Jacobsroodt
Grey Hound
- Joined
- Jul 27, 2010
- Messages
- 5,492
- Reaction score
- 668
- Location
- Blouberg, Cape Town
- Bike
- KTM 890 Adventure R
About a year ago, the big thing in the motorcycle news was the tighter emission standards for 2017. There were a lot of speculations but nobody really knew to which degree it would affect our bikes.
It was clear that the petrol fueled engines would have to run even leaner than earlier, and motorcycle engines with virtually no flywheel weight would still have to meet the same requirements as the heavier car engines. So the motorcycle manufacturers would once again face a much bigger challenge than the car industry.
There is no doubt that the motorcycle manufacturers R&D departments have been working overtime, and that they are using every trick in the book to make the 2017 bikes run reasonably well.
The leaner mixture will make the engines run hotter, but most modern water-cooled engines can survive the new leaner requirements and have an acceptable operating lifespan with few or no mechanical changes.
A few engine types have been equipped with titanium exhaust valves, and we will most likely see more bikes being changed this way in the future. The exhaust valves are by far the components that are under the highest thermal stress, and they have a very hard time with the lean mixture.
There is no doubt that we will experience more damaged exhaust valves and valve seats on high mile motorcycles than we have seen before.
Top end power on the lean burn engines are more or less the same as on previous models – at least in the brochure (The customers will not be happy if a new bike has less power than the old model).
But the manufacturers have been remarkably quiet on the fact that the leaner mixture is reducing low-end power, torque and rideability.
Take a look at the chart below where power and torque curves are displayed for a 2016 and a 2017 BMW R1200GS. The mechanical setup on the two bikes is identical, so the difference in output is closely connected to the programming of the fuel Injection.
Bottom line is that compared to the older models, the 2017 motorcycle will:
- Have a higher combustion temperature and a higher degree of thermal stress
- Have reduced power and torque at low to medium RPM.
As mentioned earlier, a lot has been done on the bikes (especially on the electronic side) to minimize the negative effects of the lean air/fuel mixture. But despite all the technology, the only way to release the full potential of the engine is to add a bit more fuel.
Bottom line is that the new bikes need the BoosterPlug fuel injection optimization more than ever, and the feedback we have received from riders with 2017 motorcycle models with BoosterPlug fitted is possibly even better than usual.
It was clear that the petrol fueled engines would have to run even leaner than earlier, and motorcycle engines with virtually no flywheel weight would still have to meet the same requirements as the heavier car engines. So the motorcycle manufacturers would once again face a much bigger challenge than the car industry.
There is no doubt that the motorcycle manufacturers R&D departments have been working overtime, and that they are using every trick in the book to make the 2017 bikes run reasonably well.
The leaner mixture will make the engines run hotter, but most modern water-cooled engines can survive the new leaner requirements and have an acceptable operating lifespan with few or no mechanical changes.
A few engine types have been equipped with titanium exhaust valves, and we will most likely see more bikes being changed this way in the future. The exhaust valves are by far the components that are under the highest thermal stress, and they have a very hard time with the lean mixture.
There is no doubt that we will experience more damaged exhaust valves and valve seats on high mile motorcycles than we have seen before.
Top end power on the lean burn engines are more or less the same as on previous models – at least in the brochure (The customers will not be happy if a new bike has less power than the old model).
But the manufacturers have been remarkably quiet on the fact that the leaner mixture is reducing low-end power, torque and rideability.
Take a look at the chart below where power and torque curves are displayed for a 2016 and a 2017 BMW R1200GS. The mechanical setup on the two bikes is identical, so the difference in output is closely connected to the programming of the fuel Injection.
Bottom line is that compared to the older models, the 2017 motorcycle will:
- Have a higher combustion temperature and a higher degree of thermal stress
- Have reduced power and torque at low to medium RPM.
As mentioned earlier, a lot has been done on the bikes (especially on the electronic side) to minimize the negative effects of the lean air/fuel mixture. But despite all the technology, the only way to release the full potential of the engine is to add a bit more fuel.
Bottom line is that the new bikes need the BoosterPlug fuel injection optimization more than ever, and the feedback we have received from riders with 2017 motorcycle models with BoosterPlug fitted is possibly even better than usual.
