chopper man

The engine that I'm wanting to install in my Kaos will not fit between the straps on this engine mount. This looks like the one included in the kit. http://www3.towerhobbies.com/cgi-bin...?&I=LXGAK4&P=7

I would rather bolt the engine to the mount anyway. Am I taking a chance of weakening the mount if I drill additional holes?
Thanks for your help.

Gene

jester_s1

You won't hurt it a bit. I've never liked the strap type mounts anyway. In an environment where the surface is getting doused with oil and high frequency vibration is constant, friction isn't very reliable. If you have bolts running through those holes though, the engine won't go anywhere. Do be sure that the holes won't be right at the edge and tap them for threads. A shot of blue loctite will keep the oil from penetrating the threads and letting the screws vibrate loose.

stevenmax50

My Feedback: (1)

you will want to clamp the mount in tight and use a drill press so the new holes will be straight and round.  and the edge distance between the new and old holes should be at least twice the diameter of the hole.

JohnBuckner

My Feedback: (1)

Any airplane such as a Kaos that has a non removable tub type cowling (If you have the current arf forty size it may be a removable cowl, don,t know) You really need a round mount and not those humongous square adjustables and I definately avoid the clamp type mounts for that airplane.

The mount you linked would work fine, my preferance is for the Dave Brown mounts and use those on almost everything:

http://www3.towerhobbies.com/cgi-bin...?&I=LXB872&P=7


John

chopper man

Thanks for the input. I want to try and avoid buying a different mount because the holes will most likely not line up with the holes already in the firewall. I will have to modify the front of the cowl in order for the engine to fit.

hogflyer

Are you talking about the Tower Kaos? If so, you'll want to use a good bearing .46 like a TT.46 Pro or else it'll be a dog. Which engine are you planning on using?

I literally flew the covering off my Tower Kaos (covering split from the glue/coloring and ripped off, and the several layers of packing tape wouldn't stick any more) flying with a Thunder Tiger .46 Pro, OS .46 AX, and for a short time with a Thunder Tiger .40 Pro to break the engine in. The performance was not all that good with the .40 Pro - just not enough power. It achieved at best 75' vertical with the .40, but an easy couple hundred feet with the worn .46. Keep in mind the Kaos design is a pattern style plane from the 70's and likes to fly fast. Yes it'll land slow due to that fat wing, but it's not much fun flying on the lower end of the speed range.

As far as the clamp mount goes, I put well over 1000 flights on mine before retirement and never had any issue with the engine becoming lose or shifting position. I've flow that style mount on many planes - my own and many students trainers and had the same experience. There's nothing wrong with the clamp style mount - it's well proven over many years.

Hogflyer

chopper man

It is the Tower Kaos. I was planning on using a Magnum .52 4 stroke. I have used the mounting straps before and have not had any trouble. The problem with this set up is that in order for the engine to fit I have to slide it forward and by doing that the engine flange covers the forward hole in the mount rendering the straps useless. That is why I wanted to drill additional holes.

Gene

jester_s1

I can go ahead and tell you that engine isn't going to be powerful enough to do anything more than small loops and any horizontal maneuvers. It won't be able to get the Kaos up to the speed where it really performs well, and it won't pull it vertical well enough to get good scores even in novice (if you plan to compete). I have a Kaos and I have that Magnum engine on a Cub. It's barely enough power to putt around the field in a .40 size Cub. If you want a 4 stroke in it, you'll need at least a .65 from one of the more powerful brands like Saito, and preferably a .70. That said, you're going to have more torque issues from the big prop the 4 strokes turn, and it will make your flying more difficult. You're much better off using the engine that Bridi designed the plane to fly with, which is a hot ball bearing .40-.46. I have a Thunder Tiger .46 Pro in mine, and it is appropriately powered. Not overpowered, but enough to make nice big loops and hammerheads if I want it to and it will pull the plane through a big enough top hat to score well. Quite a few pilots put OS .55 AX's on the Tower Kaos to give it enough speed to knife edge well, but then you're getting into torque issues again.

hogflyer

As Jester said, DO NOT use the magnum .52 4-stroke. I've flown a Tower Kaos with a Mag. .52 4-stroke on it and calling it a dog is an understatement. It struggled in the air and had no vertical performance. You'll want a heavier .70 sized 4-stroke if you go the 4-stroke route, but the plane performs best with a .46 bearing engine which is was designed for. Like I stated in a previous post (and jester also), the Thunder Tiger .46 Pro was a perfect match for the plane (and my engine, though getting down on power due to around 1000 or so flights) still has enough left in it for some decent aerobatics.

Anyway, just my thoughts based on actual experience/use with the Kaos.

Hogflyer

chopper man

Thanks for the input. Being on a tight budget what do you guys think of this magnum?
http://www3.towerhobbies.com/cgi-bin...?&I=LXBUX6&P=7

Thanks for the help.
Gene

Mk23socom

My Feedback: (7)

I used two of those magnums in a couple airplanes in mine and loved them.. they really flew the snot out of my sport planes. If i HAD to go back to glow, this is one engine I would always keep on my benchstock, just in case.. You get a thumbs up from me on this engine.. I had no trouble tuning it the same as I tuned an O.S., I say go for it, you won't be let down.

landeck

My Feedback: (1)

I have one in my Escapade for the last five years and it has preformed great!

Bruce

chopper man

I think I'll go ahead and go with the magnum .46 2stroke. It's amazing how much I have forgotten over the last 3 years of being away from flying. Thanks for your input, it sure helps blow out the webs in the old brain.

