I have similar problems with my razor mx350.

Have you tried removing plastic chain guard and making sure chain is not off track i had this problem and that is all it was.

#1 check your power voltage on your batteries #2 you need to check the power to the electric motor - #3 possibly replace the control module - #4 possibly replace the throttle

I need help! My son mx650 is charged, but won’t run. Put weight on it won’t move but lift rear tire off ground and runs full throttle

MX350 is a 24V bike.
You could change the gearing by replacing the sprockets, or you could replace the electric controller and upgrade to 36V, but you probably would be better off getting a bigger model, like the MX500, as this uses 36V already and the higher voltage allows for higher motor rpm.

Check that the lights on the throttle battery gauge show green. Lift the rear wheel off the ground and apply throttle and watch the lights. If the battery voltage drops under this load, indicated by the light changing to yellow or red, then it is likely the batteries are low in capacity and need replacing. Most battery shops will load test the batteries free of charge to confirm.
If the batteries test OK then it may be a bad connection between the batteries, fuse, switch and controller may also cause the voltage to drop under load,

sounds like your battery need s replacing as the voltage is dropping under load.

If it was working before it sat, then it is almost certainly the battery (these kinds of batteries suffer if sitting and not fully charged). If you had one, or could borrow a voltmeter, you could check the batt. Also, lots of car part places like NAPA can test batteries for you.

Hope that helps

This is not a gasoline operated right? So the problem may lies beneath the control panel or motor it self.

ITP tires

I would take it to a shop only because the tire has to be on almost perfect so there is no wobble.They have the proper equipment to make sure it is aligned properly.If you are going to go around 40-50 mph alignment is critical.Even jumping moguls and turning alignment is critical.

Hi there,

First of all you try removing wires from the battery and check battery may be it gone.
also check wires are connected properly to the throttle.

Post back result for more help.
Good Luck!!

Thanks