OBD IS ON-board diagnostics. If you were looking to one avenue of motorcycle development that's come on in leaps and bounds these last few decades then this is it.
Forget radial brakes (although they are of course excellent). Forget dual compound tyres. Forget even the matter of screwing something like 200bhp out of a road-going litre-capacity motor. No, the leading technological advancement of this new century is electronic.
OBD development has been led by the ever-tightening emission regulations. And while those regs continue to cause problems for manufacturers - we're talking ugly matters like shitty jerky throttle response, eg, Yamaha FZ1, BMW K1200S - there has also been a fair gain in other dynamic performance areas. So we can be greener motorcyclists but also more controlled and faster motorcyclists.
Go back 30-odd years and the matter of fuel and spark was quite straightforward and almost entirely mechanical.
Fuel was fed via a carburettor or multiple carburettors. Spark came via a magneto-generator and contact breaker points.
In the 70s bikes almost entirely converted to electronic ignition. The Japs had it, then even the old Brit bikes were converted thanks to the like of Lucas 'Rita' and Boyer 'Bransden' aftermarket ignitions, which offered electronic control of advance and retard of the timing.
Fuel injection arrived at or around 1980 with bikes like Kawasaki's Z1000, but universal adoption would not arrive for at least two decades. Part of the slowness in adoption was the limited processing power
of early Electronic Control Units (ECU) that accompanied the fuel injection. Carburettors could then still give comparable, if not superior, performance and tune-ability.
Today's fuel injection is far more advanced. To comply with Euro 3, most today are of a closed-loop
variety (see right), which essentially is fuel injection controlled using data collected both upstream and downstream of the catalytic converter, so as to ensure emissions are the cleanest they can be at all times. The fuel mixture is monitored for richness or leanness, the emissions checked post cat and adjustments are made to achieve the optimal mixture (typically one part fuel to 14.7 parts air, known as the stoichiometric point). But the ECU will also be considering engine speed, gear ratio and, soon, with BMW, even rear wheel traction too.
Traction control is nothing new to the car industry, who'll often refer to it as 'torque based strategies', which rely on a break between the throttle wire you operate and that by which the computer then operates the throttle valves themselves to effect all manner of modifications to ensure wheels stay straight and true. Sounds like Yamaha's fly-by-wire Y-CCT doesn't it? That's unlikely to be a coincidence and so it's likely this kind of traction control being used in MotoGP, probably finely metered so the riders can spin the rear wheel just enough to aid steering, but not so much as to bring on a high-side.
Probably. And so it's quite likely after Y-CCT, like BMW, Yamaha road bikes will soon have traction control linked to their existing engine management systems.
The catalytic converter:
What does it do?
It converts harmful waste - gasses carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC) - into less harmful nitrogen, oxygen, carbon dioxide and water. It does this by passing the gasses through a ceramic and stainless steel honeycomb coated with aluminium, silicon and precious metals such as platinum, palladium and rhodium.
They are very effective. They have brought about a 94% reduction in CO and HC emitted by bikes between 1999 and 2006 and a 50% reduction in NOx (source: ACEM).
Unfortunately it can't help with carbon dioxide (which cats actually produce more of). The only way to reduce that is by improving fuel consumption - the less fuel burned, the less CO2s emitted.
What's closed-loop?
Closed loop refers to a fueling map that not only monitors what's going into the engine but what's coming out. Earlier fuel injection systems would be called open loop (curiously, is there such a thing?) because downstream of the exhaust valve there was no monitoring.
Closed loop systems typically work off oxygen sensors after the exhaust valve but before the cat,
and another monitors gasses after the cat. Dependant on the oxygen measured in the exhaust gasses
the ECU will either richen or weaken the fuel mixture.
