Fatbike tuning guide: find exactly what fits
Pick your model, check your motor plug colour (red or black) and see straight away which tunable controller and display fit your fatbike.
Choose your fatbike
Do you ride an Ouxi C80 Mini, C63 Mini or QMWheel V20 Mini? Those models cannot be tuned: there is no tunable controller or display for them. They stay limited to 25 km/h.
Check your motor plug
One thick motor cable comes out of your motor (in the rear wheel). Follow that cable to the first connector and gently pull it apart. The colour is on the inside of the motor plug: red or black. Tap your motor plug colour below:
Not sure if you have a 250W or 500W motor? Compare your brake disc with the motor in the rear wheel: is the brake disc bigger than the motor? Then you have the small 250W motor. Is the motor bigger than the brake disc? Then you have the 500W motor.
This fits your Ouxi V8
Displays fit both motors (250W and 500W). The motor plug colour only matters for the controller.
Check your motor plug
One thick motor cable comes out of your motor (in the rear wheel). Follow that cable to the first connector and gently pull it apart. The colour is on the inside of the motor plug: red or black. Tap your motor plug colour below:
Not sure if you have a 250W or 500W motor? Compare your brake disc with the motor in the rear wheel: is the brake disc bigger than the motor? Then you have the small 250W motor. Is the motor bigger than the brake disc? Then you have the 500W motor.
This fits your Ouxi C80
Displays fit both motors (250W and 500W). The motor plug colour only matters for the controller.
No motor plug check needed
Check your motor plug
Applies to: V20, V20 Pro, V20 Cross, S20 and S20 Pro.
One thick motor cable comes out of your motor (in the rear wheel). Follow that cable to the first connector and gently pull it apart. The colour is on the inside of the motor plug: red or black. Tap your motor plug colour below:
Not sure if you have a 250W or 500W motor? Compare your brake disc with the motor in the rear wheel: is the brake disc bigger than the motor? Then you have the small 250W motor. Is the motor bigger than the brake disc? Then you have the 500W motor.
This fits your V20 / S20
Displays fit both motors (250W and 500W). The motor plug colour only matters for the controller. Newest generation V20 with NFC screen? Pick the NFC display.
How to check which motor plug colour your fatbike has
All you need is a pair of wire cutters and it takes a minute. The colour is on the inside of the motor plug, so you'll need to pull it apart. That's fine: it won't damage the plug.
-
Go to the rear wheel
Put your fatbike on its stand. The motor is in the rear wheel, and one thick cable comes out of it: the motor cable.
-
Follow the motor cable to the plug
The motor cable runs along the frame to the first plug. It's usually held in place with two cable ties. Cut the first one.
-
Cut the second cable tie too
Now the plug hangs free and you can get a good grip on it.
-
Hold the plug on both sides
Hold it by the thick plug housings, not by the thin wires.
-
Pull the plug firmly apart
It's a tight fit, so don't be afraid to pull hard. The plug won't break.
-
Look at the inside
Where the pins stick out you'll see the colour: red or black. That's your motor plug colour.
Which colour did you see on the inside?
For your Ouxi V8 / Ultra (change the model at the top)
For the GT-2000 there's no need to check the plug: there's just one controller and it always fits.
Tuning your fatbike: how to pick the right parts in one go
Want to tune your Ouxi V8, V8 Ultra, C80, C80 Max, GT-2000 or QMWheel V20, V20 Pro, V20 Cross, S20 or S20 Pro? Then you only need to know two things: which model you ride and, for the controller, which motor plug your bike has. This guide tells you both in under a minute, so you can order with full confidence that the part fits.
Tunable controller or tunable display?
A tunable controller is the heart of the upgrade: it replaces your standard controller and unlocks the higher top speed. A tunable display (such as the HC80, M5 or H6C) lets you adjust the speed settings, includes a killswitch and, on the NFC versions, lets you lock the bike with a chip. Displays fit both the 250W and the 500W motor, so you can never go wrong there. With the controller, the motor plug colour has to match.
