Karting really does have classes for almost every age, size and ability from age 8 upwards, but sometimes the sheer number of options can be somewhat confusing. This pictorial display should help to explain. There are basically four different categories - Cadets, Juniors, Seniors and Gearbox for karts with gears. The non-gearbox ‘direct-drive’ karts only need to have a brake on the rear axle (although some top classes have a front brake too) whereas gearbox karts must have brakes operating on all four wheels. Most of the modern direct-drive karts have a centrifugal clutch so the engine can tick-over.
Other than the Junior 85cc category for 13-16 year olds, gearbox karts offer the highest powers and speeds. They can have either 2 pedals - brake and accelerator - like the direct drive classes, or 3 pedals, one of which is a foot clutch, like a car. Most 125’s use karts very similar to the direct drive karts except for the four wheel brakes. They have a hand clutch mounted next to the steering wheel, which is only used to move off from a standstill. At most circuits a standing start is used, as opposed to the rolling formation start that direct drive karts have.
Gearbox karts can also be used on the long motor racing circuits, although everyone should start on the short circuits which are typically 900 to 1300 metres in length.
The junior classes all have more powerful senior equivalents. The most popular senior class in the country is Rotax Max, but there are other options worth exploring at your local circuit. The once all-conquering TKM Extreme class is now only popular in certain areas, eg in the Midlands, and if you live in such an area it should be investigated. There are other TAG engines as well as Rotax, and TKM has a senior 4-stroke class. Once some experience has been gained there are further options for the premier championship classes. All use high-revving powerful 100cc 2-stroke racing engines. At the top of the tree is Formula A, the MSA British Championship class raced in Super One, then ICA (Intercontinental A), almost as powerful, then the slightly more economical 100 National. These classes will top out at 85mph.
ICC is the most popular gearbox class. Although a little more expensive than a direct drive class, they can be surprisingly economical to run. The 125cc water cooled engines have six gears, sequentially operated like a motorcycle using a gear-lever mounted next to the steering wheel. 0-60mph times are less than 4 seconds, top speed is 90mph on short circuit, 110 - 120mph on long circuit. The ABkC championship is promoted by the NKF.
This class uses an 85cc Honda or TM engine with 6 gears and is for 13-16 yrs. With its four wheel braking it offers the youngsters an experience close to a single seater race-car. It’s not raced at many clubs, but there are two national series.
The specification for Super ICC is identical to ICC except that the class weight is lower for this premier class. The ABkC championship is held in the BRDC Stars of Tomorrow series. Like ICC, the tuning of the reed valve engines is fairly restrictive, to prolong the life between rebuilds, and the tyres are very durable. The ICC and Super ICC are very popular in international racing. There is a good second-hand market for ICC.
This is the most powerful short-circuit class using 250cc single cylinder motocross 5-speed engines. The karts are often equipped with large full width nose cones and wings, especially when used on the long circuits. Top speeds are 100mph on short circuit, 140mph on long circuit. Twin cylinder Superkarts can reach 170mph though. The NKF holds the ABkC national championship.
A classic class using the Villiers 197cc engine or derivatives. Administered by the drivers themselves through the 210 Challenge group, contact is Kate Bateman on 01527 870834.
TKM Extreme is for 16 yrs upwards (although as in all the classes juniors already racing may move into the senior classes in the year of their 16th birthday). The engine is a115cc variant of the BT82. As with the juniors the chassis have to be registered, and new designs are only permitted every three years, to keep costs down. It’s a popular and economic class.
The senior equivalent of Junior Max, with a very powerful 125cc TAG engine. Although the maximum revs are limited electronically, they are nearly as quick as ICA, but much lower maintenance, and sealed to prevent unapproved tuning. Care needs to be taken if starting in this class. Like many classes there is a higher weight variant called Rotax 177 for the heavier driver.
A class for seniors only, using the previous generation of 100cc full race engines, but less costly because of the more durable tyres used. Like most senior classes, top speeds in excess of 80mph at certain circuits.
The premier 100cc direct drive class for seniors, for British, European and World Championship racing. Uses very grippy tyres and is expensive.
A premier championship class using reed-valve engines which can rev to 20,000rpm. Primarily raced in the Super One Series, and also as the entry point in senior European level racing. Not a class to start in.
New 125cc TAG engines are being introduced during 2007 to replace Formula A (becoming KF1), ICA (KF2), JICA (KF3). These will be raced in the major European and World events, and introduced to the UK for 2008, leaving 100 National as the ‘home’ for the ex F.A and ICA engines. At the same time, SICC and ICC are re-named KZ1 and KZ2.
