2024 JMC Motors TC 250

The addition of the latest technical innovations ensures the 2024 TC 250 remains on the top step in the competitive 250cc 2-stroke motocross class. Now featuring E-Start and Electronic Fuel Injection, starting is simplified while performance on track remains unrivalled thanks to the highly sophisticated EFI system that delivers the perfect air/fuel ratio for instant, controllable power at all times. Expertly assembled with premium components as standard, the TC 250 benefits from exceptional build quality, which guarantees both performance and reliability. On top, new graphics inspired by the brand's Swedish heritage create a striking new look, which is applied to all-new bodywork with advanced ergonomics.

FASTER AND WISER

• Engine: The TC 250 engine is at the pinnacle of 2-stroke performance and weighs just 52.6 lbs (23.9 kg). Complete with the latest technical innovations, the TC 250 comes with electronic fuel injection (EFI) which reduces running costs, removes the need for jetting changes, and improves reliability. The addition of E-Start adds to the simplicity of this popular model and guarantees fast starting in all situations.
• Cylinder: The new cylinder retains a 66.4 mm bore and with the introduction of EFI for 2023, the traditional powervalve is replaced with an electronic exhaust control system. This highly innovative technology manages the opening of the lateral exhaust ports before the main exhaust ports open to deliver strong, controllable power. The upper contour of the exhaust port features a machined finish for improved port timing and unrivalled performance.
• Crankshaft: The crankshaft is designed with weight reduction in mind to increase throttle response. The perfect balance of rotating masses is achieved by balancing the weights of the crankshaft flywheel, the rotor, and the counter balancer shaft.
• Crankcases: High-pressure die cast production processes allow for the crankcases to be manufactured with a thinner wall thickness to keep the overall weight to a minimum and to position the shaft arrangements perfectly for optimised mass centralisation. This clever design aids the overall balance and agility of the TC 250 while the symmetrical engine mounts further improve the chassis' flex characteristics.
• Counter balancer shaft: The TC 250 features an innovative laterally mounted counter balancer shaft. This shaft significantly reduces engine vibration, resulting in a smoother and more comfortable ride.
• DDS clutch: The damped diaphragm steel (DDS) clutch fitted to the TC 250 is unique as a single diaphragm steel pressure plate is utilised instead of traditional coil springs. Housed inside a CNC machined steel basket, the overall clutch design contributes to the compact engine layout and features a damping system for improved traction and durability.
• Gearbox: The TC 250 features a 5-speed gearbox manufactured exclusively by Pankl Racing Systems for the highest level of durability and ensures smooth and precise shifting. For 2023, a redesigned gear lever tip design offers improved leverage and prevents dirt build-up, even in the toughest conditions.

