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LA CHÈVRE
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Discussion Starter · #1 ·
I read something about it a while ago but cannot find anything about it...

I have a pair of Hope 2-piece rotors (what Hope calls floating rotors) and they aren't dead straight. Whatever I do, there is always a part of the rotor (about 1/4 of the rotor) rubbing the pads. Can I straighten them like a regular rotor?

 

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Let's ride
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They are tricky to get straight if you can. Since they move side to side, you bend them to the side and the move instead of bend. With that, you don't know if you moved them or bent them. After some pushing here and there, i eventually gave up.

Good luck with yours though.
 

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They don't move from side to side but are fixed solid via the rivits,
the floating referred to is the expansion of outer disc relative to the inner spider,
so yes just straigten them like you would with any other rotor.
 

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silly person
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No, DO NOT USE A SHIFTER ON THE OUTER RING.

I've posted before about the best way to straighten these. If you use a truing tool on the outer steel surface you will not remove the warp, but may put a twist into that band. They are not rigidly attached by the rivets and can move back and forwards slightly (about 5mm)

To straighten one of these rotors, identify which rivets are closest to the warp and apply gentle pressure to the rivet and aluminium carrier. I'd just use your hand. They don't take much pressure to straighten as the aluminium is fairly malleable. The steel band will follow the new shape of the carrier.

If you want some fun, try truing them so they don't rub on Shimano 4pots. There's a certain lack of tolerance involved. I think there's around 0.1 - 0.2mm clearance between pads and rotor. It took me a good half hour to get it right, but they've been right ever since (approx 1000km)
 

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Use your hands like you would on any other rotor,
mine are solid on the rivits as are my mates, 5mm movement, noway thats massive and would rattle.
 

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silly person
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856er said:
Use your hands like you would on any other rotor,
mine are solid on the rivits as are my mates, 5mm movement, noway thats massive and would rattle.
Solid sideways, yes. Now lock your brake and rock backwards and forwards. It should move, though not much.
 

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Martin.mac.au said:
Solid sideways, yes. Now lock your brake and rock backwards and forwards. It should move, though not much.
Nope doesn't move nor does my mates,
if it did I'd be worried,potential wear point that would only get worse.
 

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LA CHÈVRE
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Discussion Starter · #10 ·
Martin.mac.au said:
No, DO NOT USE A SHIFTER ON THE OUTER RING.

I've posted before about the best way to straighten these. If you use a truing tool on the outer steel surface you will not remove the warp, but may put a twist into that band. They are not rigidly attached by the rivets and can move back and forwards slightly (about 5mm)

To straighten one of these rotors, identify which rivets are closest to the warp and apply gentle pressure to the rivet and aluminium carrier. I'd just use your hand. They don't take much pressure to straighten as the aluminium is fairly malleable. The steel band will follow the new shape of the carrier.

If you want some fun, try truing them so they don't rub on Shimano 4pots. There's a certain lack of tolerance involved. I think there's around 0.1 - 0.2mm clearance between pads and rotor. It took me a good half hour to get it right, but they've been right ever since (approx 1000km)
Well, I haven't tried the bike out but on the workstand, it's silent and rub free! Thanks Martin!
 

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silly person
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Martin.mac.au said:
Which model are they?
How new are they?

Ahh never mind
http://forums.mtbr.com/showthread.php?t=102908&highlight=floating+headset
Looks like there's different kinds of Hope Rotors. Either way the method I suggested should work fine.

Good to here it worked Dan. I'm glad I could help.
Mine,
200mm front 180mm rear,
supplied direct front the factory end of march 06.
They don't move but expand and contract with changes in various temperatures as does my mates set,
this can be heard by a tinging noise when cooling down,to be honest if mine moved (especially in direction of rotation) I'd send them back,don't know whats going on
but it doesn't sound right that one moves side to side and another moves a rotational
direction,may give the factory a call but from from my own experiance plus what I've read and from info on some product ads they should be solid.
like this http://www.rutlandcycling.com/ProductDetails/mcs/productID/440
 

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LA CHÈVRE
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Discussion Starter · #14 ·
For the records, mine certainly don't move sideways and neither can they move any other way without serious heat.

According to Hope: they are designed so that when overheating and getting cold again, the brake track can expand without warping since the spider shouldn't move much, providing a stable base to keep the rotor true. The rivets allow the the brake track to expend but not move side to side, thus, preventing warping. They normally can't be moved by hands though.
 

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silly person
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Mine don't move sideways either, and on closer inspection probably only move front and back by about 1-2mm or so, not the 5mm I said earlier. They only do it when you lock the brakes and rock the bike. I can't do it by hand. Of course, 1 - 2mm at the rotor is a lot more at the handlebars. That's where I got my 5mm from.
 

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Martin.mac.au said:
Mine don't move sideways either, and on closer inspection probably only move front and back by about 1-2mm or so, not the 5mm I said earlier. They only do it when you lock the brakes and rock the bike. I can't do it by hand. Of course, 1 - 2mm at the rotor is a lot more at the handlebars. That's where I got my 5mm from.
Hmmm IMHO thats wrong however as your feeling it at the handlebars are you sure its not just the pads moving (as they do) within the caliper,this would account for the movement your feeling ???? just an idea.
 

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silly person
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Some of it is the pads, but there's definitely a bit of movement in the rotor. I'm not worried about it as I've heard quite a few reports of it happening, and is in fact fairly likely with the design. I'd had a look for the previous thread where I talked about it but I can't find it.
 

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I've got 05 Mono Minis w/ floating rotors. No movement either way. You might want to give hope a call or shoot them an email and find out if movement is normal. I'd imagine it's not. My front rotor isn't true. I'll try to "true" it by pressing at the rivet, and not trying to bend the steel braking surface.
 

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To give an update. I tried straightening the rotor by pressing on the rivets/alum carrier. Worked great. So far, it's straight. We'll see in time if it stays that way. Thanks for the help.
 
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