First off hi all, glad to be here been lurking around for awhile trying to figure what would be best for me to run, but have a few questions/concerns that i haven't found enough info on yet Let me first list my bike and what i plan on running... 08 Hardrock pro 19" 49cc HS w G4 drive SBP shift kit Now to my questions i live up at 6000ft and wondering how the 4 stroke works in the slightly thinner air? How will it climb up the 13 mile at 8% grade then 3 mile 15% switchbacks, what kinda speeds would i be looking at, pedal assist is no prob I ride down everyday so am wondering if i need a diff clutch or something to disengage for going down or will the SBP freewheel take care of that? (again sorry for being so new to this) And now fit, i used the 9.5in x 8in template and i have about an in on the top left corner where the top tube drops will i be alright or would i need to relocate the carb or something to make it fit? Thanks all for the help!!