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10

The only way to know if a rotor needs to be replaced is measuring it with a micrometer and comparing that to the manufacturers specifications, so, no, we can't tell you if it needed to be replaced. However, since this was your first brake job I seriously doubt they needed to be replaced. Common practices is to "turn" rotors when doing a brake job. The ...


7

You cannot tell from just looking at them (in most cases) ... you have to measure the thickness of the rotor to see if they need replaced. Also, it's hard to tell from the picture how deep the wear is on the rotor. The grooves could be 1mm deep, or 5mm deep ... it's really hard to tell. It really comes down to how thick the rotors would be after machining. ...


6

I was looking at this from an automobile standpoint wondering What the heck is he talking about?? The vast majority of vehicle rotors and drums are made out of grey cast iron!, then went back and reaslized you are asking about motorcycles and ATVs. To that end: Why are OEM parts made of martensitic stainless steel (AISI 4XXX series)? The main reason ...


5

Grey cast iron possesses some traits which makes it less desirable than martensitic steel for brake disc applications: it is more brittle, which means it is easier to crack it has very low impact resistance, making it less durable under heavy braking it has less hardness (400 Brinell vs 700 Brinell), so it wears more quickly if left uncoated, it is more ...


4

What is passed off as a "warped rotor", and blamed on the user running through a puddle after heating the brakes, is a myth. The shimmy feeling that comes from brakes is usually due to uneven friction material build-up on the rotor. This transfer from pad to rotor is supposed to happen, indeed it makes the brakes work better, which is why brakes function ...


4

This sounds a lot like the rear brakes are dragging. Basically, that means the brakes are always just slightly on, which causes the brakes to heat, and rapid pad wear. Note that hydraulic brakes will fail if they get too hot, due to brake fade, so this can become a serious problem. Checking for brake drag is very easy. Put the transmission in neutral, and ...


4

Most likely you need a new caliper. The pistons will stick and drag slightly when they're in need of overhaul/replacement. If any of the wheels are hot after driving, that's a very likely problem. You may or may not smell the classic "brake smell". If they're only sticking slightly, you won't notice the drag while driving, you'll just see the extra pad ...


3

This is a great question, so let me help. First, I am the owner an auto repair center in New Hampshire and rusted brake rotors are almost an everyday occurrence here. If you live in an area that uses a lot of salt on the roads in the winter, like we do, then this information most likely pertains to you. 99% of the rotors that we have to replace are due to ...


3

Types Drilled - commonly seen on motorcycles, the holes assist in cooling, weight reduction and allows water to be moved from the braking surface Grooved/slotted - aids in cooling and cleaning (allows air and dust to move from the inside of the disk to the outside) Drilled and Grooved - as above Vented - allow air in between the braking surfaces to aid in ...


3

Different types of discs are designed to either improve the performance, or improve the heat dissipation (preventing 'brake fade' which can occur if they get too hot) Plain solid discs - these are the most basic, as fitted to ordinary cars, they just have a solid block of steel. Perfectly functional for the vast majority of users. Vented discs - these are ...


3

Squealing can be caused by a pattern of grooves in the rotor that make it look like an old vinyl record. The thickness of the rotor makes no difference on squealing, so even if there was plenty of meat left on the rotor it still needed servicing. Depending on how thick the rotors were you might have been able to machine them instead of replacing them - but ...


3

The huge size is not limited to carbon ceramic, that's just an attribute of most high performance cars' rotors. Carbon ceramic brakes are more expensive because the exotic compound does a much better job of dissipating heat than traditional steel rotors. Because they are able to dissipate heat faster, they do not get "soft" as quickly as other brakes. Soft ...


2

This is not usual There is a reason this happens. When you put new brake pads on your motorcycle you have to depress the pistons in the calipers to make room for all of the new brake pad material you have on a new brake pad. When you depress the pistons in the calipers the buildup of the brake bad dust gets into the seal a bit. When you apply the brakes ...


2

What is passed off as a "warped rotor", and blamed on the user running through a puddle after heating the brakes, is a myth. The shimmy feeling that comes from brakes is usually due to uneven friction material build-up on the rotor. This transfer from pad to rotor is supposed to happen, indeed it makes the brakes work better, which is why brakes function ...


