ST G.61 ring or ABC?

Why would you want to do that? Most of them I have seen run do better with the ringed version.

If higher RPM is what you are after then that would be the way to. You should first confirm that the parts you need are available and would work in your motor.

Yours is the first negative comment I've heard regarding Super Tigre ring vs ABC. I own other brand ABC engines [OS and K & B] and they perform well and are reliable.

You say the ringed Super Tigre G.61 runs better than the ABC version, but I don't know what that means. Could you please be more specific? Do they overheat? Hard to start? Won't hold a needle setting? ???

Anyway, I have several reasons for considering the change from ring to ABC setup:

1) the ring and sleeve parts are currently unavailable and there's no projected delivery date. 2) the ABC sleeve and piston set will be available in August.

3) according to Super Tigre's specifications, the ABC version of the G.61 produces .1 HP more than the ringed version. Not a big difference, but at least the change is in the correct direction.

4) my sleeve and ring are worn and need replacing. The soon-to-be-available ABC setup seems to be a better (only) choice than waiting for who knows how long for the ring setup.

DS

For those interested, I just received a response from Tower regarding my question and the answer is yes, the ABC sleeve/piston assembly will fit in the standard G.61 ring engine with no other modifications.

DS

It is VERY RARE to have to replace the sleeve when replacing a ring. Model engines do not wear enough of the sleeve that cannot be fixed with 600 grit wet-dry paper rotated in the bore while moving it back and forth in the bore to put a light crosshatch in.

Then put the new ring in, and run a new break-in on the engine.

How much is a ring compared to a new ABC piston-sleeve set????

David

Well, then I got the rare one. The sleeve has a VERY visible ring-ridge near the top. Of the many RC engines I've owned, this is the first time I've ever had to replace a sleeve due to wear. I don't know if I got a bad sleeve or it was bad fuel (Power Master, fresh from the store) that caused the unusual wear. I had been running Cool Power, but when I switched to Power Master 5% I noticed dark oil on the tail feathers. I'm not saying Power Master is bad fuel, but obviously my ST G.61 did not like that type of fuel. When I switched back to Cool Power, the dark oil disappeared after 2 flights. But, the damage was already done (low compression).

DS

Since the HP figures of all manufactures are pure fiction the differance between ABC and ringed is likely also fiction. The ring costs less. Seems like a no brainer to me. I have only seen a worn out sleeve once. Have a 2 G-61 ringed blueheads with original sleeves.

I'm sure it's not your intent, but you guys (Sport Pilot and David AMA40795) are starting to sound a little conden- scending. Of course it's a no brainer to only replace the much cheaper ring only. On the same note, I don't mean to sound condenscending, but I wish you guys would really READ my posts if you plan to make a response. As I just mentioned earlier, my G.61 has a very worn sleeve, exhibited by the ring-ridge. Yes, I do agree (again), this is rare! I also have many other engines including a 25+ year old Bluehead G.60 and a 30+ year old ST.56. Both of these engines have rings and chromed cylinders and to this day they both have excellent compression and no visible signs of wear. Both engines have hundreds of flights on them. The only reason I don't use them anymore is simply that they don't produce as much power as modern engines of comparable displacement.

So, with my G.61 I'm faced with replacing the sleeve and as I mentioned earlier, the ring/sleeve setup is NOT available and there's no projected availability date. On the otherhand, the ABC sleeve/piston setup will be available next month. Also, when you add up the cost of a ring and appropriate sleeve vs the ABC sleeve/piston set, there isn't much cost difference. So what's better; getting the engine back together next month and spending a small amount more for the ABC setup, or waiting indefinitely for the ring and sleeve setup? What would you do???

DS

David...

I wouldn't hold my breath waiting for the ABC piston/liner assy to come from "The New SuperTigre"... Most of the SuperTigre products that should be available today are still vaporware...

Remember what happened when Hobbico took over the OPS line when Bob Murphy of Shamrock Imports passed away?? OPS was immediately priced out of the market, and today you won't find them on a Hobbico site... OPS aero engines are just about dead in the US, and at one time were king o' the mauntain in Pattern...

I, and many colleagues more knowledgable in this hobby than I, believe that was done to protect Hobbico's OS Engines market share in the USA, and I would not be surprised to see it happen again, with the ST line....

It's just business....

Bill

---- Original Message ----- From: "DS" Newsgroups: rec.models.rc.air Sent: Wednesday, July 02, 2003 11:41 AM Subject: Re: ST G.61 ring or ABC?

I take it Hobbico is the exclusive importer of Super Tigre products?

DS

Hobbico/Great Planes bought the Super Tiger CO. and moved all the manufacturing equipment to China. So I guess they are the exclusive importer of Super Tiger. All new Super Tigers will now be marked Made in China.

Why not just replace the ring and sleeve since that would be cheaper?

*Runs like hell!*

You missed MY point and proved your OWN point. Apparently you didn't read the "*Runs like hell!*".

I was kidding!!! I read ALL of your post; the ring and sleeve combo is unavailable; the ABC piston and sleeve combo is; the ring did excessive wear to the sleeve as evidenced by the marks on the sleeve; the ABC engines you have are 25+ years old with little or no wear and excellent compression. This was typed from memory.

Damn, dude! I was pulling yer leg! I surely wasn't expecting it to come off in my hand.

Your post was far from clear, Fubar. "*Runs like hell"* can mean anything, good or bad. Sometimes it's appropriate to use smiley faces, etc.

DS

Guess you never did RPG's online.

*grins* Sorry you misunderstood my post. *shrugs* Just got back from working on my plane hauler and Im starved. Later! *waves goodbye* *wonders if DS gets it now* *inserts sigline* *bolts for the fridge*