geometry: how your bike handles

The basic geometry of a bike’s chassis is vital to how it feels and performs. But sometimes it can seem like a bit of a black art. Here’s our guide to what it all means…

What do you look at when you first see the specs for a new bike? If you’re anything like me then that’s a bit of a daft question – it’s all about the brake horsepower and the dry weight, isn’t it? Then we’ll maybe enquire about how fancy the brake calipers and suspension are, writes Alan Dowds.

Finally, we’ll skim-read the electronic aids package – then all that remains is to see if it comes in colours to match Boothy’s special orange leathers. The question is, do you ever refer to the lower reaches of the chassis specification, though? The rake and trail figures, and the wheelbase? Those are the headline figures on a chassis layout, but there’s a host of other details which the engineers and test riders have been sweating over for years.


Fork offset, wheel sizes, swingarm length, engine mount position, rear ride height, chain run, weight bias – all have subtle effects on how a bike chassis will work… or not work.

You can read the rest of this article in the Summer issue of Fast Bikes, in the shops NOW!

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