[Rage]

ok i have been searching thread after thread for a few hours now an can't find a fix to my problem. so my problem is my neighbor has a 50cc scooter his son sold parts off of it an he wants me to fix it. i put a new carb, new clutch, new spark plug, new coil, new cdi, and new stator on it. an i adjusted the valves at .004, the problem i'm getting now is the battery is at about a 13 volt charge but acts like its dead when trying to crank the scooter. i checked all the wiring an grounds an its all good. i am able to kick start it. my other problem is when its running there is very little power getting to the back tire. i took the variator off an looked at the rollers an they are fine no flat spots at all but it does not want to engage till its at almost full throttle. i can keep the clutch from spinning with my hand by holding it at idle an accelerating to full throttle. i got on to try to ride it at the max speed it took me was 10mph an it took some time to get up to that. i'm thinking low engine compression but i don't have the tools to test it. any suggestions? also all the vacuum lines are good an there is no intake air leak.