2

I would bet the problem is not that the rotors are warped (this really doesn't happen all that often). The problem is probably that after hard braking and then a sudden stop without release for a period of time, there is a small buildup of brake friction material which has embedded itself upon the surface of the rotor. This gives you a pulsating feeling when ...


2

Yes, the front wheel should spin more freely than the rear, for as you note, there is less on it to drag. As Steve says, a non-flat rotor would result in oscillation or pulsing when braking, which should be pretty obvious on a bike. You can check it for flatness using a dial gauge (or run-out gauge). My suspects would be a sticking caliper, or a failing ...


2

I'm a retired mechanic, I used to work on private car's and some commercial vehicles. The principal of disc brakes is the same although details might differ between car and m/cycle. Don't even attempt any brake work unless you are competent and have the right tools. You mentioned the possibility of a distorted rotor. Can you feel anything untoward when ...


2

Exactly what @Movemorecommentslinktotop said in his comment ... if the rear rotors, there is a second braking surface inside the rotor "hat" which is for the e-brakes. If you haven't backed these shoes off or if you have the e-brake on, you'll never get these off. The front brakes may be rusted around the hub and are not releasing. They can become "space ...


2

Sorry, but the rotors are the problem. It would seem like the edges of the holes stick up a tiny bit. The rotor is a much harder material than the brake pads. These edges dig out grooves in the brake pads so it can't contact the rotor at other points in the rotation and provide braking force/rust removal. Zoomed in ASCII art: Pad ---- < ...


2

New brake pads should always be installed on smooth rotors. That includes either new rotors or having the old ones resurfaced. The rotors need measured. If there is enough meat on them to resurface, then do it. If they are too thin then get new ones.


2

The special tool you are requesting appears to be an allen drive. They can be procured online by doing a google search for "allen drive socket"


1

I had 237,000 miles on my 2001 Accord and never had to replace the rotors. Just before I traded my car in for a 2014 Accord, my mechanic (not Honda) said I still had one more brake job left in the rotors. (When I was taking my car into the dealer, they were saying I needed brakes about every 30,000 miles; this on a car that was driven 90% on the freeway. ...


1

I'd be tempted to skim them on a brake lathe (or have them skimmed on a brake lathe if you don't have access to one yourself) and fit a fresh set of pads.


1

I would give it about a 99.9% probability that they will not exchange front to back. I've never ran into a set where you could (not ruling out there might be some vehicle out there which you can). The main reason for this is they are designed differently. The front brakes do about 70-75% (depends on the manufacture) of the braking for the vehicle. Because of ...


1

Take the car somewhere else for another opinion, as it sounds like this particular KIA dealership is trying to pull a scam. Pads typically last 30,000-80,000 miles depending on driving style, pad type, etc. So, replacing the brakes every year is not typical, especially with limited driving. Surface rust can appear on the rotors if they sit for a while, but ...


1

Just to be clear there is a lot that could be wrong with this car. For starters when you took apart the front brakes and replaced the side pins and lubricated them did you check that the piston was able to be pushed back into the caliper? Have you tried bleeding the brakes? Could be that a hose or line is screwed up causing pressure to be applied even when ...


1

Turns out the culprit was ultimately the accident I had Christmas Eve. The C-Clip inside the differential holding the rear-passenger-side axle shaft broke during the accident and we hadn't known. This was what was causing the rotor to grind against the pads and caliper bracket. Thanks to all who helped trying to find the needle in the haystack. We were just ...


1

Was the wheel/hub spinning freely while the brakes were off? (to rule out other causes of noise) Are there any signs of things touching that shouldn't? (the stone-shield behind the brakes is a common culprit of this, as it can easily get bent slightly out of shape) When replacing them, were there any noticeable differences between the brakes/hub/etc on ...


1

Depends upon the type of vehicle . If you have a car where the brake assembly is independent of the wheels , you do not have an issue whatsoever. on the other hand if you have a motorbike which has the rotor(the disc) attached to the wheel , if you depress the brake , the pads will stick together preventing you from reinstalling the wheel back into the ...


1

Are you talking about just the wheel/tire, or are you suggesting removing any part of the braking system as well? If just the wheel/tire, there is no worry.



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