The engine is the beating heart of any Coleman mini bike. While other components like the frame, wheels, and controls certainly matter, it’s the motor that determines the power, performance, and personality of the machine. Throughout their over 50 years producing mini bikes, Coleman has used a variety of engine makes and configurations to suit different models.
In this article, we’ll take a deep dive into the motors used in Coleman mini bikes over the decades. We’ll cover engine sizes, specifications, features, and more. Understanding your Coleman’s engine helps select mods, maintenance, and replacement parts. Whether you own a vintage model from the 60s or a new one hot off the showroom floor, the engine determines the riding experience. Let’s explore what powers these iconic American mini bikes.
Early Coleman Mini Bike Engines
Coleman entered the mini bike market in 1964 with their first model – simply called the Coleman 200. This diminutive machine featured a 3.5 horsepower 2-stroke, 98cc Tecumseh engine with manual pull starter and single speed transmission. The little Tecumseh motor established the template for Coleman mini bikes to come.
The following year saw the introduction of the larger 5 hp Coleman Charger 65 model. This popular performance mini bike packed a peppy 2-stroke, 64cc Clinton engine with dual exhaust pipes poking out the rear. The Charger introduced features like a 3-speed transmission and centrifugal clutch that improved rideability.
Throughout the 1960s and into the 70s, Coleman continued expanding their mini bike line using mostly 2-stroke engines sourced from manufacturers like Tecumseh, Clinton, and Kohler for their proven reliability and simple operation. Displacements ranged from 50cc on their junior models up to 197cc on performance variants.
These earliest Coleman mini bike engines established the straightforward, no-frills design and engineering approach Coleman still follows today. Simple, air-cooled 2-strokes motivate Coleman classics from the 60s and 70s.
Rise of 4-Stroke Coleman Mini Bike Engines
Although 2-stroke engines dominated the early days, Coleman began incorporating more 4-stroke engines into their lineup in the late 1970s as emissions regulations tightened. 4-stroke engines burn fuel more efficiently and produce less pollution than traditional 2-strokes.
One of the most popular early 4-stroke powered mini bikes was the 1979 Coleman Omni Go Kart featuring a Briggs & Stratton flathead engine. This torquey motor provided plenty of pep for the full-sized go kart application. Coleman also partnered with Kawasaki in the late 70s to offer a twin-cylinder 4-stroke motor on models like the Coleman Trail 200.
As environmental rules progressed, Coleman migrated mostly to 4-stroke power on their mini bikes from the 1990s onward. These modern 4-stroke motors continue to be the mainstay today. Let’s look closer at the features and technology.
Modern Coleman Mini Bike 4-Stroke Engines
Since the 1990s, Coleman has standardized around using single cylinder, air cooled, 4-stroke engines for the vast majority of their mini bike line:
- Fuel Delivery – Carburetors transitioned to fuel injection over time. Fuel maps optimized for low-end torque.
- Ignition – Traditional breaker points were replaced by electronic CDI ignitions for more reliable spark.
- Displacements – Range from 49cc on youth models up to 212cc high performance variants. 80cc, 100cc, 150cc, and 196cc most common sizes.
- Idle Control – Catalytic converters introduced for lowest emissions models. More require oil injection or premix gas/oil.
- Electric Start – Available on most models in addition to backup kick starting. 12V starter system.
- Cooling – Simple air cooling via fins on cylinder and head. Some motors feature fan assist.
- Construction – Low cost cast iron sleeves and aluminum heads minimize weight.
Modern Coleman 4-stroke engines offer increased power versus old 2-strokes along with better fuel efficiency and reduced emissions. They retainsignature simplicity and durability. Let’s look closer at some key engines powering today’s popular Coleman mini bikes.
KT100 Coleman Mini Bike Engine
One of the longest running Coleman mini bike engines has been the KT100. This trusty 100cc 4-stroke single cylinder motor has powered models like the MB500 and SB100 over many years.
The air cooled KT100 is a carbureted engine with electric start backup. It features cast iron cylinder sleeves for long life and aluminum alloy heads to save weight.
With abore x stroke of 56mm x 50mm, the KT100 displaces 102cc. Power output is approximately 7 horsepower at 7000 rpm. Able to reliably turn high rpms, the KT100 strikes a good balance of torque and top end in a compact, lightweight package.
Simple and robust, the KT100 exemplifies why Coleman chose 4-stroke power. It delivers years of fun with basic maintenance. One of Coleman’s most popular and proven mini bike engines.
79cc Coleman CT200U Engine
The Coleman Trail 200 Utility model (CT200U) features one of Coleman’s smallest 4-stroke engines at just 79cc. This single cylinder motor provides torque focused power tuned for utility rather than all-out speed.
Specifications on the 79cc CT200U engine include:
- 79cc displacement from 43mm x 41.4mm bore & stroke
- 8.5:1 compression ratio
- Approximately 4 horsepower output
- Automatic centrifugal clutch
- Electric and kick start
- Single Mikuni carburetor
Geared for low end pulls and lugging ability, the CT200U motor excels at farm work, hauling, and hunting tasks. It has less zip than sport-oriented Coleman engines but plenty of grunt for jobs. More at home on the work site than racetrack. A favorite utility motor that lasts thousands of hours.
196cc Coleman BT200X Engine
On the opposite end of the spectrum, many modern Coleman mini bikes feature a lively 196cc engine. Models like the Black Max BMXC196, MB200, and BT200X all utilize this robust 4-stroke single.
