MP-250-A scooter not throttling normal

[Deaf250scooter]

Having an issue with my 250cc scooter..

Tho I'm red neck and I dropped in lawn tractor battery in storage compartment because it won't fit small battery tray because I didn't have correct size battery to fit in tray.. One day my Daughter in law borrowed my scooter to go to store. Battery fell out of storage box and yanked main wires which shorted out and smoke billowing out. She contacted me in emergency and I drove my truck with small trailer and my son joined with me. We investigated and turned out it's the battery fell through storage (because storage tray not strong and bumps cause it to crack open. Battery is no good and damaged. Brought it home. I apologized my Daughter in law and it's my fault and it's on me for being Red Neck.

I replaced two 10 guage wires (main Battery wires), voltage regulator (oem was shorted out), ordered new starter (starter got burned out). I ordered correct sized battery that fits scooter's battery tray. (Wires and voltage regulator parted out from friend's junked scooter that have exact same part)

After battery and starter arrived, I put all back together and fired up scooter. It ran but oddly it won't throttle like normal. I warmed up the engine while it's on stand (not kickstand) to allow rear wheel run freely at 3,000 rpm. I noticed that engine started to throttle on it own and having runaway. I tried to throttle down and it would not. It don't make any sense to me because damage only limited to battery, main wires, regulator and starter. Carburetor, vacuum hoses and all those cables are intact,. It appears to me that there may be vacuum leak somewhere in intake.

Anyone know about that? Let me know of solution to this problem.

Thanks!!