jctpro

My Feedback: (1)

What has changed from last years Magnum 120AR Four stroke and the Magnum 120RFS that is sold today? Is this the same engine or were improvements made?

w8ye

My Feedback: (16)

They don't one a whole lot different. The new one has a bigger nameplate. Bigger webbing around the front end. The new ones also have positive crankcase ventilation just like the OS Surpass III. They also have 120 Four Stroke written on top of the valve cover.

Jim

jctpro

My Feedback: (1)

So they both run the same? I am trying to decide if is worth more money to get the 120RFS over the 120AR. Thanks for the help!

w8ye

My Feedback: (16)

Go to justengines.unseen.org and look at the ASP 120. it is the same engine. ASP makes the Magnum. I bought one there for $184 back in Feb. The exchange rate was a little better then. But you also have to add in $13 airmail. It will be the late model engine.

Jim

Volfy

My Feedback: (23)

The Magnum 1.20 AR is a 2-stroke engine. I believe the AR stands for Aircraft Ringed (engine). The 1.20 RFS stands for Ringed Four Stroke, I think.

The current 1.20AR 2 stroke is what Magnum calls "2nd Edition", which is a redesign that just came out this year. The latest 1.20 RFS 4stroke has been out for a couple of years already.

w8ye

My Feedback: (16)

Thanks Volfy, I had a brain fade and didn't pick up on Magnum's letter game. They seem to be seling old and new two cycles now too with the XLS series of two cycles etc. It gets confusing after a while. Next time I should dig out the Hobby people catalog and check my ABC's?

Jim

Volfy

My Feedback: (23)

No problem, Jim. These engine manufacturers all seem to like playing alphabet soup. Magnum's "XL" sounds just like "excel", which I'm sure was what they were going for. Not sure with what "XLS" rhymes, though.

I could see how jectpro could've gotten mixed up. The HobbyPeople website cross listed some 2stroke and 4stroke engines in their rescpective directories. I believe they just recently corrected many of the misplaced entries.

Hey, I know you must've mentioned before, but what fuel and plug are you using on your 120RFS. Mine (ASP version) is taking a long time to break in. After about four 24Oz. tankfuls of 5% Nitro 10/10 oil, it still won't run run good without the glow driver on it. I'm beginning to think it's the plug. I've used Fox Miracle Plug and ASP's own 'F' clone plug with good success with the smaller Magnum/ASP 4strokes, but looks like the 120 might prefer the OS 'F'.

I have another brand new ASP 120RFS in the box, but I want to make sure I run in the first one good and complete before I fired up the second one.

w8ye

My Feedback: (16)

Mine is also the ASP version from just engines. I noticed it would not run good on the ASP plug (you had to keep the heat on) so I traded plugs with a Magnum 61FS that was setting there that had a OS'F' in it. Anyway, the 120FS runs pretty good without glow heat. I'm running Omega 10% and have a Windsor 15-8 prop on it. I also ran a Windsor 16-6 on it some. They both seem like plenty of prop. After changing the plug the engine seemed great.

I went and ran the Magnum 61 FS the next day with the ASP plug in it and it ran fine too. Now this is an engine that would not run on the Magnum plug and I had to change to the OS 'F' now it runs just fine on the ASP plug?? Different day?? I also have an ASP 61FS. It is identical to the Magnum except for the name. They both run about 9700 with a 12-6 on them.

I still think I'll wind up using a OS 'F' to fly in either.


Jim