When it comes to top speed, there are mainly 3 factors that control it in mini-bikes and Go-karts, they are, Gear ratio, Tire size, and Engine’s rpm.
A stock Coleman CT200U has a 10:1 gear ratio, has a 19″ tire diameter, and 3600 as max RPM.
Therefore, theoretically, a stock Coleman CT200U has a top speed of 20mph, as can be seen by using our calculator down below.
But, of course, that is a theoretical value and in reality, there are a lot of slippages and the weight of the driver is also an important factor, practically the Top speed of stock Coleman CT200U is between 19-22 mph.
What engine is on the Coleman CT200U?
As you might know, the engine is what powers your mini-bike or any other gas-powered or electric-powered vehicle. Therefore it is a major factor in determining how fast your minibike can go.
The Coleman CT200U uses a Hisun 196cc motor that produces 6.5 hp power and is governor restricted to 3600 rpm out of the box.
It’s very similar to the $100 predator 212 engine but with slightly less displacement.
One major difference is the shaft size, the Hisun 196cc motors come with a 5/8″ shaft instead of a 3/4″ shaft that is common in other small engines.
Coleman CT200U top speed without Governor
Originally the CT200U comes with a throttle stop screw and a Governor that limits the minibike from exceeding 3600 rpm, or 20 mph.
The throttle limiter screw prevents you from going full throttle, the screw is welded so you will need to grind it with a Dremel.
Removing the throttle screw will get your Coleman CT200U to 25 mph (give or take 2-3 mph depending on your weight).
The Governor in the engine limits the engine to only make 3600 rpm at max. If you remove the governor, your engine can potentially make up to 4500-5000 rpm.
Removing the governor will make your Coleman CT200U’s top speed 30 mph (give or take 2-3 mph depending on your weight).
Governor can be disabled by either completely taking out the governor gear or using a zip tie to zip the spring that brings the governor into action.
You can easily find step-by-step tutorials for both methods on Youtube. It’s not really hard to do and costs you nothing.
Note: Engine parts such as Flywheel and Billet rod can fail at high RPM which can be dangerous, it’s recommended to upgrade to a billet rod and a billet flywheel once you remove the governor.
How to make a Coleman CT200U faster?
Apart from removing the governor, there are a lot of modification parts available on the market for Coleman CT200U that can be found on GoPowerSports and OMBWarehouse.
By far the easiest method to gain speed is swapping out your clutch for a 30 series torque convertor. You won’t need to do any internal work on your engine for this.
What will a torque converter do?
The Coleman CT200U comes with a clutch that is geared at 10:1. So if your engine is spinning at 3600 rpm, your wheels can only rotate at 360 rpm.
If you want to go faster, you will need those wheels spinning faster.
Simply changing the gear ratio with a clutch still on isn’t a good idea either. Why? Because this mini bike has 19″ wheels, it requires the torque that is provided by 10:1 gearing.
If you increase the gearing with a clutch, the clutch will fail.
A torque converter solves this problem, a minibike with a torque converter doesn’t have a fixed gear ratio.
Torque converter works in such a way that the gearing is low at low speed and high at high speed. Therefore giving a good take-off acceleration and a higher top speed.
The top speed of a mini bike with a torque converter will depend on the sprocket used.
You should be able to achieve a gear ratio of 6:1 at the top end, without causing much damage to the torque converter.
That gear ratio will get the mini bike to go at 35 mph (with Governor) and 42 mph without Governor.
Note: Most 30 series Torque converters available in the market have a 3/4″ driver bore. CT200 nowadays have a 5/8″ shaft and older versions used to have a 3/4″ shaft (measure your’s to be sure).
If you have a 5/8″ shaft then make sure to either buy a Torque converter with a 5/8″ driver or get a 3/4″ crankshaft for the engine.
Installation tutorials are available on the GoPowerSports youtube channel, they also sell Torque converter with a 5/8″ driver.
Internal Engine Mods
Gearing properly and using a torque converter can take you to a certain limit, but if you want to go crazy on speed, you’ll need to have a more powerful engine.
You can either get a new engine that produces more power or modify your stock engine.
A lot of people get a $100 Predator 212 if they’re planning on modifications that is because of the vast number of options for performance parts available for Predator 212.
A stock Coleman CT200U engine also has a lot of performance parts available online, mostly on OMBwarehouse and GPS.
You can go as high as 6500-7000 rpm with performance parts, if you couple that with a torque converter with top-end gearing of 6:1, the top speed can be as high as 70 mph.
Please note, you really do not need to be going to such high speeds, it can be dangerous for you. The 30-40 mph top speed with a good take-off provided by Torque converters is safe and fun, we recommend not making extensive mods.