A Better Balanced Bike?
On a recent trip from the farmers' market with a heavy load of fruit in my bike basket I started to wonder if the placement of the load on the bike makes any difference in the efficiency of the work I do. Would it be easier for me to have baskets on the back where I would pull the load as opposed to on the front where I must push my load. Is it simply too small a system to make a difference?
We put this to Jos Darling, Mechanical Engineering, University of Bath:
That's a tricky one, really. The answer is pretty much however you want to do it. If you're looking at just the rolling resistance the way tires work is that the more weight on the tire the more rolling resistance. What I mean by rolling resistance is how difficult it is to push the wheel forward against the road. As long as you keep the pressure in the tires at a nice high value you'll find they roll very easily. Whether you put the weight on the front or on the back, given it's got to be shared by one or the other, it's not going to make that much odds. That's the simple answer. But of course, it's never quite that simple. If you look at the finer detail you've got more complicated things like aerodynamics. If you've got a basket on the front that's probably not going to help a whole lot. You might do better to put the luggage on the back where it's hidden behind the rider. The other thing that you might find is that if you've got all the weight over the front then the front gets a bit wobbly. So rather than cycling in a nice, straight line, you're going to be wiggling a bit and trying to balance the bike more carefully. In a way that's going to waste some of your energy like scrubbing off the speed if you're trying to go round the bend quickly.
In a sense you'd better try and share the weight between the front and the back. The answer is it's not going to make much difference at the end of the day. Unless Bunny is whizzing down hills at enormous hills at speed in Portland I suspect the aerodynamics aren't going to be a big issue. You needn't worry yourself about where you put the weight.