I bought a Hammerhead 150 last year and recently started working on it. I replaced the stator, starter, CDI, , started relay, adjusted the valves and changed the oil to Mobil 1 10w-40 full synthetic in order to get it to run. The auto-choke is missing the needle that blocks the extra fuel off, so I know that's a problem but it will drive in reverse at a fairly decent speed but forward barely budges, you can just feel it kind of nudge the kart. Was wondering if anyone knows what could be the problem? What would adjusting the linkages do? Thanks guys.

 

is it going into forward all the way? that should be a centrifugal clutch style set up. i think. this is the go kart, right? should be similiar to my roketa 150cc kart. does the clutch area smell burnt or is the parking brake set/stuck?

 

Reverse is going to be geared lower. Take the CVT cover off, check your clutch, which might be slipping. You could also have an issue with your rollers. Your best bet for good advice on those chinese buggies is to go to buggynews.com.