Greetings all .

Anyone with any experience of the Aviastar C/L range yet ?

If John Brodak's offering them they must be stunt friendly in my opinion.

Any contributions much appreciated ,

Robin [ ex-pat Brit in the Charente ful of ex-pat Brits ]

Hi Bill and thanks for that.

I wonder why ? Too heavy would be my [ uninformed ] guess ?

Thanks , Robin.

Hi, Robin,
   That virtually no one is actively competing with these engines speaks volumes to me...

It seems that when the Chinese team abandoned them, and went to the Saito's,that kind of put "paid" to them.

Hi Robin,

sorry, I forgot to mention that the engine is the 61.

Martin

On the topic of the Aviastar Engines: What are the differences between the RC version vs the CL version?
                                                   There is a drastic price differential in the 2 versions no matter the displacement.

For what it's worth, here is a commentary on the .53.

AVIASTAR RS-53 C/L
By: Thomas J. Weedman
While I was at the Huntersville contest in October of 2008, Bob Zambelli asked me if I would be interested in testing the Aviastar 53 engine. Of course, I jumped at this wonderful opportunity, looking forward to being the first to experience the flying power of the new Aviastar engine. As soon as I got home, I picked out a profile airplane titled "Rampage" that was built in 1993 by Jim Mitchell of Orlando, Florida. I had purchased the "Rampage" several years back. Jim won several contests in the 90's flying this airplane and it was outfitted with a Super Tiger V-60 by Randy Smith. It has a 57 inch wingspan with 741 sq. inches of wing area and weighs 67 ounces.
The Rampage is an excellent flying aircraft and has never let me down. In my opinion it is one of the better airplanes in my fleet which consists of a collection of approximately 40 or so airplanes.
First, I had to retro-fit the aluminum motor pads because it does not have the same bolt pattern as the Super Tiger V-60. I did this by drilling and tapping the aluminum motor pads with a 440 bolt to the Aviastar bolt pattern. Then I had to remove the motor and bench run it to break it in before testing it on the plane.
This motor was fitted with an Aero Products P.A.65 needle valve assembly and a Sig Idle Bar Glow Plug. The fuel was Brodak 10% nitro with 11.5% castor oil and 11.5% synthetic oil.
The break- in props were an 11-4 Zinger and a 12-4 Zinger. The motor was run at three minute intervals for 36 runs from a cold start every time. The RPM with the 11-4 Zinger prop was at 9800 rpms, and with the 12-4 Zinger prop it was at 8000 RPMs.
The first propeller I used was a 12-5 Rev Up propeller. This turned out not to be enough propellers to pull the airplane with an Aero Products Super Tiger 60 tongue muffler, which uses the same muffler bolt pattern as the Aviastar. The propeller of choice is a 13 - 5.5 Bolly carbon fiber propeller (Aero Products). After several flights I added two head shims, and this provided a good 4 - 2 break run. This relaxed the motor to a good stunt run and it ran consistently.
Then I decided to try an Adamisin Expansion muffler. After several runs, I discovered I would need to add one more head shim, for a total of three head shims to get the 4 - 2 break I was looking for. This motor has a lot of power and can fly most .60 size aircraft easily. Fuel consumption was 5.5 to 6 ounces of fuel to fly the complete pattern.
The only thing I would suggest changing on the motor is the bolt pattern because no other engine that I could find (at least in my collection), has the same pattern. The closest thing I could find is the Super Tiger 51, which was the closest to the Aviastar pattern. If the bolt pattern on the motor was changed to something more practical, like the Super Tiger 51 pattern, more people could drop one of these fabulous, powerful motors in their airplane and have more standard power than they have with the Super Tiger 51. This motor will give their airplanes more stamina and punch for the long haul.
The Aviastar performed very well on the Rampage and it actually flew better with the Aviastar than it did with the Super Tiger V-60, which made me very happy. Even though I had to make a few modifications to make the motor fit the plane, it was worth all the effort in the long run.

Dave Gierke had this line a few years back. Ran into him at the Toledo show...must have been ten years back anyhow. He couldnt tell me much about them either. I think the opportunity presented itself for him to acquire them or distribute but he had no real experience with them despite his illustrious past in CLPA. They sure looked well made though and I was considering one at the time. I would love to hear that they work great!

For what its worth, my buddy flew his 64oz. T-Rex/Avistar 61 this past week-end at the Baton Rouge contest. The motor performed very good during practise and cpower of the old ST. I have seen Heavier ST.60 powered aircraft than the T-Rex pulled with  more authority than the Avistar. In fact, there was an ST60 powered large Forerunner that was heavier and larger than the T-Rex at our contest. I've seen Stalker 61's and Avistar 61 compete and in my opinion they fall short when compared to the ST.ompetition. Just as it did a month and a haif ago the motor ran with a soft 4-2 break. That being said, if it was compared to an ST.60 I don't think it has the the torque or  I believe the Avistar 61 is as good as the Stalker 61 maybe a little better, but that is based only on the (2) I have seen in competition, which is not a reliable assessment.   

