Guys I've just purchased a Goldberg Ultimate with a Saito 120S in it.

Firstly I need to know where the CG should be, as I'm not too familiar with bipes, and secondly, what sort of performance should I expect from the saito?

Anything I should look out for? And particular fuel requirements??

With everything attached, the plane should hang level if you put your finger under the top wing, just forward of the aft strut. A little nose low would still be safe, but no tail low!

Sorry, don't know anything about Saitos.

CJ

I'll second CJ's starting CG... As long as you are not further back then 25% mean aerodynamic chord (MAC) you will be fine. On the Ultimate with its positive stagger MAC is the distance from the leading edge of the top wing to the trailing edge of the lower wing. If you set the CG at 25% MAC of just the top wing you are sure to have a safe forward CG. You can then move it back via flight testing to suit your flying style...

The Saito 1.20 should give it great performance. I would use a 16X6 prop for maximum thrust...

I have a 120S in mine. Use a 15-7 prop for unlimited vertical. I use 15% Cool Power. In my humble opinion, the recommended c.g. range is way too far forward. I moved mine about one inch aft of the recommended range. To do this, I had to mount my battery all the way at the back of the tail. It still behaves a little nose heavy. Do an MAC calculation on the recommended range and you'll find its close to 15%. Very conservative.

Still think it's one of the all time great model airplanes. Have fun.

The Mean aerodynamic chord calculation gets a bit complicated with the wing sweep on the ultimate..........

Cool, I'll start forward, and shunt it back till it does what I like

I'm a pattern flyer predominantly, so I'll just set it till it'll fly like a pattern ship!!!

I bought it with an APC 15 x 8 and I've got a bolly 15 x 8, but I'll probably drop some pitch off later in the day so I can get those nice verticals with snaps halfway up