Directional brake rotor slots, does it matter?

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I'm looking at rotors for the CRV (actually don't even know if we really need them or not, but need pads) however TR has these $100 directional rotors for $50, but only for the one side. There are not ones we would normally look at, but the wife takes her brakes pretty seriously, and the CRV is not light...drums on the rear to boot. I don't think the direction really matters for light drivers and can get something good quality for 1/2 price. Kazera.

What do the guys think? Any other suggestions, we are thrifty.
http://www.tirerack.com/brakes/brakes.js...&perfCode=S
 
The photo of the rotor in the posted link, the rotor should rotate clockwise and should be mounted on the right side of the car. The holes farthest away from the center should "sweep" across the brake pads before the holes towards the center.

At least this is what I have read and have been told. Hmmmmm....next time I see an OEM fitment of drilled rotors I'll take note as to direction.
 
That's the thing, most X-D rotors are in a sweeping pattern, but are not specific. These are a good deal and all I care about is how well they last.
 
Hmm here is a suggestion. First, read BlueMax's posts on cross drilled rotors and why they are a waste of time. Second, since you are "thrifty" buy a decent set of regular, non drilled, non slotted rotors. Third, buy a good set of semi-metallic brake pads. Forget about the ceramic, high temp, racing, high performance type pads. OEM Honda pads are great. They last a long time and don't make noise. There are also other pads that will work, but avoid the cheap pads. Using good regular rotors and a good set of pads will make the brakes perform as well as they should be. Seriously, your CRV doesn't need slotted cross drilled rotors. It would be a waste of money. Buy regular rotors and invest the money in a good set of pads.
 
I've got slotted rotors on my 300M that are directional. Some guys in the 300M club have reversed the direction and didn't find any difference in performance, but it did result in an increase in noise. Slotted rotors are going to "moan" under heavy braking, and reversing the direction makes it worse.

Here is a pic of when I had mine put on. Note this disc is marked "R" for the right side. This shows the correct orientation for the slots. The end of the slot closest to the hub should contact the brake pad first, thus the sweeping action is to throw the gases outward from the center.

after.jpg
 
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Read acura tech's thread "waste of time and money" then re-read his above post. Take it seriously. He's telling you straight.

Bob

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Holes in car rotors are pointless and every hole is an extra potential place for the rotor to start cracking. The cheaper the rotor, the more likley you are to have problems.

crack.jpg


I'm not saying that holes in a rotor will make it crack, they just make it more likely to crack.

Done wrong, a lot more likely, done right, not much more likely to crack.
 
Slotted is better than drilled. You don't have the risk of fatigue cracks with slotted. I definitely would not get a rotor that is both drilled and slotted.
 
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Slotted is better than drilled. You don't have the risk of fatigue cracks with slotted. I definitely would not get a rotor that is both drilled and slotted.

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I agree. Drilling is more of a styling statement these days than anything else. Moderate slots do no harm and do some good.
 
Can anyone explain to me why slotted rotors are necessary on a grocery getter? Seriously!? What difference is it going to make other than costing more? Is your wife really that hard on the brakes? Sheesh. If I saw slotted rotors on a CRV I would be laughing. I really don't think the factory setup is deficient in any way whatsoever. But hey, there's one born every minute.
 
My mother's 1999 Honda CRV got only 25000 miles out of the factory front brakes. My mom does not flog vehicles. That car was cobbled together with stuff from a Honda parts bin to take advantage of the Cute Ute fad.

Some cars are prone to rotor warp, despite correct lug torque, and proper driving. My mom's 2005 Jeep Grand Cherokee has had brake pulsation since 25,000 miles, and there are about 38,000 miles on it now. Once the car needs brakes, I'm prescribing slotted disc brakes, and premium loaded calipers.
 
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Can anyone explain to me why slotted rotors are necessary on a grocery getter? Seriously!? What difference is it going to make other than costing more? Is your wife really that hard on the brakes? Sheesh. If I saw slotted rotors on a CRV I would be laughing. I really don't think the factory setup is deficient in any way whatsoever. But hey, there's one born every minute.

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Ninety-nine percent of the cases of "warped rotors" are actually cases of uneven pad filming on the rotor surface. Once rotors start to film, they just get progressively worse as the filmed area continues to build up pad material. Slotted rotors continually refresh the pad surface which almost eliminates the problem of filming. In the rain the slots also act just like tread grooves on your tires, i.e., they prevent a layer of water from building up on the rotor surface which can cause the pads to "hydroplane" and reduce braking power. Anyone who has driven in heavy rain and felt that initial hesitation in braking when you touched the brake pedal knows what I'm talking about. With slotted (or drilled) rotors the pads grip instantly in the wet just as if they were dry.
 
Quote:

Can anyone explain to me why slotted rotors are necessary on a grocery getter? Seriously!? What difference is it going to make other than costing more? Is your wife really that hard on the brakes? Sheesh. If I saw slotted rotors on a CRV I would be laughing. I really don't think the factory setup is deficient in any way whatsoever. But hey, there's one born every minute.

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AT, I bought my rotors/pads for a lot less than Honda wanted for theirs. So that is one reason why. I also wanted to try these out of curiosity due to what GMAN has posted about them.
 
Brembo blanks for $35 each is a no brainer here.

I don't care for slots or holes. Tried them all and blanks always works best.

You also have an excellent choice of pads at tirack. Brembo pads on sale at $43 is also a great price for a great pad. But, any of the ceramic or sports pads should work great.

A good yearly bleed, along with drum brake inspection and adjustment, would do plenty. Don't slam drums, they stop well enough!
 
Get plain rotors.
Less noise, pad wear, cracking, distortion, and are easier to remachine. Much less cost, too.
Those directional slots will push the pads up/down a bit, and can cause a knock.
 
Quote:

Can anyone explain to me why slotted rotors are necessary on a grocery getter? Seriously!? What difference is it going to make other than costing more? Is your wife really that hard on the brakes? Sheesh. If I saw slotted rotors on a CRV I would be laughing. I really don't think the factory setup is deficient in any way whatsoever. But hey, there's one born every minute.

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not necessary ..but sure look good on my Corvette
smile.gif

 
cross drilled seem to be the ones more likely to fracture in high heat situations.

Quote:

Here is a pic of when I had mine put on. Note this disc is marked "R" for the right side. This shows the correct orientation for the slots. The end of the slot closest to the hub should contact the brake pad first, thus the sweeping action is to throw the gases outward from the center.

Click to expand...


That is the opposite of what Bremo and stoptech suggest?
stoptech:


brembo slotted front on the RH side of my 2000 Outback:
brakerightfront1.jpg
 
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