I currently have a Super Tigre G90 and I am wanting to replace it with a 4stroke. Which 4stroke would compare to a Super Tigre G90. Its in a Shoestring right now. I find 4strokes more reliable, speedwise, which 4stroke would compare?
Thanks

Try a 120 4 stroke.

That would definitely do it, I wasnt wanting to spend that much money though.

then why ask?

120 or the new Saito 1.25 would be nice

My TT91 4C was comparable ... both were turning a 15x4W at 10,200 RPM ... I found it weird that my G90 was only giving me that sort of performance.

The YS 91 would be comparable. However, it's no longer being made as it was replaced by the more powerful YS 110FZ.

Gonna have to disagree here. I run a G90 in my Shoestring and one of my buddies runs a Saito 100 in his. Darn near identical performance. A 120 is an overkill in size and weight.

Yup I agree...also all Saito engines I have run where excellent! Capt,n

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That's too much prop for a two-stroke .90. Put a 13x8 on both engines and see which one wins that race. <G>

Do you mean comparable in weight or power? Well, G90 is not a power house for its displacement in stock form. Like tIANci said, it's only got the power of TT .91 4-stroke, which happens to weigh the same too. Coincidentally, both these engines like to rev higher with smaller props, so this is about as close as you get for a 4-stroke drop in.

I think YS 91 will be more powerful, and also swinging larger props, like 14x8 to 15x8. For Shoestring you want something like 13x8, and http://www.rcfaq.com/rpmstats/rpmbycc1.htm has a datum of TT .91 swinging APC 13x8 at 10800 rpm, at the bottom of this page.

You can get a TT .91 shipped from Tower for $199 - $30 w/ free shipping until the end of this month, quite a good deal I thought.

Saito 100/125 is going to be much lighter than ST G90 w/ muffler, so it will require some weight shuffling.

I had a supertigre 90 on my funtana for 3 flights. what a turd that was. The 90 barely spun a 13-6 prop. I put a saito 125 on it and it was night and day.The ys 91 should do well. If you go with YS, get the 110, You will be much happier. I agree with seanychen