Red or black motor plug: this is how it works
Every fatbike motor has one thick motor cable coming out of the rear wheel. Follow it to the first connector and gently pull it apart: the colour is on the inside of the motor plug, red or black (you won't see it from the outside). On the Ouxi V8 and C80, a red motor plug means the 250W motor and a black motor plug means the 500W motor. On the QMWheel V20, V20 Pro, V20 Cross, S20 and S20 Pro it's the other way around: black is 250W, red is 500W. The GT-2000 has just one controller type, so no check is needed there.
Recognising a 250W or 500W motor
Can't tell from the motor plug? Compare the brake disc with the motor in the rear wheel. If the brake disc is bigger than the motor, you have the small 250W motor. If the motor is bigger than the brake disc, you have the 500W motor. Still in doubt? Send a photo via WhatsApp and our specialist will confirm which parts you need.
Ordered today, tuning tomorrow
Order before 23:59 and your parts arrive tomorrow. Prefer to browse everything? See all tuning parts or all fatbike parts. Please note: a tuned fatbike may only be used on private property.
Read more: everything about your motor cable colour and which controller goes with it
Which colour motor cable do I have? All about red and black motor plugs on fatbikes
Want to tune your fatbike? The first question you need to answer is: which colour motor plug does my fatbike have? The motor cable (you'll also hear it called the motor plug, motor connector or motor lead) is the thick cable that comes out of the hub motor in the rear wheel. On the inside of the plug, where the pins are, it's either red or black. That colour tells you which motor is in your fatbike, and so which tunable controller fits. Order a controller with the wrong plug colour and it simply won't fit.
Red or black motor plug: what does the colour mean?
The motor plug colour tells you how powerful the motor is, but which colour means what depends on the brand. Ouxi V8, V8 Ultra, C80 and C80 Max: a red motor plug means the 250W motor and a black motor plug the 500W motor. QMWheel V20, V20 Pro, V20 Cross, S20, S20 Pro and V29 Pro: exactly the other way around. A black motor plug means the 250W motor and a red motor plug the 500W motor. Ouxi GT-2000: nothing to check here. There's just one type of controller and it fits every GT-2000. Got a different model? Send a photo of the inside of your plug via WhatsApp and we'll tell you which controller you need.
How to check your motor cable colour in 1 minute
Put your fatbike on its stand and find the thick cable that comes out of the motor in the rear wheel. Follow that cable along the frame to the first plug. The cable is usually held in place with two cable ties: cut them with wire cutters. Hold the plug on both sides by the thick plug housings (not by the thin wires) and pull it firmly apart. It's a tight fit, but it won't break. Now look at the inside, where the pins stick out: red or black. That's your colour. Then push the plug firmly back together and put a new cable tie around it. See the step-by-step guide with photos.
Which tunable controller goes with which colour?
The rule is simple: the controller's plug colour must match your motor's plug colour. Red motor plug on your fatbike? Then you need the tunable controller with a red motor plug. Black motor plug? Then the tunable controller with a black motor plug. All our controllers have the colour in the title. For the Ouxi V8 and C80, both versions are tunable up to 50 km/h. For the QMWheel V20 and V20 Pro, the red version (500W) goes up to 45 km/h and the black version (250W) up to 32 km/h. The V20 Cross and V29 Pro have their own controller with a red motor plug. Pick your model and your plug colour at the top of this page and you'll see the right part straight away.
Does the plug colour matter for a tunable display?
No. Tunable displays such as the HC80, M5 and H6C fit both the 250W and the 500W motor. The motor plug colour only matters when you're choosing a controller. If you only want to tune or replace a display, there's no need to check the plug.
Common mistakes when checking the motor plug
Looking at the outside. On almost every fatbike the outside of the plug is black; the colour is only on the inside, by the pins. Following the wrong cable. The motor cable is the thickest cable coming out of the rear wheel, not the brake cable and not the thin cable to the pedal sensor. Pulling on the wires. Always hold the plug by the thick housings. Leaving the cable ties on. You won't get the plug apart with them on; cut them and put a new one on afterwards.
