Basic drivetrain queries for the roadies...

Finally, Dave Yates, master framebuilder and audax enthusiast, has this to say about gearing (from his website):

"[FONT=Comic Sans MS]Work out what you think will be a low enough bottom gear and add one or two teeth to the sprocket ! When you are well into a long event the hills start getting steeper and gears you would not normally contemplate become very inviting. I consider a triple chainset a must although some still ride a double. A well thought out triple set up can actually weigh less than a double with big sprockets. The weight of the inside ring is negligible, the sprockets can be much smaller saving quite a big chunk of steel My own preference is for a 48-40-28 chainset with a 12-21 or 23 block I know its a bit high but you get the general idea."

Worth mentioning that (in person) he's very clear that your major expenditure should be on a really good set of wheels and tyres rather than the lightest/poshest groupset. I think it pains him a little to see people paying >£1000 for a gruppo and pairing it with a pair of cheapie Ksyriums or something.

FWIW, I have Campag Centaur compact on my Yates course bike and have found it works beautifully (though the shifters divide opinion a good deal).