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Machine Elf
06-13-2011, 10:12 AM
Mass-produced cars have, for the most part, transitioned to electronic throttle control (http://en.wikipedia.org/wiki/Electronic_throttle_control). This helps with management of emissions and traction.

Motorcycles have been slower to follow suit. Harley Davidson introduced it on their touring models in '08, (http://www.americanrider.com/output.cfm?id=2019205) and BMW has it on their recently introduced S1000RR and K1600 GT(L).

How about the other big names, like Honda/Suzuki/Kawasaki/Ducati? Do any of them currently produce bikes equpped with ETC?

Pork Rind
06-13-2011, 10:36 AM
KTM has, at least on some of their bikes, a partial electronic throttle. The throttle is directly controlled by the user, but the ECU can take over at any point it needs to for emissions or rideability purposes. There are three switchable throttle maps that change the response rate. Rain, normal, and sport, or something to that effect.

KTM 690 models all have the same Keihin EFI system. This EFI system is different in a number of ways than on most - if not all - other bikes. It uses a 46mm single valve throttle body with two ECUs. One controling the fueling & ignition and the other controling the throttle valve through semi ride-by-wire. The ECUs interact with each other communicating over a CAN-BUS connection (CAN-H & CAN-L in the drawing). The two cables from the throttle grip hook up to the throttle valve but the ECU has the ability to 'take over' if needed. Closing the throttle valve is 'hard wired' for safety reasons. Under normal conditions the throttle valve will follow the commands from the rider 1:1. But if the throttle commands get outside the working parameters of the engine, the ECU will take over controlling the throttle valve in a way that the engine will keep performing optimal. For instance; wacking the throttle wide open in a split second at 2500 RPM in 5th gear will normally stall the engine. This is when the throttle ECU takes over and opens the throttle as quickly as the engine will allow without stalling. A neat and sophisticated system that works really well. The fact that you never feel the ECU taking over when riding a 690 kinda shows how good it works.

Machine Elf
06-13-2011, 11:52 AM
KTM has, at least on some of their bikes, a partial electronic throttle. The throttle is directly controlled by the user, but the ECU can take over at any point it needs to for emissions or rideability purposes. There are three switchable throttle maps that change the response rate. Rain, normal, and sport, or something to that effect.

I'm not clear on what "partial" means in this context, but it sounds like there is no mechanical connection between the rider's hand and the throttle body; in other words, it sounds like an ordinary ETC.

Placid Liver
06-15-2011, 07:05 AM
Yamaha's R1 has had this for the last few years' models I believe.
http://www.yamaha-motor.com/sport/products/modelfeatures/6/0/features.aspx

Hbns
06-15-2011, 10:08 AM
I think virtually all the major brand sport bikes (ZX, YZF, GSXR, CBR, etc) all have it now. As well as several touring models. It is pretty much a necessity for modern traction control system, that modulates throttle, brakes, ignition, and fuel to deliver virtually seamless execution on a motorcycle.

Motorcycle technology almost always lags automotive technology. Just not as much money available for development, and emission standards typically aren't as restrictive as for auto's.

Recent tightening of emissions standards, catalytic converter requirementts, and insurance company pressure for anti-lock braking and traction control are driving the trend toward full blown electronic engine management systems in more and more of todays motorcycles.

ETA Link to IIHS study (http://www.iihs.org/news/rss/pr033110.html)on motorcycle anti-lock brakes.

groman
06-15-2011, 10:46 AM
I'm not clear on what "partial" means in this context, but it sounds like there is no mechanical connection between the rider's hand and the throttle body; in other words, it sounds like an ordinary ETC.

Partial can refer to having two throttle bodies, one upstream one, mechanically controlled by the rider's hand, and one downstream one, that allows the ECU to reduce the air flow in to the engine. Being downstream it will not allow the ECU to ever open the throttle wider than the upstream one. However, this is just a WAG, since I do not know if this is done for motorcycles. I have seen this on cars for traction/stability control and such.