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11

I'm going to assume you have a very good reason for not taking the other car out of the garage to give yourself more room... People replace either the front or rear brakes together because they are "on the same axle" and replacing one side doesn't make sense because both sides should wear at the same rate. Replacing one side could make the car pull to one ...


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 ...


8

Overheated rotors can show some tell-tale signs. Once the metal has been overheated, it can weaken or warp which are both bad things. Some signs: Bluing Cracks These "spider cracks", "heat cracks", or "heat checks" are only on the surface of the rotor, but are still bad.


8

What is a freely spinning wheel? Of course, you should be able to spin the wheel by hand, but beneath the brake, bearing and transmission can apply lots of drag. My rear wheels do about 1.5 to 2 turns, my front wheels not more than half a turn when I put them in rotation by hand. While it's the same for the front wheel of my mother's car, its rear wheels ...


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

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 ...


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 ...


6

To my mind, a wheel should spin freely when spun on the jack. A little noise is acceptable but if the wheel is clearly being slowed down excessively or is particularly hot after use, something is not right. As regards causes for brake drag, there do indeed include seized or sticking pistons but could also include sticky or corroded caliper slides (the ...


5

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 ...


5

The most common issue that makes a car shake when breaking is warped rotors. With warped rotors when you break the pad and caliper slide side to side causing the vibration. Depending on how badly they are warped the vibration may only be felt at high speed but the worse they are the lower the speed the vibration will be felt at. The best solution is to ...


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

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 ...


4

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 ...


4

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 ...


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

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

Provided that the other disc is still within acceptable tolerances with regards to width, you can replace a single disc. I personally prefer to replace discs as a pair on the basis that if one side is worn close to its useful life, the other is likely in a similar state. You could look at having the discs turned on a brake lathe as an alternative to ...


3

The previous poster have great examples of rotors in need of replacement but I worked as a mechanic for years and rotors have become so cheap for most vehicles the easiest thing to do is replace them as paying someone to resurface often costs more on labor than buying new rotors. The most common symptom is shaking in the steering wheel when braking from high ...


3

3 ways: Drive the vehicle and do both light braking from 25mph then hard braking from 55mph, if the brake pedal pulses up and down or the steering wheel shakes or vibrates, then you have at least one warped rotor. If stops are smooth and relatively noise free then go to #2 below. Pull the rotors and do a visual inspection, look for cracks (even small ones) ...


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

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 ...


2

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.


2

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 ...


2

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 ...


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 ...



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