KTM Testing KERS On 125s

Unless you are an avid Formula 1 fan, the acronym KERS won't mean very much to you. The Kinetic Energy Recovery System, to give it its full title, is a system that stores energy generated by braking (either in the form of electrical charge, or in the form of a spinning flywheel), to be used to give a power boost at a later point in the race. The system was conceived by the FIA as a sop to the environmentalists who have been a thorn in F1's side for many years.

Fitting such a system to cars is an interesting proposition, and should not be too difficult, given the fact that it would take up relatively little space and weight on a four-wheeled vehicle. Motorcycles, it was generally felt, were less in need of such a system, as the weight and space penalty would far outweigh the benefits in terms of free energy. Add to this the relatively excellent fuel efficiency of motorcycles, and KERS would seem to be complete overkill on a motorcycle.

And yet from the testing done by the 125cc class at Valencia earlier this week comes some fascinating news, and an insight into why racing motorcycles might be the perfect platform for such a KERS system. The Spanish magazine SoloMoto is reporting that KTM has been testing an electrical KERS system on their 125cc race bike for the past few months, even giving the system an outing at the final Grand Prix of 2008 at Valencia, where Japanese rider Tommy Koyama shot off the line from 15th on the grid gaining 8 or 9 places, before nearly crashing and losing them all back again. Koyama went on to finish 7th, the KERS system apparently boosting his top speed down Valencia's long front straight.

Last week at Valencia, Marc Marquez tested the system further. Bartol explained to SoloMoto how the system worked: "It's a hybrid system. Under braking, the system charges capacitors (we don't call them batteries, because a battery can't charge quickly enough during deceleration), and discharges the energy along the next straight. It gives us about 2kW extra, although we only use it when the bike is in third, fourth, fifth or sixth gear."

At first, fitting a system like KERS to something the size and weight of a 125cc GP machine seems madness (the combined weight of the rider and bike must be at least 136kg). But when you consider that 2kW is probably close to a 5% power boost for a 125 GP bike, KERS suddenly makes a lot of sense. The 125 single cylinder two-stroke engines have been raced for 30+ years now, and are pretty well developed. Horsepower gains are prohibitively expensive using basic tuning technology, so a 5% boost is a big jump.

The only downside is weight. But with a minimum combined bike and rider weight, putting it on the bike belonging to Marc Marquez, the 16 year old rider who makes Dani Pedrosa look like a giant (when Marquez debuted in the Spanish championship in 2007, he had to add 20kgs of weight to get up to the minimum combined of 136kg) means that any weight penalty will be effectively neutralized.

It will be interesting to see how - and if - the FIM responds to this development.

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This is fantastic. I want details. I have to assume that the "generator/motor" (depending on whether it's being driven or driving) is coupled to the rear wheel, probably on the output sprocket somehow. Wouldn't make much sense to couple a generator to the front wheel (despite it being the place where the most energy is available during breaking) AND a motor on the rear wheel.

Whatever it is, it's super cool and is something that could and should find its way onto street bikes. While I'm sure the existing KTM system probably costs as much as an entire production motorcycle, in mass quantities, a dual purpose motor/generator, a few capacitors, the circuitry to control it all, and a few gears to get things spinning properly probably wouldn't be all that expensive.

I'm still EXTREMELY displeased with KTM for pulling the plug on the AMA Red Bull Rookies Cup, but hearing about this development moves them back up a notch or two in my book.

In the small displacement bike/scooter world the idea of hybrids are always greeted with much excitement. It may seem like overkill with vehicles that are already at the very efficient end of the fuel consumption spectrum. But it's the people that are most concerned about energy consumption that are enthusiastic about these new technologies. Maybe the extra boost in power will spread the love for hybrids.

...but this is still a form of propulsion that must be allowed and codified by the sanctioning body, and then carefully managed so as to prevent an "inappropriate" advantage from developing (call me a cynic).  Interesting for something like 125's, which can use some more speed, but then problematic for anything bigger.

Also, I think it wouldn't be necessary to put the generator on the front wheel (though it looks like that's what they did), since the rear wheel would be slowing a nearly identical number of revolutions, and the added drag on the rear wheel would be beneficial under braking (provided there's some sort of sensor protecting against lock-up unless triggered by the intent of the rider through the brake pedal).  What would be interesting is to see if there would be more gains from adding the drive motor to the front wheel instead of a complicated clutch system to the existing drivetrain.

Cue the talk of "expensive electronics"...