Sport_Pilot

I suspect your homemade venturi would work somewhat better than the TT one. Unless the TT venturi is smaller. Yours is longer so it would also work better as a velocity stack. I would run it first. I wouldn't be sure till I put it in the air. You can run the TT on the bench well without the venturi but in the air is another matter.

markisenberger

THE TT .54 FOUR STROKE IS GARBAGE.

Sport_Pilot

The only complaint I have heard of about this motor is about the air bleed carb. Let me see if you have this right. You bought a .54 4C for a plane made for a .70 4C and blame the engine for poor performance. Then it kicks the prop when run lean (something in common with almost every 4C) and never try lower nitro and this is also TT's Fault?

Sport_Pilot

The only complaint I have heard of about this motor is about the air bleed carb. Let me see if you have this right. You bought a .54 4C for a plane made for a .70 4C and blame the engine for poor performance. Then it kicks the prop when run lean (something in common with almost every 4C) and never try lower nitro and this is also TT's Fault?

Instead of calling good products trash, why don't you ask for a solution instead? I have little patience for venting for venting sake.

XJet

I'd actually rather have a good airbleed carby than a bad twin-needle one. For example -- my TT61GP (with its airbleed carb) idles and transitions a damned sight better than my ST90 with its badly designed twin-needle carb.

Ultimately both carbs (air-bleed and twin-needle) achieve the same result -- maintaining a relatively constant air/fuel ratio at different throttle settings.

In fact, I'd wager that, give a 4-stroke's greater ability to handle a slightly rich mixture, people would be hard-pushed to tell the difference if they were flying the differnet types of carbs on such an engine.

I fly 3D (where good carburetion is *essential* for proper transition and reliable operation at partial throttle settings. I'm biffing the stock ST90 carb and replacing it with an airbleed unit of my own design which (believe it or not) is *miles* better.

markisenberger

Sport Pilot, I'm sure this will be yanked off the forum soon, but I just had to tell you: You’re the Cliff Claven of RC Universe.

The TT .54 throws props because it's an inferior product. I thought of you when I was reading this month’s Model Airplane News and the engine advice column devoted a whole question specifically to the Thunder Tiger .54 and its propensity for prop throwing. I also thought of you when I read the engine advice chapter in the Radio Control Airplane Engine Guide, published several years ago by the editors of Model Airplane News, which ALSO had a section on the exact same problem with the EXACT SAME MODEL ENGINE!!!

Someday, if I try really hard, I’ll be as wise as you… Until then, I’ll keep reading your informative posts and learn from them, hoping to one day be as wise as you. And I promise to never call a good product trash, or vent just for venting’s sake.

XJet

Geez, that must mean that My Saitos and at least one OS I've seen throw props are also inferior engines.

Hell, I don't know a single 4-stroke that won't throw a prop if it's tuned or operated incorrectly.

A bad workman... ?

I believe what I experience myself ahead of what I read by way of some third-party.

Maybe the 54 does have a propensity to throw props -- so what? Just make sure you stay away from that part of its operating envelope. Hell, I had a TigerShark 56 that was *far* worse than any of my 4-strokes when it comes to backfiring and tossing props. And I was running it on 5% nitro.

Sport_Pilot

I haven't read a MAN or any other rag for a number of years now, so I don't know about that article, but I do know most any 4C will throw a prop if run lean. That is why most have a collet type prop nut. I have never owned a TT .54 4C but have seen several at our field and the only complaint I have heard is the air bleed carb and one that leaked air past the main needle. There have been posts about that engine having the cam off one tooth from the factory. I don't know if it was a batch of them set incorrectly or if it is a continual problem, but this could also cause the prop to be thrown off.

ABORH

I had the TT .54 FS in a Koysho Super Stearman. This would haul the plane around OK. I think people would say that it flew like a scale Stearman. It was definitely not a 3D plane. I enjoyed the plane much better with a 70 FS. I have since put it in a .40 size Staudacher. It is much more at home there. It is inverted. I opened the air-bleed idle screw to compensate for the rich fuel mixture from being inverted and it runs just fine.

bigedmustafa

My Feedback: (2)

"Thunder Tiger engines are cheap O.S. copies." "You can't get parts for Thunder Tiger engines." "Thunder Tiger is a stupid name designed to rip off the brand image of Thunder Power or Super Tigre or Kellog's Tony the Tiger." "Thunder Tiger engines are constructed from spent uranium rods and they weight 8X more than any other glow engine of similar displacement."

If you don't like Thunder Tiger engines, then don't fly them. If you want to continue spreading myths about Thunder Tiger products, that is also your right. I for one am simply glad to have variety and choice in the marketplace.

Any hobby store with a reseller account through Ace Hobby should be able to get you any Thunder Tiger engine part you need. If they're like my local hobby store, you'll need to give them the part number and then spell A-C-E_H-O-B-B-Y very slowly for them.

If you don't have a local hobby store and you need Thunder Tiger engine parts, try the following Thunder Tiger/Ace resellers:

http://www.thundertiger4u.com

http://www.ehobbies.com

http://www.infinitehobbies.com

Don't see the part you need? Call or e-mail customer service and they'll get it for you if they can lay their hands on it.

For those who don't know, Thunder Tiger also makes really nice aircraft ARFs. You should consider the Thunder Tiger September Fury ARF, Giles 202 .40 ARF, or Giles 202 1.40 ARF the next time you looking for a fantastic scale airframe for your O.S. Max or Saito engine.

P.S. - I don't know for certain, but I heard that Thunder Tiger's Ripper brushless motors are just cheap knock-offs of O.S. Max's brushless outrunners...

Dauntae

LOL bigedmustafa Great post, I like it LOL

pcbprotool

Is this uncommon, or strange that the high speed needle valve is on the same side as the exhaust?? I purchased a new Thunder Tiger .91 4c in an auction and went to start it this weekend. I found it very touchy to adjust the needle valve with the echaust so close. Is there any way around this and how do you adjust the valve if the engine is mounted on its side? your adjusting under the plane... a very strange place to put a needle valve... It did run very smoothly and idled nicely, have yet to put a tach to it but am please with it's performance. I have a 13x8 prop on it, and am running it low to mid speeds not spending much time at full rpms.

thanks ahead of time for your replies...

Beef

My Feedback: (10)

pcbprotool: Remove the two screws that hold the carb to the backplate, then flip the carb 180 degrees around. Why they are installed this way at the factory is beyond me. I've had to flip OS and Saito in the past as well.

pcbprotool

I looked at doing that but there is what looks like the idler screw is in the way. If turned it would be facing towards the cylinder head and be unable to adjust... or am I mistaken and it's only a set screw?? I don't do alot of engine fine tuning etc.

Thanks again

PCBPROTOOL

Beef

My Feedback: (10)

That screw directly on the back of the carb is the rotor retention screw and it has no adjustment. The idle stop screw is on the top of the carb nearest the needle valve. It would still be accessible with the carb flipped, but I've never had a use for one anyway.

pcbprotool

I've run two tanks of fuel through my .91 tt and am wondering if I can still put loctite or thread lock on the rocker cradle. And second what and where is the rocker cradle... I have the manual so can someone direct me to the part so I can thread lock this before it's too late..

Thanks,
pcbprotool

Sport_Pilot

If you open the rocker cover, the rockers are connected to the cradle which has one screw in the center of the cradle, between the rockers and valves. Unscrew that center screw and put locktite on it, torque it down, and then readjust the valves. It's not too late.

martin3737

What is the thread size for the Rocker Arm Cover bolts? And what is the bolt length(s)?

Thanks