Known for its straightforward design and versatility, the Hammerhead Twister 250 Go Kart has captured the hearts of enthusiasts and new riders, just like its 150-class version. Among the few reputable Chinese-made go-karts in the market, it would be interesting to learn more about the competencies of this four-wheeler.
The Hammerhead Twister 250 is a dune-perfect 4×4 that is second only to the smaller-displacement GTS™ 150. Featuring 4-point safety seatbelts, race-type seats, and Polaris technology, this wheeler has successfully changed consumer perception about Chinese-made off-road vehicles.
From its specifications to its praiseworthy qualities, this guide will cover details about the Hammerhead Twister 250 unknown to many off-roaders. Continue reading if you want to be in the know.
About Hammerhead 250
The Hammerhead Twister 250 Go Kart (or Twister 250) was released amid the GTS 150’s success in North America. But unlike its best-selling sibling, the Twister 250 was more a massive hit in Canada than the U.S. – partly because the manufacturer sold more Twister go-karts in the country. Both consumers and dealers were so impressed with the wheeler that it earned a reputation synonymous with the likes of Can-Am and Yamaha.
The vehicle offers impressive low-end torque, smooth suspension, and a 47-mph top-end speed compared to the competition. It has the same standard features as its namesake, namely – a 4-point safety harness, digital speedometer, and adjustable steering wheel, to name a few. Perhaps, one of its biggest differences is that it is a step up in size from the HH GTS 150. It may not be the quickest or fanciest vehicle in its category. But given its price point, you get more than your money’s worth for owning this go-kart.
Hammerhead 250 Specs & Features
Engine
Like the HH GTS 150 go-kart we reviewed just recently, the Hammerhead Twister 250 comes with a powerful 244-cm3 engine that does not take ethanol-containing fuel. A 30-mm carb handles air-fuel mixture and benefits from an 8.5-liter fuel tank capacity. Compared to its 150-cc sibling, the compression ratio went up to 10.0:1. And while it does not make the power output any different, the increased compression lends to the Hammerhead GTS 250 top speed of 47 mph. Should you need better top-end performance, major engine transformations would help improve the maximum speed by at least five (5) mph.
| Engine Type | 4-stroke |
| Cylinder Arrangement | Single-cylinder |
| Carburetion System | Carburetor, VEKS4 & CV30 x 1 |
| Engine Cooling | Liquid cooling |
| Engine Fuel | Unleaded gasoline w/ rating of RQ90 or REC90, containing no MTBE (Methyl Tertiary Butyl Ether), ethanol, or methanol in the fuel blend |
| Fuel Capacity | 8.5 L/2.25 US gal |
| Bore x Stroke Ratio | 2.83 x 2.36 in |
| Compression Ratio | 10.0:1 |
| Displacement | 244 cm³ / 14.9 in³ |
| Horsepower | 14 hp/14.3 PS (10.5 kW @ 7,000 RPM) |
| Top Speed | 46.6 mph (75 km/h – advertised) |
| Starter System | Electric |
| Lubrication | Force & splash |
| Engine Oil & Quantity | 30 fl oz (887 ml) of SAE 15W-40 engine oil |
Drivetrain
Along with changes to the engine configuration, the Hammerhead 250’s drive system changed from a chain drive to CV shafts, which worked better with the CVT-type transmission. Clutch assembly aside, everything else is the same as the 150-cc HH Twister. The vehicle did not offer selectable driveline modes but compensated for that by providing a good amount of torque.
| Clutch | CVT (Constant Variable Transmission) dry clutch & variator |
| Transfer, Transmission Type | Fully automatic w/ reverse |
| Steering | Rack & Pinion |
| Gearshift Pattern | F-N-R |
| Drive System | CV shafts & Belt (direct rear) |
Ignition
The Hammerhead 250 has an electronic CDI mated to an electric start system. Instead of a triple-phase alternator, a flywheel magneto serves as the vehicle’s charging system, while a YTX12-BS battery like an Antigravity ATX12-RS Lithium Motorsport Battery w/BMS & Re-Start Technology (view on Amazon) and 12V auxiliary outlet power up electronic accessories. In case of starting difficulties, an NGK CR7HSA spark plug would be a suitable replacement for the original as both have the same heat range.
| Ignition | CDI (Capacitor Discharge Ignition) |
| Ignition Timing | Non-adjustable |
| Idle Speed | 1,400 ± 100 RPM – neutral |
| Spark Plug | NGK DPRSEA-9, 0.6 – 0.7 mm (0.024 – 0.028 in) gap |
| Generator | Flywheel magneto |
| Fuse | 10 Amp (main) |
| Battery | 12V (10 Ah)/10 Hr, YTX12-BS format |
| Battery Dimensions (L x W x H) | 150 x 87 x 130 mm (6.00 x 3.44 x 5.12 in) |
Tires & Brakes
Dual hydraulic discs on all fours comprise the Hammerhead’s brake system and handle stopping duties. 20- and 22-inch tires are mounted on aluminum wheels, improving the wheel-and-tire assembly’s longevity and resistance to rust and corrosion.
