Brake rotors 160mm vs 180mm

[MamboNumber5]

Hi guys, my mountain bike has the classic 160mm disc brake rotors on both wheels. I have noticed that many MTBs now have 180mm in front (even the cross country bikes). What's the deal with them and what are the advantages? If I do more aggressive biking in the future, should I also consider switching to 180mm in front and would I need to adjust the whole front brake set? Yes, there are some answers on google, but I want to check with all of you first.

Thanks, Marco

[JoJoJo]

(08-15-2019, 05:29 PM)MamboNumber5 Wrote:  Hi guys, my mountain bike has the classic 160mm disc brake rotors on both wheels. I have noticed that many MTBs now have 180mm in front (even the cross country bikes). What's the deal with them and what are the advantages? If I do more aggressive biking in the future, should I also consider switching to 180mm in front and would I need to adjust the whole front brake set? Yes, there are some answers on google, but I want to check with all of you first.

Thanks, Marco

180mm has more breaking power, cools down faster and doesn't heat as quickly but in theory should be a tiny bit heavier which has no effect on me at all -> I personally feel slight difference with breaking power on downhills and larger rotors feel quieter on heavy loads but not 100% sure about that

[CharleyFarley]

(08-15-2019, 05:29 PM)MamboNumber5 Wrote:  Hi guys, my mountain bike has the classic 160mm disc brake rotors on both wheels. I have noticed that many MTBs now have 180mm in front (even the cross country bikes). What's the deal with them and what are the advantages? If I do more aggressive biking in the future, should I also consider switching to 180mm in front and would I need to adjust the whole front brake set? Yes, there are some answers on google, but I want to check with all of you first.

Thanks, Marco

I have 180mm front, and 160mm back rotors on my Specialized Fatboy SE. Not having ridden a bike with 160mm front, I couldn't say what advantage the bigger disc has. I would imagine the bigger the disc, the more braking power it has, but it depends on your needs. If you decide to change the rotor, you'll need a caliper adapter. Your present caliper should be okay. I don't know if bigger rotors have bigger calipers and pads, so you'd have to take that into consideration. No point in a bigger disc if the caliper and pads is the weak point.

I'm not into aggressive riding but I did ride over a very long, high bridge, earlier this year. Going down the other side, the bike hit 28.6 mph and was still gaining speed. I decided to reign it in a bit but handled the front brake carefully. Taking a header over the bars at that speed would result in some serious road rash if not death.

[hviz]

I've heard that 180mm+ rotors are must have for bulkier / bigger / heavier cyclists. You need that extra braking power.