Dynamic Stability Assessment of Different Wheel Sized Bicycles Based on Current Frame Design Practice with ISO Requirement for Bicycle Safety
The difficulties in riding small wheel bicycles and their lesser stability have been perceived for a long time. Although small wheel bicycles are designed using the similar approach and guidelines that have worked well for big wheel bicycles, the performance of the big wheelers and the smaller wheelers are markedly different. Since both the big wheelers and small wheelers have same fundamental geometry, most blame the small wheel for this discrepancy in the performance. This paper reviews existing guidelines for bicycle design, especially the front steering geometry for the bicycle, and provides a systematic and quantitative analysis of different wheel sized bicycles. A validated mathematical model has been used as a tool to assess the dynamic performance of the bicycles in term of their self-stability. The results obtained were found to corroborate the subjective perception of cyclists for small wheel bicycles. The current approach for small wheel bicycle design requires higher speed to be self-stable. However, it was found that increasing the headtube angle and selecting a proper trail could improve the dynamic performance of small wheel bicycles. A range of parameters for front steering geometry has been identified for small wheel bicycles that have comparable stability as big wheel bicycles. Interestingly, most of the identified geometries are found to be beyond the ISO recommended range and seem to counter the current approach of small wheel bicycle design. Therefore, it was successfully shown that the guidelines for big wheelers do not translate directly to small wheelers, but careful selection of the front geometry could make small wheel bicycles as stable as big wheel bicycles.
 Wilson D. G., Papadopoulos J. Bicycling science. MIT press; 2004.
 Proteus P. The Proteus framebuilding book: A guide for the novice bicycle framebuilder Proteus Design Inc. ; 1975.
 Kolin M. J., Denise M., la Rosa D. The Custom Bicycle. Rodale Press; 1979.
 Talbot R. P. Designing and Building Your Own Frameset: An Illustrated Guide for the Amateur Bicycle Builder. Manet Guild; 1984.
 Paterek T. The Paterek Manual for bicycle framebuilders. Framebuilders' Guild; 1985.
 BikeCad. BikeCad: Bicycle design software 2017. Available from: https://www.bikecad.ca/
 Hon D. T. Folding bicycles: A treatise. Dahon bicycle; 2016.
 Company M. B. Features (cited 2016 25 Jan). Available from: http://www.moultonbicycles.co.uk/features.html
 Forester J. Report On Stability Of The Da Hon Bicycle1989 cited. http://www.johnforester.com/index.html
 Cycles -- Safety requirements for bicycles -- Part 2: Requirements for city and trekking, young adult, mountain and racing bicycles, ISO 4210-2:2015
 Prince J. An investigation into bicycle performance and design: Auckland University of Technology; 2014.
 Whipple F. J. The stability of the motion of a bicycle. Quarterly Journal of Pure and Applied Mathematics. 1899;30(120):312-321.
 Timoshenko S. P., Young D. H. Advanced dynamics. McGraw-Hill Book Company, Inc.; 1948.
 Jones D. E. The stability of the bicycle. Physics today. 1970;23(4):34-40.
 Hand R. S. Comparisons and stability analysis of linearized equations of motion for a basic bicycle model. Cornell University; 1988.
 Sharp R. S. On the stability and control of the bicycle. Applied Mechanics Reviews. 2008;61(6):060803.
 Meijaard J. P., Papadopoulos J. M., Ruina A, Schwab A. L. Linearized dynamics equations for the balance and steer of a bicycle: a benchmark and review. Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences2007 p. 1955-1982. s
 Kooijman J., Schwab A., Meijaard J. Experimental validation of a model of an uncontrolled bicycle. Multibody System Dynamics. 2008;19(1-2):115-132.
 Moore J. K., Hubbard M., Kooijman J., Schwab A. A method for estimating physical properties of a combined bicycle and rider. ASME 2009 international design engineering technical conferences and computers and information in engineering conference: American Society of Mechanical Engineers; 2009. p. 2011-2020.