RIDE EASIER

• Polyamide-reinforced aluminium subframe: Made from 60% polyamide and 40% aluminium, the two-piece subframe ensures exceptional strength and durability at an overall weight of just 3.9 lbs (1.8 kg). The lower subframe spars and frame mounts are manufactured from cast aluminium for significantly improved reliability. The upper section of the subframe is made from injection-moulded polyamide to enable specific flex characteristics and ensure a lightweight construction.
• Chromium molybdenum frame: The proven chromium molybdenum steel frame is refined for 2023. A new shock mounting, which is no longer connected to the main tube, significantly improves the anti-squat behaviour of the chassis. With optimised wall thickness in high stress areas improving reliability, the frame continues to offer advanced geometries and flex characteristics aimed at providing unparalleled rider feedback, energy absorption, and exceptional straight-line stability. The frame is finished off in a premium metallic blue powder coating with redesigned standard frame protectors offering superior protection, durability, and grip in any condition. Additionally, the inclusion of forged brackets on the lower frame rails allows for easy installation of the skid plate, which is available as a technical accessory.
• Triple clamps: Working in unison with the frame design and suspension set-up, the CNC-machined triple clamps ensure precisely calculated geometry for increased stability. Handlebar flex can be customised with the handlebar clamp that offers two mounting options - rubber-damped for less vibration, or fixed for enhanced front-end feedback. The upper triple clamp is stiffer to ensure a smoother fork action and plays a vital role in the perfect alignment of the front wheel for superior handling.
• WP XACT front suspension: New shim stack settings improve the overall balance, cornering agility, and riding comfort on the TC 250 for 2024. The 48 mm WP XACT forks are designed as a closed cartridge system with a capsulated, adjustable air spring and pressurized oil chamber for smooth action and consistent damping. Oil and air bypasses reduce pressure peaks and in combination with a mid-valve damping system, together with a hydrostop that applies a progressive damping force in the last 40 mm of travel, the forks provide precise feedback to the rider. The settings are easily adjusted via the single air pressure pre-load valve, as well as through easy access click adjusters for compression and rebound. Additionally, the air pump needed to adjust the fork's air spring pressure is provided as standard.
• WP XACT shock absorber: The all-new WP XACT rear shock is 100 g lighter and 15 mm shorter than its predecessor yet the travel remains unchanged. Inside the shock is a Computational Fluid Dynamics (CFD) optimised main piston for improved initial comfort which provides strong hold-up in all conditions. Different sized holes in the shims allow them to open more easily which reduces the overall stress of the oil flow. Complete with low friction SKF seals and a revised linkage system, consistent damping, comfort, and traction are guaranteed with rebound and both high and low speed compression now adjustable by hand.
• Swingarm: The hollow die-cast aluminium swingarm is manufactured from a single piece of aluminium using an improved die-cast production process for optimal stiffness and a 190 g weight reduction over previous generations. In order to optimise and match the flex characteristics from the frame, a 22 mm rear axle is fitted. Additionally, the chain guard and chain slider have been designed for improved durability and are less prone to catching on external objects.

EFFORTLESS ERGONOMICS

• Functional bodywork: Clean, Swedish-inspired design and ergonomics are tailored to allow riders to perform at their best for extended periods of time. Adapted after countless hours of testing, the contact points and surfaces in the rider triangle have been repositioned for 2023 to improve comfort on the motorcycle. A new, flatter seat offers unrestricted movement with a high grip cover ensuring riders stay firmly in place under hard acceleration.
• Airbox: Designed with precisely positioned inlet ducts aimed at reducing drag and air flow deformation, the airbox ensures unrestricted airflow with maximum filter protection. The Twin Air filter is easily accessed without tools, by simply removing the left side panel for simple maintenance.
• Hydraulic clutch: The high-performance Brembo hydraulic clutch system guarantees even wear, near maintenance-free operation, and perfect action in every condition. With this hydraulic system, free play is constantly compensated so that the pressure point and function of the clutch remain identical in cold or hot conditions, as well as over time. Countless hours of race-focused testing have proven the exceptional reliability of the high-quality, Italian-made Brembo hydraulic systems.
• Hydraulic brakes: The highest level of quality is guaranteed as the class-leading Brembo brake callipers are made from single pieces of aluminium for exceptional strength at the lowest possible weight. Together with a 260 mm front and a 220 mm rear disc, which are designed to prevent mud build-up, superior stopping power and braking confidence is guaranteed in all conditions.
• ProTaper handlebar: Developed between Husqvarna Motorcycles and leading handlebar manufacturer, ProTaper, the exclusive bend offers superior comfort, class-leading strength, and fatigue resistance at the lowest possible weight.
• ODI grips: ODI lock-on grips feature an innovative, integrated throttle mechanism and are installed without using glue. The throttle assembly offers easy free-play adjustment with the option to fit alternative cams for a personalised throttle action.
• Footrests: The CFD-designed footrests are extra wide to ensure better control of the machine while at the same time are less susceptible to catching on deep ruts, take-offs when scrubbing, and trackside barriers. This is achieved by a narrower mounting design in the frame layout, which also helps reduce overall weight.

