News:



  • June 15, 2024, 12:19:52 PM

Login with username, password and session length

Author Topic: Super Tiger G-21 40  (Read 2901 times)

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Super Tiger G-21 40
« on: October 06, 2007, 09:47:58 AM »
I just got a RC Super Tiger G-21 that has 40 stamped on the side. It has a baffled piston and twin ball bearings. Will this make a stunt motor and if so what do I need. It came without a muffler but did have one at one time as it has the tabs for one that show signs of use. It has great compression and is really smooth when you spin the prop.
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline RandySmith

  • Administrator
  • Trade Count: (0)
  • Admiral
  • *****
  • Posts: 13747
  • Welcome to the Stunt Hanger.
    • Aero Products
Re: Super Tiger G-21 40
« Reply #1 on: October 06, 2007, 01:52:31 PM »
I just got a RC Super Tiger G-21 that has 40 stamped on the side. It has a baffled piston and twin ball bearings. Will this make a stunt motor and if so what do I need. It came without a muffler but did have one at one time as it has the tabs for one that show signs of use. It has great compression and is really smooth when you spin the prop.


Hi Mike

They are a fair stunt engines some people like them, however they are nowehere near as good as the big brother G-21-46.
The 40 is almost the identical motor to the 46 except it has a small piston (small bore longer stroke in relationship to the 46) Does your motor have a CL NVA and venturie?  I have  mufflers for these and most all ST engines.

many people used these with an 11 x 5 prop in a rich 2 cycle

Regards
Randy

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #2 on: October 06, 2007, 05:07:04 PM »
Thanks Randy It came only with a RC carb but I scored an original venturie on ebay still in the package.
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline rustler

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 719
Re: Super Tiger G-21 40
« Reply #3 on: October 07, 2007, 01:33:38 AM »
G21-40 has significant amount of sub piston induction, and I believe hence suffers more than the 46 with addition of muff. S.T. made the effort to eliminate s.p.i. on the 46, but for some reason never bothered with the 40.
Ian Russell.
[I can remember the schedule o.k., the problem is remembering what was the last manoeuvre I just flew!].

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #4 on: October 08, 2007, 07:05:06 AM »
Ijust looked and your right rustler ican see the piston skirt com up a little in to the exaust. Any cure for that or get a muffler for a 46?
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline rustler

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 719
Re: Super Tiger G-21 40
« Reply #5 on: October 08, 2007, 03:51:13 PM »
Hi Mike. The easiest cure I can think of would be to have a special cylinder made with the bottom edge swept up to cover the gap left by the piston skirt! If you meant fit a 46 muff, it's the same as for the 40, so no improvement. If you meant get a 46 and fit a muff, that was my next suggestion.
Ian Russell.
[I can remember the schedule o.k., the problem is remembering what was the last manoeuvre I just flew!].

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #6 on: October 08, 2007, 03:56:57 PM »
Well I"m going to give it a try in a plane and see what it does. I got it free so anything but being a pig it should be alright for somthing.
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline Jimmy R. Jacobs

  • Trade Count: (0)
  • Lieutenant
  • ***
  • Posts: 68
Re: Super Tiger G-21 40
« Reply #7 on: October 08, 2007, 04:16:16 PM »
   Mike, I use one of Frank Bowman G21-40 engine an it had a nice 4-2 run. Frank never said if he did any thing to it or not. I need an engine an he said use this one tell he made the repairs my G21-46 needed, but it had a good 4-2 stunt run. So I have seen one do it. y1


                                                        Jimmy

Offline rustler

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 719
Re: Super Tiger G-21 40
« Reply #8 on: October 08, 2007, 04:39:22 PM »
Well I"m going to give it a try in a plane and see what it does. I got it free so anything but being a pig it should be alright for somthing.

Go for it Mike. I didn't mean anything I said to imply it's a bad engine. We used them in the early days of rat quite succesfully, and if you fit a muff. it could well prove to be a pleasant useable motor. I'm a great admirer of S.T. engines.
Ian Russell.
[I can remember the schedule o.k., the problem is remembering what was the last manoeuvre I just flew!].

Offline EddyR

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2561
Re: Super Tiger G-21 40
« Reply #9 on: October 08, 2007, 05:55:32 PM »
Use a tube muffler and it will run fine. Some of the 40's will not run well with a stub muffler as it causes back preasure to re-enter the motor. Some of the ST/56's have the same problem.
Ed
Locust NC 40 miles from the Huntersville field

Offline Air Ministry .

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 5022
Re: Super Tiger G-21 40
« Reply #10 on: October 19, 2007, 03:56:03 PM »

 Throw a .46 piston / liner in if its got muffler ears . And the head .