What if I order the wrong colour by mistake?
A controller with the wrong plug colour won't fit your motor, so you can't connect it the wrong way by accident. Not sure before you order? Send a photo of the inside of your motor plug via WhatsApp and we'll confirm which controller you need, free of charge. Already ordered and it turns out to be the wrong colour? Drop us a message and we'll sort out the right version for you.
Summary: which colour motor plug do I have and which controller fits?
Red motor plug on an Ouxi V8, V8 Ultra, C80 or C80 Max = 250W motor = tunable controller with a red motor plug. Black motor plug on an Ouxi V8, V8 Ultra, C80 or C80 Max = 500W motor = tunable controller with a black motor plug. Black motor plug on a QMWheel V20, V20 Pro, S20 or S20 Pro = 250W motor = tunable controller with a black motor plug (up to 32 km/h). Red motor plug on a QMWheel V20, V20 Pro, V20 Cross, S20, S20 Pro or V29 Pro = 500W motor = tunable controller with a red motor plug (up to 45 km/h). Ouxi GT-2000 = one controller, no check needed. Please note: a tuned fatbike may only be ridden on private property.
Frequently asked questions
How do I know if my fatbike has a red or black motor plug?
Follow the thick motor cable that comes out of your motor (in the rear wheel) to the first connector and gently pull it apart. The colour is on the inside of the motor plug: red or black. You won't see it from the outside. Not sure? Send a photo via WhatsApp and we'll check it for you.
Do I have a 250W or a 500W motor?
Compare the brake disc with the motor in your rear wheel. Brake disc bigger than the motor = small 250W motor. Motor bigger than the brake disc = 500W motor. On the Ouxi V8/C80 the 250W has a red motor plug and the 500W a black motor plug; on the V20/S20 it's the other way around.
Does the motor plug colour matter for the display?
No. Tunable displays (HC80, M5, H6C) fit both the 250W and the 500W motor. The motor plug colour only matters when choosing a controller.
Am I sure this part fits my fatbike?
Yes. Every part in this guide is matched per model and per motor plug. Pick your model, check your motor plug and the parts shown are guaranteed to fit. Still in doubt? Our specialist confirms it for free via WhatsApp.
Is a tuned fatbike street legal?
No. A tuned fatbike may only be used on private property. On public roads the legal speed limits apply.
Which controller do I need to tune my fatbike?
That depends on your model and your motor plug colour. Ouxi V8, V8 Ultra, C80 and C80 Max: red motor plug = 250W motor, black motor plug = 500W motor. QMWheel V20, V20 Pro, V20 Cross, S20 and S20 Pro: black motor plug = 250W, red motor plug = 500W. Pick your model and plug colour above and you'll see straight away which tunable controller fits. The GT-2000 has one controller type.
Can the motor plug break if I pull it apart?
No. The plug is a tight fit, so you can pull firmly. Hold it by the plug housings (not by the wires) and pull straight apart. Then simply push it back together; the pins only fit one way.
Do I have to cut the cable ties to see the colour?
Usually, yes. The motor cable is often held to the frame with two cable ties, which stop you pulling the plug apart. Cut them with wire cutters and put a new cable tie on afterwards.
Which controller fits the QMWheel V20, V20 Pro or S20?
Black motor plug: the tunable controller with a black motor plug (250W motor, up to 32 km/h). Red motor plug: the tunable controller with a red motor plug (500W motor, up to 45 km/h). For the V20 Cross and V29 Pro, the red-plug controller is listed separately in the guide.
Which controller fits the Ouxi V8, V8 Ultra, C80 or C80 Max?
Red motor plug: the tunable controller with a red motor plug (250W motor). Black motor plug: the tunable controller with a black motor plug (500W motor). Both are tunable up to 50 km/h; only the plug colour has to match.
Can't find your question? See all 132 answers on our help page.