I just got a kymco people-s 5t and we tried everything, new plug new air filter clean carb, new carb, all the transmission parts, adjusted valves, checked ignition, checked compression, we checked everything and came out ok no apparent issue there but still no power, I ran out of ideas I would appreciate any suggestions, bike will start normally and run very slowly may reach 30 maybe 40ks and going downhill maybe 50ks if I'm lucky if going uphill it won't go over 10 I am just 140 pounds please help and thank you, bike has 5000 ks and it is a 2008