Gene

jaka

Hi!
That engine is one of the most powerful .46 engines on the market. Very good engine and reliable too! But get a Dave Brown plastic motor mount for it! The alu mount you showed us is no good!

Just take a round dowel and stick and glue that inside the motor mount holes you now have and then Ca glue (spot glue) the new plastic mount where you want it. Then drill holes with a long drill bit through the motor mount holes into the fire wall and then remove the mount.
Redrill the holes a little bigger and put in four blind nuts. Secure the blind nuts by screwing in 4mm allen head bolts.
Then take the mount and fasten it to the firewall with long 4mm allen head bolts!

JohnBuckner

My Feedback: (1)

Hi Chopper Man

I feel quite relieved that you have decided aginst the four stroke for that airplane and I quite agree with most all who felt that the listed engine would be a dog on that airplane and it certainly would fly but never be able to perform to its best. Every airplane has its mission and no particular engine type fits all.

This airplane is definitely best suited with a good two stroke as was intended, Remember This airplane is a descendant of a long line of Kaos' that were intended for old AMA pattern type aerobatics which was flown at fairly high speeds and is a completely diffierent type of flight from what is normally called 3D Actually those airplanes a by comparison are quite slow.

As to the Magnum .46 While not my favorite engines (for reasons that has nothing to do with just power) can work for you. Yes I have used many of the .25 sized Magnums of the same model as well as several of the .46's in the past. What you will find with the cheapie engines is consistency some may be great and some less so. This factor is perhaps not quite as bad with the magnums as some others.

I also would like to say I completely agree with Jaka in the choice of using a Dave Brown mount in place of the clamp types also what jaka is suggesting is just plugging your existing holes with sticks (after popping the blind nuts out) and dripping CA then cutting off flush. This is a very common method when relocating engine mounts and it works well. I just mentioned it in a different manner to make it more understandable, Hm hope I succeeded

Also Jaka proposed another trick I have not tried but sounds like a wonderful technique that I certainly am going to perhaps give it a try some time. I believe what it entailed was actually just sticking the mount in position and using a bit of CA to hold it for drilling actually using the mount for a drill guide[8D]

Now I have always been in the habit of mounting the engine first to the mount then positioning the engine and mount assembly in position making things pretty simple to position the engine with the mount so what I normally do is use a wonderful little tool called the Great planes Hole locator:

http://www3.towerhobbies.com/cgi-bin...&I=LXK378&P=ML

About eight bucks and to me almost indespensable . With this tool its easy to position the engine mount assembly where you want it and mark the hole then just sit the engine aside and drill the holes. This tool is just as useful in marking the beam holes for the engine mount and makes it a breeze, I would bet the trouble and fear the fellows have in drilling them pesky beam holes is why those clamp mounts are still around.

John

chopper man

Again thanks for the help. If I go with a Dave Brown mount what or ow do I go about mounting the nose gear to the firewall?

Gene

JohnBuckner

My Feedback: (1)

Gene You know what I forgot is that this Kaos uses a nose wheel type engine mount and its likely that you may have to little room for a separate nosewheel block. The DB mounts are not set up to carry a nosewheel.

Actually I think this thread started because the four stroke engine would not fit the clamp mount that apparently comes with the airplane but come to think about it, since you are going with a two stroke now and the engine should fit so it all a moot point anyway. Just go with what the arf came with and there is no real point in changing out mounts and doing all that extra work work.

John

rcjetflyer0718-RCU

My Feedback: (1)

instead of buying the dave brown mount and purchase the hayes mount http://www3.towerhobbies.com/cgi-bin...?&I=LXK797&P=0 you can run the nose gear wire through the mount.



I had a tower kaos with a magnum46 with the included motor mount all i did was blue locktited the screws; you dont need to change the motormount with the 2 stroke engines. I flew the Kaos for 4 years before I gave it to a 9 year old who after learning to fly could fly better than me.

JohnBuckner

My Feedback: (1)

Now there is no reason for changing the mount since the decision to use the type engine the airplane was intended for.

rcjetflyer0718-RCU

My Feedback: (1)

I should of read your post before posting mine

JohnBuckner

My Feedback: (1)

Ah No problem and Its interesting, just had a discussion at the field today about if the Hayes mounts were still out there but there ya go. Heck I got a great idea from Jaka about tack gluing the mount to the firewall then drilling the holes using it as a drill guide. Gotta try that sometime[8D]

chopper man

Thanks guys. I'm going with the magnum .46 and the mount that came with the plane. I appreciate all of your help! One other question. What size prop would you run?

Gene

AlmondRancher

Gene,
Iwould use a 11x6 propeller. For break-in, you will want to use a 10x6 propeller.

- Allan B

tony0707

Go with an APC 11/6 after you break it in
That size prop offers the most torque ( for vertical ) and helps with throttle control on your final ( prop drag slows the aircraft )
RULE larger prop with less pitch , that keeps you in the top end recommended RPM range of the manufacturer

tony0707

Do consider the Evolution 46 or 52 two cycles
The 46 is more powerful than my OS and supertiger 46 engines ( more like 50-55 power )
These engines just never caught on , but have brute power for there size , are true chrome cylinders and built for the long hall
I bought one at a swap for 25 dollars and was amazed at the power , owning many OS engines of all sizes and series
Building and flying more than most for 24 years , so i was surprised
The engines are around alot in the 50 dollar range and originally came on a HORIZON trainner as best I can recall
Is truly a great 46 if it was 150 dollars , and one of the hobbys well kept secrets , as they have never become popular for some unknown reason