ORIGINAL: DBCherry
dydx,
Here's a couple numbers for you to aid in conversions.
Gallon = 3.79 litres
Ounce = 29.57 cc's (liquid volume)
Ounce = 28.35 grams (Mass or weight), yes this one's confusing for us too.

Pound = 0.454 Kilograms
So the typical trainer will weigh in at around 2.5 kilograms and be powered by a 7.54 cc engine. It will carry about 236 to 295 cc of fuel for flights of approximately 10 to 15 minutes.
What? After all that effort doing the conversions and you forgot to change the time to metric?