On the ground when I touch to the head of engine, I feel too hot even I can't touch it continously.I don't have an opportunity that measure temperature since don't havea thermometer.Throotle responses-transitions are good, HSN and LSN are slightly rich side.Fuel tank doesn't have air leake.What can be reason that I face this problem? Any suggestion? Thanks in advance.

What is Ideal Fuel for this Engine?

How low can you go on rpm?

Is it really good to run it at such high rpm on its very first run? I was always told it was better to do a first tank of fuel at 1/4 power, then a second tank between mid and full power.

After many years in the R/C airplane hobby, I just recently bought an engine run-in bench. I was never really any good at being able to properly "tune" an engine and I'm hoping to change that. I believe your videos will help immensely. Is there a follow up to this video where you tune it for best performance, to include the Low End needle for Idle and transition?

Oil 18% or 20% sintetic or blend sintetic- castor? Sorry for my questions

I was wondering i have the same engine on my tiger 3 with a 12×8 prop it's running about 10,000 rpm is about right?

David, Do you sell any of those engines ?? ie OS 61