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Old 05-24-2019, 08:09 PM
Ken Robb Ken Robb is offline
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different size brake rotors

Help me understand how we can change the size rotors that we use on the same bike. Doesn't a different size rotor require moving the caliper? Are there mounting adapters for calipers to accommodate a change of rotor size?
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Old 05-24-2019, 08:24 PM
eddief eddief is offline
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yes

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Old 05-24-2019, 08:27 PM
jtakeda jtakeda is online now
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Quote:
Originally Posted by Ken Robb View Post
Help me understand how we can change the size rotors that we use on the same bike. Doesn't a different size rotor require moving the caliper? Are there mounting adapters for calipers to accommodate a change of rotor size?
Definite yes. Different size adapter
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Old 05-24-2019, 09:08 PM
Ken Robb Ken Robb is offline
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So showing even more of my ignorance wouldn't changing the size of the rotors change the leverage/sensitivity of braking i.e. bigger rotor= more leverage/braking force for a given pressure on the brake lever?
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Old 05-24-2019, 09:26 PM
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witcombusa witcombusa is offline
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Originally Posted by Ken Robb View Post
So showing even more of my ignorance wouldn't changing the size of the rotors change the leverage/sensitivity of braking i.e. bigger rotor= more leverage/braking force for a given pressure on the brake lever?
Yes. If you're bigger than the average cyclist or like one finger braking, larger rotors are your friend.
On a recent road bike went up one size on the front (from 160 to 180). For MTB use I went up one size on both front and rear discs. (from 160 to 180 rear, and from 180 to 203 front)
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Old 05-24-2019, 10:08 PM
dem dem is offline
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Samesy.. I went to a 180 front on my gravel bike, I really punish brakes. Pads I get 500 to 1000 miles out of, rotors 1500-2500.

With 500 miles the 180 seems much better, but time will tell.
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Old 05-24-2019, 10:32 PM
pbarry pbarry is offline
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Ken, are your brakes properly setup? Air in the system, improperly bedded pads and a few other things can cause less than optimal braking. If everything is good and you still want more braking power, then bigger rotors will make a difference.
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Old 05-24-2019, 10:52 PM
FriarQuade FriarQuade is offline
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It's kind of funny seeing these questions pop up all over again.

As you brake your weight shifts forward and the front wheel has more traction, thus can do significantly more of the work. Seeing how slowing down is always limited by traction in a wheeled vehicle. So it's pretty much standard to have bigger brakes in the front. You'll find this setup in pretty much every wheeled vehicle with brakes. Running the same sized rotors is the odd way to do it, but does have it's merits in some applications.
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Old 05-24-2019, 10:57 PM
PeregrineA1 PeregrineA1 is offline
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I run 180’s on my MTB’s and 160’s on my gravel bike. 200#’s of rider. I eat pads at a very close to equal rate and rotors equally close to equal every 1700-1900 miles. YMMV.


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  #10  
Old 05-25-2019, 08:14 AM
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wallymann wallymann is offline
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Originally Posted by FriarQuade View Post
...So it's pretty much standard to have bigger brakes in the front. You'll find this setup in pretty much every wheeled vehicle with brakes.
you'll find similar sized brakes F/R in harley-davidsons...not exactly a paragon of braking performance, but there it is. :-P
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Old 05-25-2019, 09:45 AM
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witcombusa witcombusa is offline
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you'll find similar sized brakes F/R in harley-davidsons...not exactly a paragon of braking performance, but there it is. :-P
You can count on the boys from Milwaukee to show you what best to avoid...
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Old 05-25-2019, 10:14 AM
Bentley Bentley is offline
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Mileage

I don’t recall going thru a set of rim brake pads in 2000mi, but I live in Flat Florida so that might explain it.
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Old 05-25-2019, 10:26 AM
Ken Robb Ken Robb is offline
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Originally Posted by pbarry View Post
Ken, are your brakes properly setup? Air in the system, improperly bedded pads and a few other things can cause less than optimal braking. If everything is good and you still want more braking power, then bigger rotors will make a difference.
I just wanted to learn about disc brakes for bicycles. All my bikes have rim brakes which work fine for my riding.
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  #14  
Old 05-25-2019, 12:28 PM
SoCalSteve SoCalSteve is offline
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Originally Posted by Ken Robb View Post
I just wanted to learn about disc brakes for bicycles. All my bikes have rim brakes which work fine for my riding.
I went through the same learning curve recently. It’s actually not all that complicated as flat mount frames-calipers have become the road bike standard and 140-160 rotors work seamlessly ( with an adaptor for 160 ).

I’ve been swapping out pads and rotors trying to find the perfect combination for ( close to ) silent braking. Been a fun adventure!

If anyone cares, the best combo I found is : Swisstop organic yellow pads and SRAM Centerline XR rotors. Not a cheap combination, but works very well.

Oh yeah, there are two styles of disc mounts. 6 bolt and centerlock. You can get adaptors to turn 6 bolt into centerlock. Centerlock is really easy to install-remove.

Good luck!
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