Understanding a 1200w Chinese buggy

Ok, so it’s not a ebike technically, but it appears to have an ebike style rear motor.

The motor is stamped 1200w-48v

I’m trying to understand the machine as it seems straight forward, but I’ve got some questions I don’t understand.

First question is the voltage. The motor is stamped 48v 1200w. The machine has 4x12v lead acid batteries. The included charger mentions a 58.7v output. This seems higher than I expected, or is this correct?

The actual voltage of the full charged batteries are supposed to be around 50.4 volts because they are lead acid. (12.6v per battery). The machines doesn’t get anywhere near the performance specs it’s supposed to. They claim 12km/h in 1st, 24km/h in 2nd and 36km/h in 3rd. I’m lucky to get 16km/h in 3rd with a fresh charged set of batteries.

Could I swap in a lithium battery for more performance, like 52v-60v or is that a bad idea? If my lithium battery has a bms I’d imagine it should be ok.

Here’s a link to the machine in question.
http://unclewiener.com/product/new-1200w-electric-go-cart-utv-buggy-hlw7182/

Thanks all for your time

Yes you could use a higher voltage battery.
It says the max load is 175 pounds maybe this is for kids?

Looks like a motor that drives both back wheels to me. Not a typical bike setup, but it does not appear to have a differential like a typical golf cart.

Lead can charge to as much as 14v, but anything over 13.5v is as full as it will get.

You can run it on a 52v battery, meaning a 14s that charges to 58v, or 16s lifepo4 that charges to 60v. Most likely its controller has 63v capacitors inside it.

As for performance, it should perk up a lot if you dump the lead. Lighter, and less voltage sag under load when the battery is at its fullest.

You could take some lipos, 13 s, and parallel them with the lead, helping with the sag. 13s will be close to the lead voltage at 12.5v.

dogman dan said:

Lead can charge to as much as 14v, but anything over 13.5v is as full as it will get.

You can run it on a 52v battery, meaning a 14s that charges to 58v, or 16s lifepo4 that charges to 60v. Most likely its controller has 63v capacitors inside it.

You could take some lipos, 13 s, and parallel them with the lead, helping with the sag. 13s will be close to the lead voltage at 12.5v.

Click to expand...

Do controllers designed for lead acid have an LVC? Seems like that would be set somewhere around 46V-48V. If it's a generic 48'V controller, probably no issue.

So I located the speed controller. Photos attached. It says

-DC Brushless Controller
-Voltage DC48V
-Current 33A
-Off Voltage 41V
-Throttle Voltage 1.1-4.2V Reverse

So for LVC, I'm not certain its compatible with Lithium...but the Lithium I'm looking to get would be an ebike battery and they generally have a BMS and their own LVC, right? Or is there something I'm missing if I go for the Lithium swap???

One odd thing is the machine performance is about 1/2 of what it's claimed to be when the battery is at full charge. I'm wondering if there is something limiting the performance???

You can see from my attached image that there is a grey single wire that comes out and back into the controller that is currently plugged in.

Also there is a single yellow/green wire (in the same photo) you can see that is unplugged from the factory. It also goes out and back into the controller.

Any idea what the yellow/green wire would be for??? Just seems odd it goes in/out of the controller like plugging it in changes something...I was hoping that it might wake up the performance as perhaps its in some kind of 'low power mode' or something???

Very finally, I was thinking that perhaps if I bypass the gear selector and just used used the 0-5v pedal to control the power to see if the gear selector is also limiting power. I'm not certain how it's controlling the speed 1, 2 and 3.

Thanks in advance for the advice! This forum rocks.

Well, no way they'd ever lie about the performance. They did not lie really, just did their testing downhill with an 80 pound rider, and batteries that way outperform what they install in it.

But if your lead is not new, its sagging enough for about a 25% loss from what they claim.

Perk it up by running the max lithium voltage it can stand, 14s. Don't rely on controller lvc for cutoff, use a bms, or at least install a voltage display that can let you know when to stop.

The gear selector is not changing any gears, just the power level of the controller. Modifying it won't help.

You could put a 60v or 72v, 40 amps controller in it, which would really perk it up. Enough to quite possibly melt the motor if used continuously long enough, or up a steep enough hill, especially if you weigh a lot more than that 80 pound test rider. What is your weight? No need to actually answer, but if its more than 150, there is part of your performance issue right there.

dogman dan said:

especially if you weigh a lot more than that 80 pound test rider. What is your weight? No need to actually answer, but if its more than 150, there is part of your performance issue right there.

Click to expand...

Yeah that’s what stood out to me, it seems to be designed for kids because of the 175 pound max load.
Also the listing has one of the feature labeled as “ Easy to reach foot pedals”

unclejemima said:

So I located the speed controller. Photos attached. It says

-DC Brushless Controller
-Voltage DC48V
-Current 33A
-Off Voltage 41V
-Throttle Voltage 1.1-4.2V Reverse

Click to expand...

So what would you use this buggy for?

Hi guys.

Thanks for the replies.

Yes, this is not for me. It's for my kids. The machine specs 'minimum 13 years age' on it, so its designed to be more than a power wheels jeep. Though honestly, I have a power wheels 12v running at 18v and its about the same speed lol. That's why I was concerned there is some kind of speed limiting on the 1200w buggy.

The gear selector is not changing any gears, just the power level of the controller. Modifying it won't help.

Click to expand...

I was trying to figure out how the gear selector limited power as it appears to be also hitting a wall at a preset speed making me think that it's limiting voltage for power levels and a pre-determined rpm for speed.

But if your lead is not new, its sagging enough for about a 25% loss from what they claim.

Click to expand...

They are brand new. I just got the machine. Freshly charged. So even at 25% loss, its still another 25% off their claim.

I feel the speed right now is being limited, like the ebike 20mph soft cap that is on most of today's ebikes.

That's why I was hoping there was possibly some speed limiter I could remove. I've asked the company I purchased it from for a diagram showing what each of the speed controller plugs does, as there is a single wire yellow/green stripe that is unplugged.

Thanks for the advice guys

unclejemima said:

Hi guys.

Thanks for the replies.

Yes, this is not for me. It's for my kids. The machine specs 'minimum 13 years age' on it, so its designed to be more than a power wheels jeep. Though honestly, I have a power wheels 12v running at 18v and its about the same speed lol. That's why I was concerned there is some kind of speed limiting on the 1200w buggy.

Click to expand...

Ok nice! I bet the kids love it.
I would try unplugging that gray wire and power on the controller, Maybe that’s the speed limiting wire like on ebike controllers.

Maybe the yellow wire is the fast speed connection and the gray is the slow. Just a guess but I’m not sure why it would be a close circuit like that if it’s not a speed limiting wire.

I would try unplugging that gray wire and power on the controller

Click to expand...

Will give this a go! Would be nice if this was all it was. Seems like something simple IMO.

Thank you!!

unclejemima said:

I feel the speed right now is being limited, like the ebike 20mph soft cap that is on most of today's ebikes.

Click to expand...

If you have a speedometer, then the simple test to see if the speed is locked, is to lift the wheel(s) and test the full throttle speed. If it’s faster than the speed when riding, then the speed is not locked.

Hey guys, just wanted to chime in that yes indeed...unplugging the grey cable opened the taps and now its x2 the speed.

Problem solved! Thanks everyone