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Razor Crazy Cart Upgrade 1000W

Hey guys,

I just scored myself a crazy cart, currently it is modified and runs a 36v controller and 3 12v sla batteries. It was modified by a previous owner, I believe this one is a series 1 or 2.

The first day I got it, it was great. Went to ride it today, and it seemed incredibly sluggish, almost didnt move me forwards. I'm 70kg and this is just a regular crazy cart (not XL) running a standard motor that has been recabled. It smells like burnt copper now, so I suspect the motor has burned out. 

I'm now looking for a bit more speed, ideally 30+ km/h and enough torque to get me up some 15 or so degree inclines, as it really struggled to pull my weight on even a slight incline. I was thinking about trying to go for a 36v 1000w motor, so I could still use the existing controller and hopefully just have to upgrade the motor, and possibly get some better sla batteries, as the current one's amp hours are terrible (something like 5ah). 

As I'm new to this modification scene, any advice, tips or guidance would be fantastic! Looking forward to many happy runs on the crazy cart. Even on the 15 minutes of use I got out of it, it was a heap of fun. 

1 person likes this idea
The original controller could be used with a 36 Volt 1000 Watt motor, however, it will most likely not provide the new 1000 Watt motor with the same amount of power that a 36 Volt 1000 Watt controller would, so the top speed could be faster and hill climbing ability better with a 1000 Watt controller.

Installing a battery pack with a higher Ah rating should also help with the amount of power that the motor has. A 5Ah battery pack is quite small and will limit the amount of current when used with a 1000 Watt motor. For a 36 Volt 1000 Watt motor, we recommend using 15Ah batteries or higher.
Looking into things a bit further, the plan I want to do is a 36v 1000w motor (I believe the currie motor can be made to fit?) And a 48v controller so I can use the 4 12v batteries, which 3 power the motor and 1 currently powers a light bar on the front, that I have in place at the moment (currently has 4x 12v 9ah batteries, which I may upgrade to 12ah or so if I can fit them in the stock location). Other than a 48v controller, 36v motor, which batteries can I get that I can use in the original space? The current batteries are mounted width ways, standing upright, so the (terminals are at the top facing towards you if you're sitting behind the cart). Ideally id like to do as little modification to fit the batteries as I can. What else other than the controller, motor and batteries will I require to make it fit a normal crazy cart? (Ie. Not the XL one) Mine is a series 1-4 if that helps. Thanks again!
A few of our customers have successfully installed the 36 Volt 1000 Watt Currie motor on their Crazy Carts. There are a couple of different Crazy Cart front forks versions though, one version is made from stamped plate steel and the other from welded steel tubes. So we recommend to take inside fork measurements and compare them to the motor dimensions to make sure that the motor will fit before attempting the modification.


We are not sure about what size batteries other than the originals will fit in the Crazy Cart's battery tray.

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