| Wheel Composition | Polished aluminum |
| Front Tire, air pressure | Tubeless, AT20 x 7-8, 150 kPa (1.5 kgf/cm2, 21.3 psi) |
| Rear Tire, air pressure | Tubeless, AT22 x 10-10, 200 kPa (2.0 kgf/cm2, 28.4 psi) |
| Rim Size, Offset, Bolt Pattern (F/R) | 8×5.5, 3+2, 4/110 – front / 10×9, 5+4, 4/137 – rear |
| Tire Tread Limit | 3 mm (0.11811 in) |
| Front Brake Type | Hydraulic discs (left foot control) |
| Rear Brake Type |
Suspension
A couple of improvements from the HH GTS 150 helped in enhancing the go-kart’s overall suspension system. Firstly, the wheelbase grew longer by seven (7) inches. Secondly, ground clearance increased by almost three (3) inches. Not only did these changes make for a smoother ride when traversing bumpy or rock-laden surfaces, but they also resulted in better cornering and vehicle stability.
| Frame | Steel |
| Toe-out | 3 – 6 mm (0.11811 – 0.23622 in) |
| Wheelbase | 1,680 mm (66.1 in) |
| Ground Clearance | 215 mm (8.5 in) |
| Front Suspension Type, Travel | Independent dual A-arms |
| Rear Suspension Type, Travel | Fully independent rear suspension w/ oil-damped shocks |
Dimensions
The GTS 250’s overall dimensions are almost the same as the 150, except for the height, dry weight, and payload capacity. The side x side is 100-lb heavier and with 40 lbs more load capacity than its smaller-displacement sibling, enabling it to accommodate taller operators better than its counterparts. Perhaps, the only downside is that the vehicle is massive and would require a considerably sized property to drive around.
| Length | 2,210 mm (87 in) |
| Width | 1,346 mm (53.5 in) |
| Height | 1,438 mm (56.6 in) |
| Track (F/R) | 1,160 mm (45.7 in) / 1,085 mm (42.7 in) |
| Dry Weight | 280 Kg (617 lbs) |
Exterior
A brush guard, front and rear fenders, projector-style headlights, hinged doors, and canopy tops come standard with all models of the Hammerhead 250. Unlike the GTS 150, its body panels are not finished in two-tone paint – although they are available in various colors, including silver, blue, and red. The vehicle has an open-cab chassis, as do most dune buggies or go-karts. Individual, race-style seats can sit the driver and one passenger.
| Headlight | 12V 35/35 W x 2 |
| Brake/Taillight | 12V 21/5 W x 1 |
| Seatbelts | Dual 4-point harness |
Price of a Hammerhead 250
Pricing for a brand-new Hammerhead 250 Go Kart would fall between $3,299 and $3,999 for the standard models. Unlike the smaller-displacement GTS™, the 250 version does not have a Platinum or Limited-Edition trim. Its list pricing also does not include extraneous fees like freight, set up, tax, title, license, or dealer fees. Pre-owned units are for the Hammerhead 250 are scarce, mainly due to the greater popularity of the 150-cc go-kart with consumers. Online forums and other social media platforms will be better venues for scouting secondhand vehicles.
How to Conquer the Dunes: 7 Tips
While the Hammerhead Twister 250 is already fit for the dunes and trails, it would not hurt to give it performance upgrades to make it more fun to ride. That said, here are a few recommendations and known practices proven to bring out the beast in the four-wheeler:
1. Power-to-Weight Ratio
A good power-to-weight ratio is essential to the acceleration and overall performance of your quad. And apart from tech-savvy Hammerhead owners, mechanics and aftermarket parts dealers understand this more than anyone else. To go about it – you either take off unnecessary weight from your vehicle, replace original parts with lighter aftermarket options, or custom-machine portions of your go-kart.
2. Optimize the Carb
Optimizing the carb or increasing its size will help improve the air-fuel mixture for your 250-cc go-kart. Generally, dune buggy owners would increase the stock carb size by at least two (2) millimeters. More ambitious mods typically involve a 6-mm jump in carb size (or higher), plus the addition of other Hammerhead 250 parts.
3. Upgrade to 300-cc
Upgrading your Hammerhead Twister from a 244-cc to a 300-cc displacement will enable the dune buggy to generate more energy and transfer power to the driveshaft, ultimately delivering more power to the ground.
4. Supercharge
Supercharging/turbocharging does wonders to a four-wheeler’s performance and acceleration, let alone a go-kart like the Hammerhead Twister. These market options are based on either a forced induction system or your vehicle’s exhaust system. Between the two, turbochargers (view on Amazon) seem to be the more popular option due to the ease of installation and fewer parts needed to complete the setup.
