I have a spiderbox with howhit 150cc gy6. Motor starts right up and has good throttle response, but when you go over 3/4 throttle it cuts out or hesitates ( like it has a short pause then stsrts back up ) and comes right back on. The only time you can give it full throttle without the hesitation is going uphill with a load on it. Any help in this would be greatly appreciated.