One of the 2 Stalkers Joe is talking about is mine,  and I'll be the first to admit my set up was not the optimum.  I am working on changes based on recommendations I got from a couple of experts at the BR contest.  There is definitely room for improvement.  Also keep in mind that the Stalker/Chevelle is 4 oz heavier than John's T-Rex.  (I'm working on that too, so watch out for next year)

There have not been many posts on the Aviastar engines. If so I have missed them on the search application. I just got one .61 C/L from Brodack's to put on an Stiletto 660 from B.R.F.R. I always take new engines completely apart to the bare crankcase with the crank. I never did it until a few years back (Fox combat special ~25years ago) was destroyed in one flight due to slivers on the piston/liner. It looked as if someone gouged it with a dremel tool. The one sliver welded to the piston and locked it. As far as clean engines, the new O.S.'s that I have taken apart( Gemini, Fx's, Max H, FP's, etc.) have been spotless.

 The Aviastar engine has a definite bite to the point that I thought it was hitting the head. The .1mm shim comes separate from the engine. The cylinder liner is very VERY thin which leads me to a fear of running the engine lean by accident. The chrome or nickel might strip. The head shim is huge (thick) and has a squish band that has a slight taper to the center approx. 1/16. It reminded me of the Foxes .36 Combat Specials. The main combustion chamber is ~ 3/8 in. in diameter (eye balling) The edges of the squish were extremely sharp. This can produce unpredictable detonation timing so I rounded the edges of the chamber for a better surface exposure and predictability. No "o" ring for the venturi was provided an a ring was installed. Needle valve was very hard to insert after that but manage to press the venturi down on the intake manifold to install. Very impressed with the valve. Mica gaskets were on the needle to seal the gap which was in very tight tolerance, hence the difficulty on insertion with "O" ring on venturi. Slivers were found on the venturi and crank area. A red mark was present on the Aviastar logo on the crankcase. I do not know if it is true that BDK reworks the Aviastars; hence the red dot. It might explain the slivers of aluminum.
 I never bench run engines as that is not realistic operation. I fly the engines on a test plane set very rich. Engines do not stop and start in flight. The loads on a bench test can not be duplicated as if it were in flight looping down sides, 8's, etc. Perhaps that was necessary in the classic days with steel cylinder/chromed or nickel, etc. With the metalurgy advances in the last 20 years, I find it hardly justifiable.

Will report back when in flight...

Well, I flew the engine with the Stiletto 660. 14 oz. later (2 tankfulls), I decided to send the engine back to Brodack's for their inspection. Upon taking the head off again, I can not see any possible interference with the piston. Head on and not tight, there is no "bump". Head tight, "bump".  Now the rod sounds like a lawn mower's when the crank is rotated clockwise and reversed quickly in short strokes. The only thing I can guess at is that the liner gets distorted or hits something at the bottom end. I was in luck when checking the Evolution 60 that I won here, it is a drop in to the Aviastar 60!  Just about an 1/8 of an inch of shorter nose. Will fly the Evo next time I have a chance and report on the engine. The Aviastar with a Zinger 13-5 and a rich 4 would go into a nice 2 when it was pointed up (wing-over). But, I believe that the prop might be a bit too much as I felt the engine load and vibrate the lines for a few seconds and then it would go away.

Will report back....

Rafeal: You really need to update your break in procedures. Running an ABC or ABN around in a rich 4 stroke was great back in the iron piston days, it will ruin a modern engine. The really need to be bench run in a FAST 4 stroke with occassional trips into the 2 stroke realm. Most due it 2 minutes at a time then let the engine cool down. This heat treats the internal parts and will result in a a smoother, longer lasting engine. 

As far as taking it completely apart before running, I vote NO. I'll remove the back plate and blow out the engine with compressed air but completely apart...Uh Uh. To me that would negate any warranty that may have been offered by the manufacturer or importer. Your critique of the Aviastar and its issues is somewhat suspect as I don't know if the problems are factory supplied or were caused by the dissassembly.

  Second that one, WHY would you take a brand new engine apart in the year 2011?  Yes, back in the Fox days, it might have made sense, but not any more.

   Brett

Brett,
First of all, I've found metal slivers, cloth, shipping foam, gasket, missing head shim, wrong glow plug, missing "o" rings, etc. on YS, OS Ultimate Surpass 70, K&B 40-5.8-6.5-S40, ST. 35's, Foxes, Moki 2.10-1.8, 3W 120 twin to name a few NEW out of the box engines. Unless we can guarantee that a new engine will be spotless inside, it is a good practice to do the inspection.

   OK, if you feel you must,  but then you can't too surprised when it doesn't run properly.

      Brett

This has evolved into any interesting sideline - that of Q.C. of model engines.

I have had it put to me by an engine designer and builder that more damage is done by initial disassembly than just running it as it comes from the factory but he is an absolute fanatic with cleanliness, and more importantly the engines in question really do need specialist knowledge to reassemble - things like torque settings, shimming etc.

But I highly doubt that a generic design like an Aviastar will ever need any type of specialist knowledge for a repair or rebuild, so there should not be any run 'surprise' in store for any competent builder and flier.

I had a brand new OS LA 46 arrive this morning (despite my criticism of them, they are a good stunt engine!). Idley turned it over and looked in the exhaust port. There were foreign bodies visible on top of the piston. I hooked them out and found they were aluminium swarf.
  I think a look through the exhaust port and removal of the backplate is good practice. I was shocked at what I found. OS QC may be good, but there is always a chance of this happening.

Andrew