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Discussion Starter · #1 ·
hey guys

I have some tektro novelas on my bike and I have had 2 rotors within about 3 months.

is there a reason for this?
can I bend them back easily?
cheers, Dan
 

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WillWorkForTrail
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What size rotors? Are you warping both or just one? What sort of terrain are you riding? How much do you weigh? What kind of rotors? Presumably at least one of them was the stock one, what did you replace it with? Did it warp too, or has the other stock one now warped? Your post is pretty vague. I'm sure there's a reason the rotors are warping, but no good ideas why based on what you've told us so far.
 

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Discussion Starter · #4 ·
What size rotors? Are you warping both or just one? What sort of terrain are you riding? How much do you weigh? What kind of rotors? Presumably at least one of them was the stock one, what did you replace it with? Did it warp too, or has the other stock one now warped? Your post is pretty vague. I'm sure there's a reason the rotors are warping, but no good ideas why based on what you've told us so far.
the rotor that is warping is the rear rotor only, the first one was the stock tektro rotor (140mm) I then replaced it with an avid hs1 160mm rotor. I am 65 kgs (I'm 16 years old) I ride a mix of dust, mud and petty much every terrain. The avid and tektro are both warped, I don't mind too much I just want to know what it might be
sorry about my post not being very detailed
 

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Discussion Starter · #7 ·
What size is your front rotor? Do you use your front brakes as much or more than your rear? Braking should be something like 60%-80% done with the front brake, and the rest with the rear.[/QUO both the front and the rear are 160mm rotors and I use mainly the front so that is what is confusing me because I only use my rear brake when I have to
 

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WillWorkForTrail
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Assuming there is no problem with the rear caliper causing the disc to be twisted as it passes through (read: the brakes are properly adjusted so the rotor is "pushed" as little as possible when the brakes are applied) then what I'd do is get a 180 to go up front, then move your good 160 to the back, and see how things go from there. I suspect you may be needing to use the rear more than you think because of the smaller disc up front.
 

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Due to the way mechanical disk brakes work, rotors can warp easier. The reason for this is because there is one stationary pad (inner pad) and the moving pad (outer). So when applying the brake, the outer pad moves and pushes (flexes) the rotor on to the inner, stationary pad. When you release the brake lever, the whole process reverses.

On hydraulic brake systems, both pads move some what simultaneously and "mostly" grab the rotor on both sides at the same time. Therefore, the brake is not "flexing" the rotor.

That being said, I see two ways of minimizing this effect.

1) If the inner pad is adjusted to be close to the rotor, then the rotor would not have to be flexed (or even bent) much when applying the brake. The more you flex the rotor, the more you have a chance of the rotor being warped.

2) Use full stainless rotors instead of one of those fancy, lighter rotors. The full stainless ones will have more flex in them before they become "bent". The ones where the braking surface is somehow attached to a center carrier will not have as much flex (they are stiffer) and could tend to warp easier.

Anyway, I hope that helps a little. Other things to think about would be to make sure your rotors are straight to begin with. Then torque the rotor bolts when installing. This will insure even pressure on the rotor there by helping to mitigate some of the tendency to warp.

Oh, one last thought. With a mechanical disk set up, if your inner pad is dragging, after you've finished a long descent, and stopping for a long time, that one hot pad can be in touch with the rotor in just that one spot while the rest of the rotor cools nicely with the air. This can also lead to rotor warping.

Good luck.
 
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