With a bore and stroke measuring 68mm x 54mm, the 196cc engine is one of the largest single cylinder motors commonly found in mini bikes. Features include:
- Electric and kick starting
- Classic side valve design
- Approximately 10 horsepower output
- Single Mikuni carburetor
- Front mounted 11mm spark plug
- Air cooling via head fins
- Cast iron cylinder sleeve construction
The 196cc engine powers Coleman’s sportiest consumer mini bikes with an emphasis on acceleration and top speed. More peak power than torque focused utility motors. More oriented toward trail riding and fun than work applications. Modern manufacturing processes enhance the motor’s durability and service life.
For a stock mini bike engine, the peppy 196cc Coleman motor delivers pleasing performance with great reliability when maintained properly. A proven design that exemplifies the simple but effective engineering of their engines.
MB200-EX Coleman 212cc Engine
Serious performance enthusiasts know that displacement equals speed in motorsports. For those seeking maximum power from a stock Coleman mini bike, the MB200-EX model features a 212cc engine.
By further increasing bore and stroke to 72mm x 60mm, this engine steps up to 212cc versus the standard 196cc. Features include:
- Electric and kick starting
- Performance muffler and air filter
- Estimated 11 horsepower output
- Single Mikuni carburetor
- Front mounted 11mm spark plug
- Air cooled via cylinder fins
- CDI electronic ignition
The hot rod 212cc provides noticeable gains in torque and high rpm power over smaller Coleman motors. Combined with its manual clutch transmission, the MB200-EX becomes the top performing stock Coleman mini bike you can buy. 212cc equates to higher speeds on straightaways and quicker acceleration off corners. Serious power from a production mini bike.
Aftermarket Replacement Engines
When it’s time to rebuild or replace an old, tired Coleman mini bike engine, aftermarket clones offer cost effective options:
YYK 212cc – Near direct swap for the Coleman 212cc motor at a fraction of OEM cost. Includes electric starter.
Clone 196cc – Affordable copies of the common 196cc Coleman engine. Matching mounting points and components.
Predator 212cc – Hugely popular 6.5 HP engine easily adapted to many older Coleman mini bikes. Electric start available.
Lifan 125cc – Compact 125cc 4-stroke motors for lower cost restoration projects. Both kick and electric start versions.
Aftermarket motors lack official Coleman branding but allow keeping vintage bikes running. Clone engines duplicate OEM specs and fitment while “universal” motors like the Predator require fabrication. But all provide quality, affordable power options.
Optimizing Coleman Mini Bike Engine Performance
Here are some tips to keep your Coleman mini bike engine running in peak form:
- Change oil regularly – always use motorcycle formulated oil in the correct ratio.
- Clean or replace the air filter frequently when riding in dusty conditions.
- Closely follow recommended maintenance intervals for tune-ups, valve adjustment, spark plug replacement, etc.
- Use only fresh 87+ octane fuel with the specified ethanol content. Drain fuel before storage.
- Don’t modify the engine in ways that worsen reliability or durability – avoid “pushing” too far.
- Watch engine temperature and don’t overload/lug the motor too long to prevent overheating damage.
- Install an hour meter if your model lacks one to accurately track maintenance schedules.
- Have all repairs done by an experienced motorcycle/small engine shop to ensure quality work.
While Coleman engines are designed to require minimal fuss, staying diligent with maintenance and avoiding abuse keeps them running strong for years. Follow factory recommendations and tune for your operating conditions.
Common Coleman Mini Bike Engine Problems and Solutions
Even with proper care, engine problems can occasionally arise on Coleman mini bikes:
Overheating – Clean cooling fins, check oil level, fix leaks. Potential head gasket/valve failure if chronic.
Smokes excessively – 2-strokes need decarbonization. 4-strokes indicate seeping seals or bad rings.
Knocks or pings – Use fresh 89+ octane gas. Check valve lash. Potential bearing/rod issue if persistent.
Won’t start – Verify fuel reaching carb, check for spark, inspect air filter. May need carb cleaning.
Cuts out under acceleration – Clean carb jets and fuel petcock screen. Check fuel cap vent.
Loss of power – Replace fouled plugs. Clean air filter. Check valve lash and compression.
High oil consumption – Have compression and seals checked. Don’t overfill.
Backfires or sputters – Check carb float settings and fuel mixture. Clean jets/bowls.
Fortunately most common mini bike engine issues can be addressed or prevented with attentive maintenance before causing extensive damage.
Finding Replacement Coleman Mini Bike Engines
If your Coleman engine requires replacement, new and used options are readily available:
- Check Coleman Parts Direct – source for new OEM engines where available
- Shop popular mini bike retailers such as GoKartsUSA and BMI Karts
- Search eBay and Craigslist for used/refurbished takeout Coleman motors
- Find a local repair shop or individual selling refurbished small engines
- Consider lower cost aftermarket “clone” engines that replicate OEM specs
- Search for universal swap options like the Predator 212cc if engine model is no longer made
- Join forums such as ColemanTalk to buy engines from other owners parting bikes out
With some searching, you can find anything from new factory Coleman motors to low cost clones for any vintage mini bike. Measure mounting points and components to match properly.
Wrapping Up Coleman Mini Bike Engines
The engine truly makes the machine when it comes to Coleman mini bikes. Coleman has powered their iconic bikes using a range of 2-stroke and 4-stroke mills over the decades. From 50cc putt-putts to 212cc screamers, engine performance defines the model’s personality and capabilities. A huge part of mini biking is learning your engine – how to optimize it, maintain it, and enhance it. We hope this overview gives some perspective on the various Coleman powerplants. Match your riding style to the engine, keep on top of maintenance, and your Coleman mini bike will provide years of grins per gallon!
