LA-40 aka Clark Kent MMR .......

Lordy bee! I uncrated a new LA-40 (C/L venturi and muffler) and put it on the test stand to begin break in for the Twister. I have never before run one of these engines. WHY DIDN'T SOMEONE TELL ME ABOUT THESE LITTLE JEWELS?

Easy start, quiet, powerful, AND OH SO SMOOTH!

Question: 2-4 break or steady run on the Twister? Thanks!

LAST EDITED ON May-03-06 AT 06:07 PM (CST)
 
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Hi John, they are really good engines, I use them here in Colorado on several planes. I run GMA 10% nitro, 25% 50/50 castor/synthetic fuel and a Zinger pro 11X4 or 11X5 prop. I launch them at about 9600 RPM. No 2/4 but a rock solid steady run. I also run muffler pressure to a uniflow tank on some and muffler pressure to a plastic clunk on some. They always seem to run consistantly well and you can't ask for much more than that, hope this helps, Dave

They're really good engines; a good buy for the money. I run a 40 in my Nobler ARF using the stock NVA and venturi. I, too, launch at about 9600 and use a Zinger pro 11/4. I put a SuperTigre NVA on one of my 46's, but the hole has to be reamed for it to fit. Frankly, with my untrained ear, I can't tell enough difference between the ST and OS NVA's to justify drilling out the hole. I'll use the stock equipment from now on, except for the one I've modified. Just my opinion. Enjoy your LA! Glen

The Zinger Pro 11-4 at about 9600 seems to work very well on a lot of airplanes. That is the same deal I am currently using. At last, a replacement for the Rev-Up props of yore!

Hi John,
Do youself a favor and get Leonard Neumann to ship you a tongue muffler, he has some of the best! Matters not if is run with or without pressure but all of mine are on pressure. The LA40 is a very good running engine.

A real good starting place is 5/22 fuel, 60. of .015 lines, 4 - 4.75 ounce RSM or Brodak tank and that tongue muffler I talked about, Zinger 11/6 or 12/5 depending on your ground clearence, take off RPM around 7600-7900 RPM.

Good Flying
Mike Clark

"Chance Favors The More Prepaired Person"

run them in a wet 2 / constant 4 stroke.....they dont like to 4/2 break much but will hold a steady rpm on a 4 stroke....

run muffler pressuer....clunk tank with sintered brass clunk.......works a treat

11.5 x 4 APC or 11 x 6 wooden props work well with these motors.

How do I get in touch with Leonard Neuman? I need a tongue muffler w/pressure fitting for a Series 21 McCoy .40. Desperately.

I guess Len still doesn't put a link on the Forum to his stuff. Actually just erase everthing past the ".com" or

http://www.clstunt.com/

Most of us are aware of Len's enterprise, but newcomer's to his (this!) forum may not know this.

LAST EDITED ON May-07-06 AT 07:20 PM (CST)
 
Any bolt-on tongue (other body part) muffler that fits an ST51 will strap on a series 21 McCoy.

WOW! Is this a FANTASTIC forum or what!!!

Thanks, guys!

I like mine too.

I cut all the extra metal off the outside of the case and it's a good bit lighter but, ugly as #####. I call it the LA Light.

I cut off the remote needle valve and put flat washers under the bolt heads to make the plastic back plate live a little longer. When I got my aluminum back plate I found it was lighter and I never looked back.

I also put an extra gasket under the head and installed SHCS because I planned to take the head off alot to play with different heads/gaskets.

I think mine would run a little more consistantly if it had a better piston fit but, I don't have alot of run time on it yet so, it might still have some tight spots.

Sounds like you've got a good one.

I think of these engines as "idiot proof". Amazing engine for the price.
They really seem to me to like to run in a wet 2 cycle. One would expect the 5" and 6" pitches on a Twister to be pretty fast on 60 feet of lines. Might try an 11-4 APC or 11.5-4 APC.
Jim