After doing a little research it turns out that the 2.25" Vortech spinner is 1.5 ounces versus 1.6 for the 2.25" truturn. So it's actaully lighter. As I mentioned before, I am a little concerned that I don't see an adapter that uses a jamnut like the trutun's do. I assume that many of you are running only 1 nut on your 4 strokes. This Saito 100 is my first 4 stroke and I keep hearing people say you should use a jam nut on larger 4's. What do you guys think?