Nothing but a twin is going to have the lightness of a Phazer feel, the only 4 stroke with less weight is the 600 ace currently and maybe the Cat with the 65hp Kymco. Only way to get lighter with more HP is a BIG twin. Any triple or four would require replacing cheap steel chassis compents with expensive aluminum or magnesium which defeats the purpose of a "value" or "entry" level sled. Sadly I think we will see lower output triple in the Vipercross 2.0 chassis which will replace the Phazer. I'd love to see a 100hp twin and sub 475# and either a 600cc with gear reduction or a 850-ish 8800rpm twin could reach that. For Yamaha to build that there would be a need though and I haven't seen ANY sleds under 600cc lately on the trails unless it's an old trailing arm sled. Heck, out of 300+ sleds I seen yesterday I was the ONLY Phazer, seen quite a few Apex,Vector, Vipers along with 2 Polaris 660 turbos