I have recently ordered my 1st plane, a TT Trainer 40 with a .45 MVVS engine, from a LHS. The engine comes with a tuned pipe rather than a silencer, and I'm a bit concerned that it'll provide too much power for the trainer that i'll be flying. My instructor told me the engine was a good buy, and that it'll scale up with me nicely when I move on to low wings, 3d flying, etc...nevertheless I'm still a bit concerned.

Any words of advice? Does anyone have this setup in their trainers?

Power is your friend don't be afraid of it embrace it often it can get you out of trouble. If it goes to fast for you to stay ahead of throttle back a bit.




When learning to fly RC airplanes you start with a full bag of luck and an empty bag of experience. Your goal is to fill the experience bag up before your luck runs out.

A tuned pipe is a poor choice for a trainer. The pipe is "tuned" generally for top end performance. A sport engine muffler allows good useable performance through a range of throttle from idle to full and the various in between positions. You have a very high quality engine that is poorly matched to the function of training. Can you get a sport muffler for it? If so, that might be an alternative to getting a completely different engine that is more suitable on a 40 trainer.

Sticktickler, thanks for your feedback..especially like the bag of luck & bag of experience sig! =)

and to jim, a friend of mine has offered to lend me a silencer compatible with the MVVS engine..but I'm not sure whether this is the same thing as the 'sports muffler' that you mentioned? and getting a whole new different engine for my trainer is outta the question, I think..budget constraint =(. so i'm pretty more or less stuck with the MVVS power plant for now.

The silencer should do the job. I think it is a matter of semantics, silencer = muffler.

Jim is totally right, the pipe is not for beginners. Used in a lean condition and you can kill the engine in a heartbeat. I have some MVVS engines, all with the tuned silencers and they are great with good midrange and idle as well as awsome top.
I once tried a Macs muffler on my 45 and it fell on it's nose, total flop. If you use a muffler make sure its a MVVS made part.
You have a really good engine that will take time to break in and may be a little cranky for the first half gallon or so, it really will become better the more you use it.
I would pose the Muffler question on the MVVS support side here on RCU, they will make sure you have a proper match.

Hello!
Being the Swedish distributor of MVVS engines I must agree on what Gizmo and Jim says. The MVVS mini pipes (there are two types available for the .40-.49 engines) are not suitable for beginners. Simple as that!
What I recommed for all beginners using .40-.49 engines is the the MVVS ultra quiet silencer (No 3245A). With this silencer you get very low noice levels as well as good power.

No lenghty running in times are needed as all MVVS engines copuld be run directly in the airplane, provided you run the engine a little rich the first 3-5 tanks.
Prop to use would be a 11x6-12x4 APC for best performance in a high winged trainer.

Ok fellas, thanks for the opinions and feedback given. about the MVVS support side on RCU, could someone post the link here?

Well guys, I swapped the TT trainer for a RCM trainer at the last minute..here's a pic of it with the MVVS engine. maidened it last sunday =) engine seems not to be tuned right yet,,keeps dying on me and i get a lot of dead sticks =(

Sounds like you have a break-in problem, a tuning problem, or a fuel problem. Go to the MVVS support pages and do some reading. They have good articles on break-in and tuning, and several posts on what fuels to use.

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Manufacturers Direct Support Forum >> MVVS Support

This is a good place to start.

Remember no more than 5% on the fuel. I also would suggest you turn the silencer so the pressure tap is on the bottom, that will help keep oil from accumulating and running back toward the port(actually had that happed to me on a ST 51).
Bet your low end is in need of a little help and don't totally peak the high end or it will also create a lean condition. Back off several clicks on the high end until you get the hang of this engine.
These engines get much better the more they are ran........

Most training statrs when the plane has been taken up to a safe altitude by the instructor and then throttled back top 1/2 or a bit less. He should tell you to set your throttle to about the same setting and then he will give control over to you. SO, if your are running at half or less, the extra reserve at full throttle isn't going to hurt any thing, its just there if, and when you need it![8D]

Hi!
Part of your problem is due too the fact you have mounted the engine upright ...which makes the tank position too low.I don't think it's an idle problem, or a running in problem, as all MVVS engines throttle perfectly from the first tank...as all other engines do.

Center of the tank should always be inline with the carb when airplane sits horizontal. This is something that every experienced R/C flier knows but few newbies think of.
Fix this by mounting the engine on its side. And remember that MVVS engines have rather high compression , but as you have a blue head engine, 15% nitro is OK! All older type of MVVS engines run best on 0-5% nitro.

Regards!
Jan K
Airracing products