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #11 on: June 09, 2008, 08:37:59 AM »
Well Guys I had an old Sig Banshee with a LA40 in it and it was getting so I could not get a consistent even run. I think the plastic back plate is leaking. So I put the ST G-21 40 in it this week and got to fly it yesterday. I'm using a RSM 11-6 and uniflow tank open forward in the air flow and a old Merco muffler with the baffles reduced. WOW ~^ it's alot better motor than that LA ever was. I'm running it at a fat 2 stroke that smooths out as soon as the nose is turned up. This is the first motor I've ever had that really ran the way it's suppose to. It gives me more confidence to try and learn more stunts. My first flights were trying to get the motor set right but once I found the right needle setting it flew the same flight after flight. Can't wait to get out and fly it more. #^ #^
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline Just One-eye

  • Another Old Fart
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 198
Re: Super Tiger G-21 40
« Reply #12 on: June 09, 2008, 10:47:37 AM »
When the first Van Loo version of SIG's Chipmunk kit was still new, I built one for a G21-40.  Van Loo had used that engine, but I kept trying to run it in a classic breaking run, and it kept "running away".  I pulled the 40, and used a 46 instead, but then the fuel mileage was much worse, so I planned to cut into it to swap tanks (hadn't left the bottom part of the firewall off to allow the tank to slide in and out).  I never modified it, and in fact never completed the entire finish (I test flew it in monotone, single color - metallic blue).

I swapped away the 40 for a backup 46, built a Skylark (always loved those), and the Chip became my hangar queen.  Interestingly, I ran across someone running their G21-40 in a wet two stroke, and getting excellent performance, but one difference was fuel.  I had been using Ritch's Brew 5 % Nitro, 22 % oil, partly castor, mostly synthetic.  Whoever (and blame my age for forgetting any face or name to match) had that other 40 used SIG 5 % all castor fuel -- 25 % oil, I think.  If I ever have another G21-40, I'll be using more oil in the fuel, and less of it will be synthetic. 

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #13 on: June 09, 2008, 11:04:09 AM »
Well my fuel is mostly synthetic 22%, 10% nitro. It runs a great rich two stroke then a hard pulling two stroke. 2 laps at a very fast two at the end of the tank. Too windy here today to try again maybe tomorrow. #^ It was a R/C motor before I got it and I don't know anything about its former life. I put a ST venturi and needle valve and a muffler and thats all.
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline Mike Spiess

  • bikemike
  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 386
  • AMA #4060
Re: Super Tiger G-21 40
« Reply #14 on: June 09, 2008, 11:12:29 AM »
As Bill Little says a blind hog gets lucky sometimes. n~ #^ LL~
You don't stop flying cause your get OLD
You get OLD cause you stopped flying
St Peter MN
Present Master of the Figure 9

Offline WestCoastOldie

  • Trade Count: (0)
  • New Pilot
  • *
  • Posts: 16
Re: Super Tiger G-21 40
« Reply #15 on: June 20, 2008, 10:17:15 PM »
I kinda don't understand why the ST-40 has garnered what appears to be a less than sterling reputation with the Stunt crowd.

I ran a couple of these engines, that greenaway set up for me, for a few years starting back in the 80's. AFAIK, They were stock except for the venturi and a couple or three head shims.

Rugged, reliable, not the least bit fussy, good 2/4 and used either a 10x6, 11x5 or 11x6 prop. I equiped mine with Big Art tube mufflers and they ran fine. I seldom had any reason to change the needle valve setting. Just fuel up and flip. In fact, mine still run just fine, though the rings are by Bowman and they have new bearings. They'll probably out last all of us!

Man-o-man... An ST-40 will sure wake up a 35 sized ship and you can forget about burning up  piston/liner sets...

If anyone wants one, I have one for sale in the classifieds...

Hawk
Ken Whitehawk

Offline Ray

  • Trade Count: (0)
  • Lieutenant
  • ***
  • Posts: 99
Re: Super Tiger G-21 40
« Reply #16 on: June 21, 2008, 12:33:36 AM »
Personally, I'm not enough of an iron engine expert to recall, although the Tigre 40 was also a Rat Racing favorite, in both front and rear intake versions.  I believe that some 40s shared the Perry Porting and flat top pistons from the G21-35s, while others had the same baffle piston style as the 46.  The reason I have for adding a comment is because I listened to a discussion with George Aldrich and two others about the ST 40 as a stunt engine, and he wasn't too thrilled with them, the way I recall, but one particular alteration that was discussed was really dismissed strongly. 

Apparently, some people were grinding as much as 1/16" from the top of the Tigre piston's baffle, for some reason (maybe someone here, such as Randy, may recall what that was supposed to be good for).  In George's opinion, that was worse than merely useless, it created negative results. 



Advertise Here
Tags:
 


Advertise Here