Uneven front brake pad wear

[withiniswithout]

On my front hydraulic brakes, the inside pad closest to the hub is fairly thick, but on the other side I can't see any pad at all. Coming down a steep hill there was some screeching and the brakes weren't gripping and stopping well. Is this an install problem? Possibly something worn out or warped? The disc rotor has visible marks on it but no scoring or grooves. The front brakes are Shimano Deore 160MM Hydraulic. I get them serviced regularly at a professional shop.

UPDATE: The shop replaced the front and rear rotors and both sets of pads. Cost for labor and parts, €120. The rotors were quite worn and the thickness was below the suggested minimum. These were upgraded to Shimano SM-RT66; the stock rotors were the cheaper SM-RT56S. One thing I did not know: The 56S is softer metal and only resin pads should be used. The RT66 allows semi-metallic or resin pads. The 56S rotors lasted for 10,340 KM, with a lot of hard wear, and at least one set of semi-metallic pads that shouldn't have been used. I imagine the RT66 should last maybe 15,000 KM.

Update #2--After 5 months with the Shimano SM-RT66 rotors, I'm amazed. Braking is far better than it was. The pads are still OK after a full summer of riding. I suspect that semi-metallic pads were used on the old rotors and they didn't grip well and they wore out fairly quick.

Update #3--Still haven't replaced the brake pads. Haven't been riding as much due to the cold weather, but still these are lasting much longer. And for f's sake, enough already about the brake go-round. Get what works and forget about it. Learn as you go. Be open to surprises.

 

[fooferdoggie]

On my front hydraulic brake, the inside pad closest to the hub is fairly thick, but on the other side I can't see any pad at all. Coming down a steep hill there was some screeching and the brakes weren't gripping and stopping well. Is this an install problem? Possibly something worn out or warped? The disc has visible marks on it but no scoring or grooves. The front brakes are Shimano Deore 160MM Hydraulic. I get them serviced regularly at a professional shop.

The bike as 6300 miles on it, and lots of hard braking due to the many steep roads around here. Sometimes there's a 1500 to 2000 ft. elevation gain in a few miles.

they may not be centered well or a piston is stuck. but it would be time for new pads anyway.

 

[Jason Knight]

they may not be centered well or a piston is stuck. but it would be time for new pads anyway.

The cute part being that it seems the former can lead to the latter. More I learn about disc brakes on bikes, the sketchier the tech seems at this small scale.

 

[retiredNH]

The cute part being that it seems the former can lead to the latter. More I learn about disc brakes on bikes, the sketchier the tech seems at this small scale.

You prefer rim brakes? Geesh, even the worst disc brakes seem miles ahead of the rim brakes we had just a few years ago. I can't imagine rim brakes on an ebike, given the bike weight and greater speed potential. Yes, discs need adjustment and wear out. So do rim brakes, but even more frequently.

 

[fooferdoggie]

The cute part being that it seems the former can lead to the latter. More I learn about disc brakes on bikes, the sketchier the tech seems at this small scale.

nope they work great but cheap bakes are going to cause issues.

 

[TrevorB]

You prefer rim brakes? Geesh, even the worst disc brakes seem miles ahead of the rim brakes we had just a few years ago. I can't imagine rim brakes on an ebike, given the bike weight and greater speed potential. Yes, discs need adjustment and wear out. So do rim brakes, but even more frequently.

The Magura hydraulic rims are very good and on par with entry level disk pads. Both have pros and cons when comes to maintenance.

Back to problem at hand. Most likely piston on one of calibers is sticking. There are few videos on maintaining these on youtube. Remove pads, clean caliber with isopropyl alcohol/brake cleaner, I use cotton buds. Force each piston out by holding other in place with cable tie or tool while applying brakes. Clean around piston then lube with brake fluid. Cleanup with cloth don't use cleaner as it wash away fluid which you what for lubrication. Hopefully both pistons should move evenly now when brakes are applied. Push pistons home by fitting old pads and using screwdriver to lever apart, then fit new pads. Keep a set of olds pads for this, never use screwdriver directly onto pistons.

 

[EMGX]

You prefer rim brakes? Geesh, even the worst disc brakes seem miles ahead of the rim brakes we had just a few years ago. I can't imagine rim brakes on an ebike, given the bike weight and greater speed potential. Yes, discs need adjustment and wear out. So do rim brakes, but even more frequently.

That might be your experience, not mine. I have bikes with rim brakes and bikes with disc brakes, they both work fine. I live on a mountain with steep grades and coasting speeds up to low 40 mph even scrubbing off speed with brakes. I prefer rim brakes, they last longer, pads are inexpensive and easy to adjust and monitor, I'm on my third set of Shimano disc brake pads on one bike at $35 a pop although I've started to use generic pads which work just as well for $15 to $20 less. Hydraulic discs can be a hassle changing brake fluid or if you happen to get air in the system which happened to me out in the middle of nowhere, brakes dragged in the heat. To each his own.

