Designing a speed hump is not as simple as you might imagine. tinyurl.com/ye2a3go Read more

My wife gave me the idea for a totally new concept in snow tyres. She observed that polar bears and other arctic animals get a grip by having large but spaced out pads on their feet, interspersed with long fur.
So would the same idea work on wheels? Imagine the tyre consisting of two or three rows of pads, perhaps 2-3 inches across, and a sort of woolly mop all the way, strands perhaps 6" long. This could either be part of the tyre, or perhaps on a separate tough rubber strip which would be strapped onto the tyre just like a snow chain.

Has this ever been tried? Read more

Conducted a test this weekend on some very hard compacted snow with my 2003 Passat (normal tyres) and my brother's Audi A5 (winter tyres) to see whether there was actually a noticeable difference in stopping times.

Not that surprisingly, the A5 with winter tyres stopped in almost half the distance my Passat took. However, when watching I was puzzled by what I feel through the brake pedal and what I see at the wheel.

With ABS triggered, the brake pedal goes very firm and buzzes under your foot. The buzz is at least 30Hz. However, the wheel is actually locking, releasing, and locking again approximately 2x per second.

Can anyone explain the contradiction between what I feel and what I see? Read more

Chatting with an ex colleague recently, we got round to people we both worked with around thirty years ago. One fellow that came to mind was the firm's car expert, a bit of a dreamer who had come out with two memorable motoring "facts" (among others). One was to tell us how his mate had made a piston out of wood that worked perfectly (it was a very hard wood, we were told), and another was how he had fitted the back axle upside down on a Cortina and had one forward gear and four reverse.

Another ex workmate once informed the canteen table that one of the rear wheels drove the car forwards and the other drove in reverse. He had discovered this piece of engineering genius when he had the back raised on axle stands and watched the one wheel rotate in a different direction to the one he was turning by hand. What was even more amazing was that several other listeners nodded in aggreement while the rest of us burst out laughing. It's difficult to explain how a differential works so nobody bothered.

Anyone come across others with some weird motoring flights of fancy?
Read more

Here's a fine example of the Law of Unintended Consequences, as it applies to traffic lights in cold weather. It seems that the 'low energy' LED lights used in some newer installations don't dissipate enough heat to keep themselves clear of snow!

wattsupwiththat.com/2010/01/09/led-stoplights-fail.../

I suppose this might apply to vehicle lights, although I don't suppose it will be a real problem until LED headlights are invented... Read more