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Need help selecting parts for Razor Quad 500 upgrade

Greetings!  I just built my first eBike and would like to take some of that experience and upgrade the Razor Quad 500 that I have.  It's currently a 36V system with a 500W motor.

I would like to build a 52V (or 48V) LiIon battery; I have about 120 decent 18650 cells on hand to do so.

Does ESP sell the controller and motor upgrade I would need (with an appropriate number of sprocket teeth for what speed we can expect)?  I'm not sure if the thumb controller from the existing Razor would work, does anyone know?

So, it sounds like I need a controller, throttle, and 1000W, 48V motor.  But I have no idea how to find specifics!



The Razor Dirt Quad 500 is such a new model that we have not helped anyone to modify it yet. We carry a 48 Volt 1000 Watt gear motor that you could have a look at on our 48 Volt Motors page. 

The best place to start would be with checking gear ratios and top speeds with different motors and axle sprockets to find a motor and sprocket that will provide the speed that you want the quad to have. We have an online calculator for this on our Top Speed and Gear Ratio Calculator page. 

I did some disassembly and research - it looks like the current 500W gear reduction motor (MY1016Z3) had 25 teeth and the axle has 36. Not sure why but it says 500W on it while that model number usually comes up as 350W.

I don't know how to find out how many RPM that motor current makes... I can't do much more until I know that.  There's a 3-yr old thread from ESP Support that talks a bit about this model:

If I assume 3000rpm, 25 motor teeth, 36 motor teeth, 14 inch tall tire, that's 88mph.  So I'm doing something wrong!

To get the MY1016Z3 motor up to 500 Watts Razor must have ordered them with neodymium magnets. 

Not sure if you want to modify for more speed or for more torque, probably for both. I ran a top speed calculation using our MOT-481000PL 48V 1000W gear motor for a top speed of 20.89 MPH and got a result of an 11 tooth axle sprocket. 

Since the original motor is 500 Watts and the original top speed is 10-12 MPH a 1000 Watt motor geared for 20.89 MPH would have around the same amount of torque as the original motor with the gearing aimed towards the faster top speed. The gearing could be lowered for a lower top speed to increase torque if that is the direction that you want to take the modification in. Here is an example of a gear ratio for increased speed and torque.

And here is an example with increased torque only and the same top speed. 

Just ran another calculation with our MOT-361000B motor which is not a gear motor so it is smaller and got a result of 17.24 MPH with an 80 tooth axle sprocket. 

An 80 tooth axle sprocket would hang fairly low though and lower the amount of ground clearance that the quad has. 

Thanks for the help!  That gets me much closer.  One mundane question: They seem to use a lot of teeth in stock form so I would need too remove links.  Can you normally shorten these chains by driving out a link pin, etc, or do I need a new chain?

Do you have a 48V controller with thumb throttle that would with this this motor and a 48/52V battery?



You can shorten these type of chains by driving out two of the link pins and removing a link. Then you would need a master link to attach the chain back together. 

We have 48 Volt controllers, battery packs, and all of the other electrical parts needed for the modification. We can even make a kit out of the parts with matching and labeled connectors so all of the electronics are plug-and-play with each other. 

The 48 Volt 1000 Watt gear motor has a sprocket for #420 chain which is a different size chain than the original Dirt Quad 500 chain, so if it was installed then the axle sprocket would need to be for #420 chain. That is where it gets a little tricky because the axle is most likely 22mm OD and most #420 sprockets are made for imperial size shafts. So you may need to hire a machine shop to make the sprocket's bore and keyway fit the Dirt Quad 500's axle. 

I would start by checking to see if the MOT-48100PL motor will fit in the Dirt Quad 500. Here is a link to a PDF showing its dimensions:

Thanks!  I'm lucky to have a friend who is an old retired vet and a machinist with a JET mill in his home shop, so he can likely make the sprockets fit.

I'll pull it apart again and take some dimensions, check that motor fits, and get back to you... thanks for the help so far!

I had my son test it out last night in stock form using a GPS speedo.  On flat ground (with old worn lead acid batteries) it currently only musters 8 mph on flat ground and 13.5 max downhill, so 20 would be PLENTY fast as a top speed.  Heck, maybe 15-16 would be smarter.

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