A 125cc Shifter Kart is a far cry from what most people think of when they hear the term “Go-Kart”.

A Shifter Kart is an extremely sophisticated racing machine, with a 125cc, water-cooled 2-stoke engine, producing upwards of 45 horsepower, with the power-to-weight ratio of a Ferrari, a Porsche Turbo Carrera, or other similar exotic and expensive sports and racing cars! 

This type of Kart has a six-speed sequential gearbox and four-wheel disc brakes, and the performance of these “pocket rockets” is astonishing, accelerating from 0 to 60 mph in 4 seconds, with the capability to reach top speeds in excess of 120 mph!

In addition to the rapid acceleration these Karts are capable of, the corning and braking performance is even more startling, and “neck stressing”, achieving lateral cornering forces of 2.5 g’s, with rapid de-acceleration under hard braking to match!

It has been said by many an expert, that driving these type of Karts are as close as you can get to driving a Formula One or Indy Car, in respect to the skills and reflexes needed to pilot these machines, due to the speed in which these Karts react to the drivers input.

In fact, many of the top professional race car drivers train in these types of Karts to stay sharp and in shape, as driving these Karts is extremely demanding physically, due to the high g-loads on put on the driver's body.

Quotes from well-know Racing Drivers and Automotive Journalists

From Autoweek, regarding Arie Luyendyk's (former Indy 500 winner) planned comeback to racing:

Instead of driving lots of miles before Indy, Luyendyk will concentrate on physical fitness, and that will include many laps on his Shifter Kart.  "It's probably the best exercise there is for drivers," he says.  "It's good for training and for your focus and for your reaction times, and it's probably as physical as any race car out there, especially on a bumpy track".

From Car and Driver Magazine, on Shifter Karts:

As Paul Tracy says, "It's the closest thing on four wheels to Indy-car racing, something I do in the off-season to keep my reflexes sharp".

From in invertview with Scott Speed (the only American in Formula 1) on SpeedChannel:

David Hobbs (former F1 driver, currently a commentator) discussing Scott's racing background..."Karting is absolutely unbelievably intense".

Scott Speed..."Driving a Shifter Kart around a go-kart track is very similar to driving a Formula 1 car around a track...it's just on a bigger scale".