I fly an avistar rtf. It flies great with the included 40la engine. I recently installed a supertigre 45 on it. I noticed it lands a little faster and does'nt flair as good with the new motor. I'm assuming it's because of the extra weight of the engine. The 45 weighs about 7 or 8 oz. more. I checked the cg and found that I had to add 5oz to the tail to make it balance. Does this seem like a little too much weight. It does balance ok but I would hate to take off and stand the plane on its tail.

If that's what it takes to balance the plane in the same spot then that's what it takes. It definitely doesn't sound like too much weight for what you are trying to do.

Ken

Thanks Ken,
Guess I just need some assurance before I did it.

You could move the battery pack towards the back You would have to cut out an opening under the fuse, and you would have to lenghten the battery leads. that's how mine is done, this way you don't have too much weight. I also have a OS 46AX another thing was to move the tank back a bit. now it is balance without adding any weight.
I know it's a lot to do but if your fussy you find a way. by the way this plane flys great.

roltech

I have a TT .46 in mine and it balanced perfectly with the battery and Rx just in front of the servo tray.

I had the OS .46AX and I had to add about 4 oz of weight in the tail. I tried to move the battery pack as far back as possibly to cut down on the additional weight. It flew great. Have fun!!!