how do i know what maximum size rotor I can go?

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how do i know what maximum size rotor I can go?

Postby LoveB » Wed Dec 08, 2010 4:36 pm

I'm getting 203mm rotors from scotto on the board. I currently have 160mm on the bike and was told I can go bigger with the adapter kit. But question is how much bigger? I was told I cant go any bigger than 160 at the back. Could I safely go 203mm up front?
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by BNA » Wed Dec 08, 2010 4:47 pm

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Re: how do i know what maximum size rotor I can go?

Postby Nobody » Wed Dec 08, 2010 4:47 pm

Can't see why not, other than the lever becoming too sensitive which can limit effective modulation. Many manufacturers say don't go past 185mm with a quick release, but some people on these forums and myself believe a 160mm rotor will put more stress on the quick release. This is due to the leverage effect of the tyre on the quick release, with the brake pad as the pivot point. As the pivot (brake pad) moves further out, the leverage is less. Maximum braking power is limited to the traction of the tyre anyway.

The reason you wouldn't go more than 160mm on the back is you don't need the brake leverage or the heat dissipation.
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Re: how do i know what maximum size rotor I can go?

Postby LoveB » Wed Dec 08, 2010 7:14 pm

Shmanks. I cant go bigger on the rear cause the disk will hit I think. Anyway now I gotta find myself adaptors :D
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Re: how do i know what maximum size rotor I can go?

Postby scotto » Thu Dec 09, 2010 5:31 pm

Chck your fork manufacturer website
ie, SRAM says my SID team can cope with 185 max. not sure why, but who am I to argue !
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Re: how do i know what maximum size rotor I can go?

Postby LoveB » Thu Dec 09, 2010 8:57 pm

scotto wrote:Chck your fork manufacturer website
ie, SRAM says my SID team can cope with 185 max. not sure why, but who am I to argue !



RST site doesnt work for me :( I'll re check it.
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Re: how do i know what maximum size rotor I can go?

Postby Nobody » Thu Dec 09, 2010 10:43 pm

scotto wrote:Chck your fork manufacturer website
ie, SRAM says my SID team can cope with 185 max. not sure why, but who am I to argue !
Is it a bolt-up or Q/R?
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Re: how do i know what maximum size rotor I can go?

Postby LoveB » Fri Dec 10, 2010 12:56 am

I've got a QR on it.

image if it helps

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Re: how do i know what maximum size rotor I can go?

Postby Nobody » Fri Dec 10, 2010 9:06 am

Should be fine. Should be less trouble for the skewer than a 160. I've got a 185 and 160 and the 160 is more trouble with the skewer working loose. I believe the manufacturers have gone down this path as they are worried about legal problems if your skewer comes out of the dropouts. But as I said previously, logic points to smaller disc being a bigger problem with this. Regardless of what size or type of disc brake, checking your skewer for tightness occasionally is a good idea.

This is their direction:
http://www.sram.com/_media/techdocs/dis ... compat.pdf
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Re: how do i know what maximum size rotor I can go?

Postby scotto » Fri Dec 10, 2010 11:57 am

what about that cable mounting. should it go inside of the fork - much less to catch on there ?
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Re: how do i know what maximum size rotor I can go?

Postby Nobody » Fri Dec 10, 2010 12:16 pm

I've got mine up the back of the fork. However mine are rigid. It looks like manufacturers run them on the inside.
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Re: how do i know what maximum size rotor I can go?

Postby Bentnose » Sun Dec 19, 2010 6:53 pm

Just wondering how does the skewer work loose because you have a 160mm rotor over 185mm rotor. Rockshocks Reba have a maximum recommended 185mm.
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Re: how do i know what maximum size rotor I can go?

Postby Nobody » Mon Dec 20, 2010 8:04 am

From above:

Nobody wrote:Many manufacturers say don't go past 185mm with a quick release, but some people on these forums and myself believe a 160mm rotor will put more stress on the quick release. This is due to the leverage effect of the tyre on the quick release, with the brake pad as the pivot point. As the pivot (brake pad) moves further out, the leverage is less. Maximum braking power is limited to the traction of the tyre anyway.
The quick release works loose the same way as a bolt works loose from shaking.
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