This could be a stupid question…….Why a bigger one at the front? What’s the theory?

When braking hard, 70pc of your weight will be put through the front brake.

Bigger front brake = more powerful, and less likely to overheat when using them a lot!

most braking occurs at the front bigger disc + larger circumference = more braking – ride downhill try and stop yourself with just a back brake now try with your front

It takes more power to slow the front wheel because all your weight is on the front when you brake hard giving you more traction, while the back easily locks up as it is unweighted. bigger disk = more leverage and therefore power.

Yep, that’s correct.

Cars, vans, motorbikes: They all have bigger more powerful brakes at the front for the very same reason. 🙂

Cheers all, makes perfect sense. Would I be right in thinking that by having a larger front disc and pulling on the levers equally the bike would have a more balanced and controlled stopping behaviour? A form of automatic modulation if you like?

Correct me if i am wrong but I think the larger disc would have a proportionally reduced modulation as the modulation would be over smaller range of resistance.