Want A 15-25% Power Increase But Can’t Afford A Turbo?
The Drum Charger Could Be An Affordable And Easy Way To Increase Power!
Updated August 16, 2018
Simple, cheap, and efficient: introducing the “Drum Charger” by Alter Ego. It won’t compare to a turbo set up, but for smaller gains and a smaller price tag, this may be what your bike is missing…It’s not a budget turbo charger, but it a new approach for affordable forced induction that boasts up to a 25% increase in power, torque and efficiency at around the tenth of the price of a full turbo kit. Do we have your attention yet?
Forced induction is all over the place at the moment, but it’s still not a big player in the two-wheeled industry. Sure, the Kawasaki H2 has given us food for thought, and other manufacturers have promised more use of the technology in the future – that being said, the technology is still more or less out of reach for the everyday rider. Turbocharging, however, is pretty interesting – it increases the output of your engine. How? Using a turbine system, spinning compressors are able to create high pressures that allows riders to force feed their engines. Supercharging requires borrowing some power from the crank, but turbocharging capitalizes on exhaust gases.
Both methods are expensive – but Italian design house Alter Ego have come up with a nice compromise. Their new Drum Charger is similar to a turbocharger and makes the most of waste exhaust gases, but uses them in a different way. Instead of a series of complicated turbines and compressors, it uses a simple membrane.
In brief, the innards of the drum are based around an elastic membrane system. An offshoot pipe, from the main exhaust pipe, feeds in some exhaust gases on to one side of the membrane. On the other, you’ll find the usual air intake arrangement. Each time the engine pulses, the exhaust gas pipes into the drum system, pushing the membrane, which exerts enough force to increase the pressure in the air intake, firing a bigger payload of air into the combustion chamber. If that explanation wasn’t good enough (and it definitely was not) we recommend hitting the play button on the video below for the general idea.
You can see that the idea is more suited to single cylinder machines, since this forced induction system might not gel so well with infrequent exhaust pulses, and each unit works per cylinder, so you’d have to have a lot of bolt-on pieces for bigger bikes. You’re looking at a twin at the maximum. Either way, the gains are pretty impressive, with a boost to the tune of 4.35 psi for a single charger unit. Keep in mind that Kawasaki’s H2 belts out 20.5 psi, but for an incredibly high sum of money.
An Easy KTM RC390 Turbo Kit?
Alter Ego first unveiled their idea at this year’s EICMA bike show in Milan, with two bolt on Drum Charger units attached to a KTM RC390. Alter Ego said that with “little or no engine calibration” the KTM received an instant power and torque boost (to the tune of around 15%) across the rev range. They’ve also supplied us with a dyno chart for proof… It’s very impressive, but this type of technology will only appeal to smaller bikes. However, Alter Ego did say that the estimated price for a Drum Charger would be “about ten times lower than the cost of a turbo.” The kit would include the charger unit, a special exhaust pipe and airbox, and a fuel mapping configuration.
Despite its simplicity, Alter Ego are looking at marketing their Drum Charger idea to manufacturers rather than home builders, which can be sold as an OEM product designed specifically for certain models. However they end up selling their product, it’s an awesome idea. It’s so simple, we’re surprised it’s taken so long for someone to come up with it!