5. Install NOS
One common practice among more mechanically advanced buggy drivers is installing a NOS kit in their Hammerhead 250. Doing so increases Oxygen in the engine’s combustion chamber, allowing it to burn more fuel and generate more power. Consequently, this results in better acceleration, making the go-kart more suitable for ripping through the sand and racing against other wheelers. Others take it a notch higher by getting a Nitrous Oxide System Universal EFI Kit (view on Amazon), which entails changing the go-kart’s fuel system to electronic fuel injection.
6. Install Lift Kits and Longer Shocks
Installing lift kits and longer shocks increase rear travel by at least two (2) inches. Depending on how much longer than stock the aftermarket shocks will be, lift kits sometimes require removing the pan-hard bars at the rear of your Twister 250. Not removing the said bars will cause the engine to touch the back of the seats or hit the fuel tank as the shocks try to reach their bump stops.
7. Reinforce Rear Section
Although not necessarily flimsy, veteran owners highly recommend reinforcing the rear section of the Hammerhead Twister, particularly the stock engine mounting frame. Doing so will improve the longevity and overall handling of the go-kart on technical trails and its frame’s resistance to deformity.
Given the stated benefits of these performance upgrades, Hammerhead owners would typically hold back not because of the difficulty in carrying out these mods but due to the costs associated with them. Some enthusiasts spend roughly $1,000 to $3,000 (sometimes even more) in personalizing their dune buggies. Another consideration that prevents them from going all out with modifications is the increased risk accompanying the changes. Most often, mods put the vehicle’s capabilities beyond its original design limitations – hence, greater risk for the rider.
While these drawbacks should not deter anyone from improving the look and feel of their four-wheelers, they should be taken into serious consideration – to ensure mods done on the go-kart are not detrimental to both the vehicle and the rider.
Is the Hammerhead GTS 250 Worth It?
Now that you know the specs, features, and performance upgrades compatible with the four-wheeler, let’s go over the benefits and pitfalls of owning a Hammerhead 250 Go Kart – and whether or not the vehicle’s characteristics match its price:
Pros:
- Overall, the Hammerhead GTS 250 offers more standard features compared to the competition.
- Its digital gauge kit is conveniently visible on the driver’s side and looks much better compared to the instrumentation found on the Hammerhead 250SS.
- The fuel tank has been made more durable, preventing leakage and potential rider hazard.
- Off-roaders love the simplistic, straightforward design of the four-wheeler.
- Average to medium-built riders will find its cabin provides ample legroom.
Cons:
- The side x side tends to have starter/ignition problems after long periods of storage or non-usage.
- Given the nature of its applications, the four-wheeler is strictly for riders at least 16 years of age or above. Additionally, passengers below 12 years old are not allowed.
- Accessing the oil tank may prove difficult for some owners due to its location underneath the rear rack.
- The Hammerhead 250’s power mill and radiator are not known for tolerating extremely cold climates very well.
- Owners find the stock CV carburetor a bit of an upset and difficult to service, ending up swapping it out for a 30-mm Mikuni that provides better acceleration and top-end speed.
When buying a secondhand Hammerhead, be sure to check on the status of the wiring, connectors, CDI box, and oil tank, for starters. Test for spark and see if the machine does turnover (or if there is no attempt to do so at all). If there is none, do a complete cleanup of the carburetor – including jets, passageways, and filters. Change the spark plug, too, while you’re at it.
A thorough carb clean should resolve most problems with starting the engine. Otherwise, you will need a service manual and probably an examination of the quad’s electrical components. In some cases, incorrect valve timing turns out to be the culprit behind starting difficulties. It would be an entirely different story for brand-new purchases, as issues with the vehicle generally come from the absence of a PDI or proper pre-delivery inspection.
About Polaris
Polaris Inc. is an American firm globally recognized for spawning the snowmobile industry and introducing groundbreaking innovations in the ATV/UTV industries. Following the success of the 1956 Sno Traveler, Polaris eventually ventured into motorcycles and off-road vehicle production. For the next few years after entering these industries, the company focused on expanding its product offering and market reach. As a result, Polaris has acquired several name brands like the Shanghai-based HH Investment Limited – the original maker of the Hammerhead 250 Go Kart – in the process.
Conclusion – Hammerhead 250 Review
As consumers grow more practical, purpose-built off-road machines are slowly but surely becoming a preferred choice among riders. Thanks to the Hammerhead lineup, many adventurers realize that not all quality products need a hefty price tag or an extremely popular name brand. Furthermore, a four-wheeler need not tons of embellishments to perform excellently on the road, especially when it matters. If you want a go-kart that can effortlessly rip through steep inclines and straightaways, just look in the direction of the Hammerhead Twister 250.
Kris is an avid off-roader and outdoor enthusiast who loves to brave the elements and take on challenging terrain. He also enjoys sharing his passion and knowledge with others so that they, too, can appreciate the ride.
About Kris