Carl Thunberg & Herman Wäpling presenterar sitt examensarbete

Examinator/handledare Chalmers: Prof Magnus Evertsson, IMS

Handledare: RGNT Motorcycles: MSc Henrik Hellström

Abstract
During the last few years, the market for electric motorcycles has expanded and
many new manufacturers have entered the market. The Swedish motorcycle producer RGNT Motorcycle is currently producing A1 motorcycles and would like to
investigate powertrain options for a more powerful electric motorcycle with comparable performance to a conventional internal combustion engine motorcycle.
This master’s thesis aims to provide RGNT with a technical concept study of an
electric motorcycle powertrain based on the principles of product development and
mechanical engineering.

The thesis work began with defining the problem, benchmarking competitors and
making a functional analysis to gain better knowledge and understanding of electric
motorcycle powertrains. The initial design targets and requirements were then
set together with engineers at RGNT Motorcycles and compiled into a requirement
specification sheet.

Calculations and simulations were made in order to define the specifications of the
powertrain based on the performance targets from the requirement specification
sheet. Overall dimensions and motorcycle parameters that were needed for evaluationswere compiled from existing motorcycles and relevant literature.

Different types of motors, primary- and final transmissions were combined to generatefeasible concepts. The concepts were evaluated using elimination and
matrices as well as packaging models in CAD. The number of concepts was gradually
reduced until three remained.

It was concluded that a PMSM axial flux motor with a belt drive would fit the motorcycle best. Initial mechanical design and CAD modelling of the final transmission and swingarm were made.

It was also found that the most suitable powertrain configuration is largely dependent
on the motor and inverter used and further work with souring these components
was recommended.