Standard guage? 

Polaris claims 140. But I feel I can't get it because you can't run it in 91 non e mode. Probabily only making 130 ish, since you are forced to set it at 87 octane fuel, if fuel has e in it. 🤷🏽‍♂️

I think thats pretty accurate.   There seems to be 650s everywhere.    My buddy just bought a brand new 25 XCR650 for $16600 a couple of days ago.       

What hp is the 650, 135 ish?

I bought two stroke kept 900 ace. Polaris chassis is made for a light weight motor. Four stroke version don't handle anything like 2 strokes do. 650 is a good choice.