 

[Stefan Mikes]

a piston is stuck

This.

I prefer rim brakes, they last longer

The rims do not. And I wouldn't apply rim brakes on expensive modern rims. Also, rim brakes fail during rainfall.

 

[EMGX]

This.


The rims do not. And I wouldn't apply rim brakes on expensive modern rims. Also, rim brakes fail during rainfall.

Discs can wear out, rims can wear out - I don't worry about it, I'd replace them if I ever need to and might be getting close on one set of rims. Regarding rain, I live in the rainy pacific NW, I generally avoid riding in the rain and am more cautious when I do but when I have I've had no problems with rim brakes slowing and stopping my bike. Loss of tire traction has been more of a concern than brakes.

 

[fooferdoggie]

it takes a lot to wear out a rotor I think it took about 8000 to 10000 miles to wear mine out.

 

[Stefan Mikes]

Discs can wear out, rims can wear out

Disks are inherently cheaper than the rims, and they wear very slowly. Rotor replacement is far easier and cheaper than rebuilding the wheels.

Regarding rain, I live in the rainy pacific NW, I generally avoid riding in the rain and am more cautious when I do but when I have I've had no problems with rim brakes slowing and stopping my bike.

Many of us ride all year long disregarding the weather. Never experienced any tyre traction issue but again I use good tyres. Necessary to mention I ride spiked tyres in the wintertime.

On one of my mountain rides, I had to cover a long and steep descent of totally cracked asphalt; it was impossible to be riding fast so I was using my disk brakes intensely. Down there in the valley we stopped. I touch the front rotor... to burn my fingers. I wonder how rim brakes would have fared there. (Good rotors are made to cool down as soon possible; it says something on that specific downhill ride!)

I often go for group rides with gravel cyclists. All of them use hydraulic disk brakes! Unlike roadies, gravel cyclists need to brake often, and it is often rain and mud.

 

[TrevorB]

Rims have lot more surface area and mass which means heat build up isn't issue. A 650 rim has 4 times surface area than 180mm disk so in theory 4 times life.

Some of Dutch style ebikes are still using hydraulic rim brakes as they are lot more forgiving in old style bike racks. These like bending disks. For most users of these bikes the rims will last life of bike.

 

[fooferdoggie]

Rims have lot more surface area and mass which means heat build up isn't issue. A 650 rim has 4 times surface area than 180mm disk so in theory 4 times life.

Some of Dutch style ebikes are still using hydraulic rim brakes as they are lot more forgiving in old style bike racks. These like bending disks. For most users of these bikes the rims will last life of bike.

of course heat buildup is an issue. its actually worse. tandems really had this use when decending with only rim brakes. but the problem is if you rim overheats your tire can blow off. I have heard of way to many people with this issue. people who had to stop and let their rims cool off on long decent.

 

[Jason Knight]

You prefer rim brakes?

Actually I prefer coaster brakes, but then I don't hot rod around like a maniac. I'm a comfort rider, only reason I got the Aventure was the fatties being better on snow. A promise they delivered on.

I find it comedy how my simple statement set off a firestorm of evangelism both for and against.

Though a LOT of what rim brake detractors are saying sounds like total BS unless the technology has changed for the worse in the decade plus I was away from bike tech. When a rubber rim brake is destroying your rims, what the hell rinky sleazy material are your rims made from? Much less heating up enough to blow tires off?

Again I'm a decade, maybe two behind on the 'tech. And there's always been a lot of bicycle tech I've found sketchy, dubious, and kind of based more on wishful thinking than engineering. See "derailleurs". Jumping a chain between cogs by applying shearing force and letting it skip through mid-air is about as jank a concept as you'll find. But it's cheap and it works. So maybe not THAT janky.

But to be fair, I have already gotten the zoom brakes on my Aventure to blow smoke coming down a hill... that I used to go down on my cruiser with coaster-brakes problem-free. I'd say it was the increased weight of the bike, but when I first started riding the cruiser I had another 100 pounds on me... I will say pad replacement -- rim or disc -- is a hell of a lot nicer than cracking open the rear hub.

 

[fooferdoggie]

Actually I prefer coaster brakes, but then I don't hot rod around like a maniac. I'm a comfort rider, only reason I got the Aventure was the fatties being better on snow. A promise they delivered on.

I find it comedy how my simple statement set off a firestorm of evangelism both for and against.

