Rotor advice

beefcake2

I have just ordered a set of these:

http://www.merlincycles.com/shimano-xt- ... 55284.html

I am riding a cube ltd pro (26 inch wheels). I currently have a 160mm rear rotor and a 180mm up front. I weigh 17.5 stone so am no lightweight and while upgrading my brakes from the original standard brakes I was wandering if I should increase the rotor sizes as well. I was thinking that a 203mm up front could be overkill but am not sure as I have never riden with one. Should I go 180mm front and back? Any advice would be great! My fork is a roxshox reba.

Thanks

Beefcake2

cooldad

180/160 is plenty.

beefcake2

Thanks for the reply! Would that be the case even at 17.5 stone?

cooldad

No idea how much stones weigh, this being the 21st century, but I am about 95kg and manage fine with 160mm both ends. And rubbishier brakes.
The XTs will stop you no problem.

poah

buy 203 mm if you want bigger rotors, no reason not to buy them - I've got F203/R160


95kg = 14st 13lb

cooldad

Massive rotors, especially with powerful brakes, give less modulation, so it's a trade off.

poah

cooldad wrote:

Massive rotors, especially with powerful brakes, give less modulation, so it's a trade off.

couldn't tell the difference in modulation between 160 & 203 TBH

The Rookie

Then you must be a Gorilla, as everyone 'normal' can!

13stone kitted and I ride 160mm both ends, never have a problem with lack of braking and can put it on the front wheel one fingered.

mcnultycop

I'm about 115kg (so 18 stone ish) and run 203mm up front on both bikes, and 180mm rear on the FS with a 160mm rear on the HT. This feels like the right amount of power (Magura MT2 on the FS, Deores on the HT).

I ran 160mm rotors on the front of the HT for ages, and whilst it was OK I just wanted a bit more. I'm sure a 180mm would be adequate, but I'll stick with the 203mm for now.

peter413

I'm about 105kg and run 140 rear, 160 front with Deore's on my Maxlight. Was running 160 rear, 203 front on the Marin with Deore's but now running a 180 on the front with the Saint and I could have with the Deore as well if I'm honest.

There are plenty of reasons not to go 203mm. Some forks won't take it, adds unnecessary weight, easier to hit, less modulation. The list goes on.

poah

The Rookie wrote:

Then you must be a Gorilla, as everyone 'normal' can!

13stone kitted and I ride 160mm both ends, never have a problem with lack of braking and can put it on the front wheel one fingered.

I could do the same but prefer the look of 203

rockmonkeysc

Even when I was 17 stone I found a 203 rotor too big on my xc bike. It was either on or off.
I only use a 203 rotor on my downhill bike where im getting much higher speeds and need to stop much quicker.
Strangely, even with 3 stone less I notice no difference with braking. I still use the same size discs.

poah

RockmonkeySC wrote:

Even when I was 17 stone I found a 203 rotor too big on my xc bike. It was either on or off.
I only use a 203 rotor on my downhill bike where im getting much higher speeds and need to stop much quicker.
Strangely, even with 3 stone less I notice no difference with braking. I still use the same size discs.

must have been an issue with your set up then - mine are not like that at all. modulation is not as good as the hope I used to have but its not on/off

rockmonkeysc

Nothing at all wrong with the set up. They are excellent at DH race speeds but at low speeds it's on or off.

poah

Zee's? mine are SLX so that would explain why the difference.

The Rookie

POAH wrote:

I could do the same but prefer the look of 203

I recognise the words, but not what you are saying!

poah

The Rookie wrote:

POAH wrote:

I could do the same but prefer the look of 203

I recognise the words, but not what you are saying!

that's because you are a moron

The Rookie

No, a moron would think that fitting 203mm discs for 'looks' was a good idea and I don't think that, ergo "I'm not the moron you are looking for!"

poah

The Rookie wrote:

No, a moron would think that fitting 203mm discs for 'looks' was a good idea and I don't think that, ergo "I'm not the moron you are looking for!"

I didn't fit mine for looks. sure they do look better than 160mm discs but they are more powerful which is why I did it. you need to stop reading between (and snorting) the lines

The Rookie

POAH wrote:

I could do the same but prefer the look of 203

That was hardly reading between the lines, and don't think we all share your habits please!