MASTER YOUR ART

• Wheels and tyres: Assembled with CNC-machined hubs, lightweight spokes, and strong, black-anodised alloy rims by D.I.D, the wheels of the TC 250 are then fitted with Dunlop Geomax MX33 Motocross tyres, which feature a proven block-within-a-block design for more progressive cornering and superior grip. For improved on-track agility, the 110/90-19 rear tyre and 80/100-21 front tyre ensures optimal handling on a variety of riding surfaces.
• Exhaust system: The header pipe on the TC 250 is designed using innovative 3D modelling. The result is a perfect shape designed to deliver optimum performance across the rev-range while also being very compact to ensure sufficient clearance through deep ruts.
• Cooling system: Manufactured from high-strength aluminium, the radiators are designed using computational fluid dynamics (CFD) to channel air through them in the most effective way. A large centre tube through the frame reduces pressure at this point in the system for a consistent coolant flow while an internal thermostat further enhances reliability.
• Fuel tank: A 1.9 gallon (7.2 litre) fuel tank integrates neatly with the ergonomic bodywork. The fuel pump design and location allows the tank to be emptied further, which is particularly beneficial for longer races. For improved durability, the external fuel line is specifically routed to make it less exposed and susceptible to damage.

TECHNOLOGICALLY ADVANCED

• EFI: The electronic fuel injection system on the TC 250 brings many benefits. The ECU from Vitesco constantly analyses the running condition of the engine and delivers the perfect air/fuel ratio at all times through the state-of-the-art 39 mm Keihin throttle body. EFI also introduces two different engine maps, which can easily be activated via the handlebar-mounted switch for a personalised riding experience. Map 1 is backlighted in white, while Map 2 is backlighted in green. Additionally, a redesigned reed valve system improves intake tract sealing and prevents excess fuel building up, which would lead to rich running of the engine in extreme up or downhill sections.
• E-Start: For guaranteed, easy starting in all conditions, the TC 250 features highly reliable electric start technology with the system removing the need for a kickstart completely. The 12.8V 2 Ah Lithium-Ion battery is positioned neatly under the seat and close to the centre of gravity for uncompromised handling. Stopping of the engine is achieved via the same handlebar-mounted switch for improved ease of use and a simplified operation.
• Map switch: The electronic fuel injection (EFI) on the TC 250 allows for the introduction of two engine maps that cater for riders of all abilities. Map 1 (white) is the standard option and delivers linear, predictable power, while Map 2 (green) is more aggressive with a quicker throttle response and a sharper, more explosive power output. By simply pressing a button on the handlebar-mounted Map Select Switch, riders can toggle between the two options and select their chosen map.
• EMS: The engine management system (EMS) is designed to be small, light, and fast at processing data. It incorporates a Rollover Sensor (ROS) that cuts the ignition and shuts off the engine in the event of a severe crash for an additional layer of safety.
• Hour meter: The hour meter comes with an integrated fuel level indicator, which is visible on the FI status LED, and warns the rider when the fuel level is getting too low.
• Start/stop switch: The combined engine start/stop switch is located on the right side of the handlebar for easy, thumb-operated use. Not only simplifying the starting and stopping of the engine, but the removal of an additional stop only button from the handlebar reduces the risk of potential damage or activation in the event of a fall.

ENGINE SPECIFICATIONS

• Transmission: 5-speed
• Battery capacity: 2 Ah
• Cooling: Liquid cooled
• Starter: Electric starter
• Stroke: 72 mm
• Bore: 66.4 mm
• Clutch: Wet, DDS multi-disc clutch, Brembo hydraulics
• Displacement: 249 cm³
• EMS: Vitesco Technologies EMS
• Design: 1-cylinder, 2-stroke engine

CHASSIS SPECIFICATIONS

• Weight (without fuel): 99.6 kg
• Tank capacity (approx.): 7.2 l
• Front brake disc diameter: 260 mm
• Rear brake disc diameter: 220 mm
• Front brake: Disc brake
• Rear brake: Disc brake
• Chain: 520, Non-sealed
• Frame design: Central double-cradle-type 25CrMo4 steel
• Front suspension: WP XACT-USD, Ø 48 mm
• Ground clearance: 346 mm
• Rear suspension: WP XACT Monoshock with linkage
• Seat height: 939 mm
• Steering head angle: 63.9 °
• Suspension travel (front): 305 mm
• Suspension travel (rear): 293 mm