Though a LOT of what rim brake detractors are saying sounds like total BS unless the technology has changed for the worse in the decade plus I was away from bike tech. When a rubber rim brake is destroying your rims, what the hell rinky sleazy material are your rims made from? Much less heating up enough to blow tires off?

coaster brakes? I guess if you putter around its ok but it is not going to do crap if you have to do an emergency stop locking the rear up is the worst way to stop. there are plenty of stories of overheating rims. Plus aluminum is soft and grit on the rims will wear them out pretty well. this is why tandems used to come with drag brakes before disc brakes were the norm. all brakes can overheat I have overheated our tandem brights slightly on long steem decents try to keep the speed to 25mph.

Anybody had a tire blowout during a long descent? - Bike Forums

Touring - Anybody had a tire blowout during a long descent? - Raymond Bridge, author of the new Sierra Club's "Bike Touring: The Sierra Club Guide to Travel on Two Wheels" (2009) writes that a potential problem of rim brakes is that heating of the rims during long descents could cause a tire to...

www.bikeforums.net

Bicycle Touring: Forum: Wheels & Tires: "Heated rims from braking on big downhills", posted by Neil Gunton (neil) (admin) on Thu 23 Oct 2008 08:35 (US/Pacific)

Bicycle Touring: Forum: Wheels & Tires: "Heated rims from braking on big downhills", posted by Neil Gunton (neil) (admin) on Thu 23 Oct 2008 08:35 (US/Pacific)

www.crazyguyonabike.com

 

[EMGX]

Actually I prefer coaster brakes, but then I don't hot rod around like a maniac. I'm a comfort rider, only reason I got the Aventure was the fatties being better on snow. A promise they delivered on.

I find it comedy how my simple statement set off a firestorm of evangelism both for and against.

Though a LOT of what rim brake detractors are saying sounds like total BS unless the technology has changed for the worse in the decade plus I was away from bike tech. When a rubber rim brake is destroying your rims, what the hell rinky sleazy material are your rims made from? Much less heating up enough to blow tires off?

Again I'm a decade, maybe two behind on the 'tech. And there's always been a lot of bicycle tech I've found sketchy, dubious, and kind of based more on wishful thinking than engineering. See "derailleurs". Jumping a chain between cogs by applying shearing force and letting it skip through mid-air is about as jank a concept as you'll find. But it's cheap and it works. So maybe not THAT janky.

But to be fair, I have already gotten the zoom brakes on my Aventure to blow smoke coming down a hill... that I used to go down on my cruiser with coaster-brakes problem-free. I'd say it was the increased weight of the bike, but when I first started riding the cruiser I had another 100 pounds on me... I will say pad replacement -- rim or disc -- is a hell of a lot nicer than cracking open the rear hub.

Somewhat amazing to me is the price of the very simple material/tech bicycle components. $35 for one set of Shimano 105 compatible pads that have the combined friction surface of less than a postage stamp. I can buy a good quality axle set (4 pads) for my F350 that will stop a 8,000 pound vehicle from high speed, plus with few thousand pounds of cargo in the back, for that amount. 6 years ago I bought a new hand assembled 750cc Italian made motorcycle with ABS and traction control etc for just over $7,000 which is not much more than a higher end ebike with not a tiny fraction of the engineering, tech, materials and workmanship. More amazing to me is that anyone thinks that the cost is justified by the product.

 

[Jason Knight]

SMore amazing to me is that anyone thinks that the cost is justified by the product.

I often have the same feeling, but there's three things you need to factor in.

1) At this miniaturized scale there's a lot less margin for error in manufacturing. You also are trying to use a much smaller object to punch way above its weight. Sure each pad is the size of a forever stamp, but it has very little mass particularly in thickness to dissipate its own heat. It is also being used to brake on a smaller contact patch. Miniaturization -- part of where I find it a bit of ice-skating uphill-- comes at a cost.

2) Economies of scale. The lack of standardization, and the fact that manufacturers are going to sell a lot less bicycle brake pads than they do motorcycles or cars is going to drive up the price. The more of them you make, and the more uniform and universal they are, the lower the price.

3) Some people will spend crazy money, and greedy corporations know it. Look at sleazy dirtbags like Apple for proof enough of that. What with all the gullible ignorant fools they saddle up and take for a ride with their rinky overpriced half-assed products built entirely on "form over function", anti-consumer practices, and four plus decades of lies. If any other company pulled half the stunts crApple has the past 44 years, everyone involved would be doing jailtime. But through marketing, propaganda, and "status symbol" cult-like worship, they get away with it letting them charge a grand for something that probably shouldn't cost more than a quarter that.

A similar situation can be found in the "pay to win" mobile gaming space. Someplace I worked briefly and quit because it was too dishonest and borderline criminal. They don't actually care about mass appeal of their games. The entire "free to play" model isn't based on normal people, it's based on landing a half dozen "whales" who will drop tens of thousands of dollars into "winning". That's actually the industry term for the big spenders in games. "Whales".

