# New user, need help w/ Razor mx650



## tykenfitz (Nov 24, 2009)

So I picked this ting up at a garage sale for $12.50 and figured that if I couldn't get it working the parts i could get off it would be worth it. I'm really good at fixing gas engines but have never touched an electric one in my life! Now, I'm hell-bent on fixing this so I can give it to my bro for xmas. I fixed all the stuff I know about, flat tires, replaced brakes, removed rust, etc. but I cannot get the stupid motor going.

I think the batteries are working, there are 3 12v batteries and the socket coming out of them reads 31.6v on the multimeter, 4.4 volts less than expected is that ok? I think the motor works cuz I hooked it up to a 19v drill battery ( bad idea, wires got crossed and started smoking) and the bike lurched forward. 

So I think the problem is the controller. I see it has a connector for the throttle, 1 for each brake and 1 in for the battery, 1 for the charger, 1 for the on/off switch and one going to the motor. 

I hooked the multimeter to where you should plug in the motor and it read about 2.8v and when I throttled it the voltage went down.  That can't be right, could it? should there be like 30-36V going to the motor?

Thanks in advance for your help


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## mxmtech (Apr 21, 2009)

Good score.
Have you disconnected the brake wires? The brakes disable the throttle.
Do you have the charger? The voltage is very low, should be up to around 39 volts on a full charge.
You could disassemble the battery and charge each 12 volt battery separately and test them.
The controller might be shutting off for low voltage.
Does the throttle have a set of lights that indicate the state of charge?
Mine lights up 4 lights for a full charge down to one for a depleted battery pack.
Have you downloaded the service manual?
You didn't mention the fuse, did you check it with an ohm meter?


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## ngrimm (Oct 19, 2007)

I assume the controller uses pwm so checking for voltage on the connector without the motor connected may not tell you anything. The controller probably switches (pulse width modulates) the ground path to the motor and battery positive is connected to the other side of the motor. I would first check to see if the motor is getting the positive.


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## fleebell (Jan 5, 2010)

The batteries are fried. Those little batteries are only good for about 1 years use to begin with. 

I've recycled a number of small e-scooters and a few of the small electric pocket bikes from the trash and 99% of the time the batteries have sat for months with no charge by the time I get them...The batteries sulfate up and are ruined and then it's time for new ones. 

Most of the time the bikes stopped being used because the charger died (I've asked) and when mom or dad found out it was going to cost about $50 for a new charger and up to $150 for new batteries, the bike gets stuffed in the garage or shed and forgotten about until it's time to clean out the garage. 

Very seldom have I got my hands on one that had motor or controller problems unless they were left outside in the weather the whole time. 

Lee


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## sunworksco (Sep 8, 2008)

I bought a 200 Razor that was a store display and after about 3 months it won't take a charge.I'm thinking the Chinese put too much lead in the toy!LOL!
I have a couple of 36volt lithium iron phosphate DeWalt batteries that I would like to use but not sure how to bastardize the thing.


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## fleebell (Jan 5, 2010)

sunworksco said:


> I bought a 200 Razor that was a store display and after about 3 months it won't take a charge.I'm thinking the Chinese put too much lead in the toy!LOL!
> I have a couple of 36volt lithium iron phosphate DeWalt batteries that I would like to use but not sure how to bastardize the thing.



Check out this one I converted.
http://www.packratworkshop.com/scooter2.htm
There are more and clearer pictures of it on my site









I've been real happy with it. I put a 500w on the rear and a 250w on the front wheel.... the thing isn't fast (about 15 mph max) but it will climb a 45% angle hill!. It was set up to pull a trailer - I just haven't had time to mount a trailer hitch on it yet.... I've been to busy riding it.
Lee


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## WeinJulie (May 21, 2010)

The MX 650 electric razor scooter is easy and very comfortable for driving.I too own MX650 and it doent trouble me since past 1 year.
Thank You.

http://electricrazorscooter.com/


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## TX_Dj (Jul 25, 2008)

Yup, your batts are dead.

31.6v on a 36v batt = 10.533v per batt, basically completely discharged.

If this is the voltage you see after charging, you need new batteries, you're below the low-volt cut-off for the controller.

A fully charged 36v nominal batt will charge out around 39-40v resting voltage.


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