Emission Reductions

“CO2 needs to significantly reduce for motorcycles to have credibility as low carbon transport” – LowCVP 2010

“CO2 emissions from PTWs are overall a very small share of total emissions. Given the fact of much lower CO2 emissions of PTWs per passenger, compared to passenger cars, the increase in trips conducted by PTWs will actually have a positive effect in the overall reduction of CO2 emissions from road transport.” taken from http://righttoride.eu/regulationdocuments/report_measures_motorcycle_emissions_en.pdf

What Level Of Emission Reduction Can We Expect?

Based on the Ultraboost project (SAE paper number 2014-01-1185) where the 60% downsizing resulted in a 23% improvement in tail pipe CO2 emissions the research suggests that our 70% reduction in swept volume should result in a 29% reduction in accordance with Ultraboost findings (pages 25 & 26 of above document) and research from “Future gasoline engine downsizing technologies” by McAllister & Buckley, before the additional benefits of hybridisation, etc.

Using the VFR800 as an example we get a downsizing factor of 62.5%, resulting in a new CO2 figure of 119.1 g/km. Hybridisation should reduce that to approximately 83.37 g/km. Transport For London suggest that an average motorcyclist rides 87 miles per week so this would represent a saving of over 546 Kg CO2 per year per motorcycle.

Running the same calculations for a one litre sports bike, using the average data for over 750cc bikes from the EU funded research based on a 29% improvement from downsizing and an approximate 30% improvement from hybridisation we can estimate the following savings:

Average urban emissions 750cc+: 171.2 g/km CO2
Average yearly mileage: 7238.4 kms (87 miles per week)
Average yearly CO2 emissions: 1.239 tons

Downsizing Yearly Saving (per motorcycle): 171.2 * 7238.4 * 29% = 359.37 Kg CO2
Hybridisation Yearly Saving (per motorcycle): 171.2 * 7238.4 * 30% = 371.76 Kg CO2

Of course, it is the larger capacity motorcycles that tend to do the highest mileage and, even more importantly, pollute the most in the urban cycle where the pollution has the highest impact. It is also the urban cycle where the hybridisation could see the highest electric only use, increasing the impact of the emission reductions where it matters most.

Overall Yearly Savings (per motorcycle): 171.2 * 7238.4 * 71% * 70% =  615.88 Kg CO2
1.239 tons CO2 -> 0.615 tons = Saving of 0.624 tons (49.7%)

To put that in to perspective: 171.2 g/km CO2 * 71% * 70% = 85.09 g/km CO2

Using the ECE calculations for hybrid vehicles, based on the electric only range, would result in an official CO2 output of 42.5 g/km (25 km electric only range), 28.29 g/km (50 km electric only range) & 16.97 g/km (100 km electric only range).

For more information on the ECE calculations please see paragraph 3.2.3.2.1 of the following document:

https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/updates/R101r3e.pdf