We seem to see that same thing in bicycle tech now. People who will spend crazy money on a bicycle not for quality, but for the brand logo printed on it, the illusion of prestige. Bragging rights. Even when the product is indistinguishable from a XenSheHowSheWhaShe random word jumble brand from China. Worse there seems to be so much "tech for bragging rights" that keeps the hobby out of the hands of "normal people", and those so privileged seem unaware of their own status. The way some folks look down on those for whom a grand is a back-breaking investment reeks of country-club levels of dirtbaggery.

See some of the crazy stuff in terms of chains, chainwheels, and cogsets that are in reality no better than $20 or less Amazon specials. Unless you're a professional racer, you're just lighting money on fire.

 

[Robspace1]

I often have the same feeling, but there's three things you need to factor in.

1) At this miniaturized scale there's a lot less margin for error in manufacturing. You also are trying to use a much smaller object to punch way above its weight. Sure each pad is the size of a forever stamp, but it has very little mass particularly in thickness to dissipate its own heat. It is also being used to brake on a smaller contact patch. Miniaturization -- part of where I find it a bit of ice-skating uphill-- comes at a cost.

2) Economies of scale. The lack of standardization, and the fact that manufacturers are going to sell a lot less bicycle brake pads than they do motorcycles or cars is going to drive up the price. The more of them you make, and the more uniform and universal they are, the lower the price.

3) Some people will spend crazy money, and greedy corporations know it. Look at sleazy dirtbags like Apple for proof enough of that. What with all the gullible ignorant fools they saddle up and take for a ride with their rinky overpriced half-assed products built entirely on "form over function", anti-consumer practices, and four plus decades of lies. If any other company pulled half the stunts crApple has the past 44 years, everyone involved would be doing jailtime. But through marketing, propaganda, and "status symbol" cult-like worship, they get away with it letting them charge a grand for something that probably shouldn't cost more than a quarter that.

A similar situation can be found in the "pay to win" mobile gaming space. Someplace I worked briefly and quit because it was too dishonest and borderline criminal. They don't actually care about mass appeal of their games. The entire "free to play" model isn't based on normal people, it's based on landing a half dozen "whales" who will drop tens of thousands of dollars into "winning". That's actually the industry term for the big spenders in games. "Whales".

We seem to see that same thing in bicycle tech now. People who will spend crazy money on a bicycle not for quality, but for the brand logo printed on it, the illusion of prestige. Bragging rights. Even when the product is indistinguishable from a XenSheHowSheWhaShe random word jumble brand from China. Worse there seems to be so much "tech for bragging rights" that keeps the hobby out of the hands of "normal people", and those so privileged seem unaware of their own status. The way some folks look down on those for whom a grand is a back-breaking investment reeks of country-club levels of dirtbaggery.

See some of the crazy stuff in terms of chains, chainwheels, and cogsets that are in reality no better than $20 or less Amazon specials. Unless you're a professional racer, you're just lighting money on fire.

I agree 100%! There is so much bs built into ebike brands and what they will supposedly do better than others. Most is simply hype and like many other products, people overpay for the name then justify being ripped off by downplaying other, more affordable ebikes. I roll right by the super expensive, low watt, deluxe model, ebikes that are made to hide the battery and disguise themselves as analog road bikes. My converted cruiser is alot more comfortable and alot faster then 90% of the other ebikes out there. I ride with a bike club, with other ebikes at times. They fall behind on the hills. Many were sold underpowered ebikes. Pretty bike but no juice. My advice would be buy what you can afford and go with as much power as possible. Especially if you live in an area with mountains or steep streets. Why would anyone living in a city like Seattle or San Francisco buy an underpowered ebike? You need at least 750-1000 watts to tackle the hills out here. Any less and you may as well ride a super light analog bike. As for brakes, my experience is that brake pads are all about the same. I use resin for the peace and quiet. I go up and down steep hills alot. I don't ride in freezing cold or rain, and I clean the rotors with alcohol before every ride. Every so often I take out the pads, sand the shine off and put them back in. They stay quiet, work great and don't heat up. A little tlc goes a long way with disk brakes.

 

[TrevorB]

50-90nm 300w middrive motors with right gearing will climb any hill comfortably. While still giving experience of ride a bike not electric motorbike. Once you go over 750W may as well buy electric scooter or motorbike, safer faster and lot cheaper to operate than ebike.

 

[fooferdoggie]

50-90nm 300w middrive motors with right gearing will climb any hill comfortably. While still giving experience of ride a bike not electric motorbike. Once you go over 750W may as well buy electric scooter or motorbike, safer faster and lot cheaper to operate than ebike.

exactly. yes lower watts means you may have to work more but I am buying a ebike not a scooter. yes I had to work at this hill but his is extreme. if I was climbing such hills often I would have different gearing.