Newbie Question on rim brakes.
 

If you ride a bike with rim brakes long enough, will you eventually wear through the rim itself?

How many miles does that take?

I could see that being an advantage if you wanted a -forever- bike, just change pads and rotors.

Yes. Though it'd be more accurate to say that you'd wear the rims thin enough that they'd fail (tire pressure, bump/pothole).

Depends, but a lot.

Well, it's still the same bike if you change the wheels, innit?

Possibly. More people talk about it than actually wear the rim out. Far more people.

If you clean the rims and brake pads when it sounds like sandpaper when you brake, tens of thousands of miles.

I think the "forever" bike is a frame you can keep going, replacing other parts as they wear out. My favorite bike frame is nearing 50,000 miles on it (fork has 12,000 more, long story). The frame, fork, and brakes are the only original parts left. It's as close as I'm likely to get to a "forever bike." As soon as it stops raining, I'll take it out for (another) spin.

More interesting, perhaps, is the number of sets of pads one would go through before the rim would be considered worn out.

Ok. Thank you.

So if I’m coming up on 40. Full time job. Don’t commute on a bike. And only started getting back into bikes to ride with my kids- I’ll never wear out rims through braking.
If I want a disc brake bike for other reasons that’s a different subject.

Do disc pads last longer than rim brake pads?

You can always replace wheels. Or, if you can find rims with the same ERD, you can replace them forty years from now with a simple rim transfer and not even have to re-lace the wheel. Though rim brake compatible rims probably won’t be available by then.

Otto

Yes. No. Maybe. How long a pad lasts depends on how often you use them. That goes for disc pads or rim brake pads. People have posted here on the Forums that they have to adjust their brakes after each ride. I can’t remember the last time I replaced a pad (of any kind) because it wore out. I’ve never adjusted a disc pad for wear. It all depends on how you use your brakes. If you latch on the brakes at the top of a hill and drag them all the way to the bottom, you’ll wear the pad as well as the friction surface (disc rotor or rim) more quickly. If you pulse the brakes on a down hill...hit the brakes hard, slow down, get off the brakes, rinse and repeat...you won’t wear parts out as fast. You also won’t heat up rims and/or rotors as much either.

All the other comments are spot on. I just had to rip you on -forever bike.

Do you really want to be riding the same bike forever? Are you going to be happy foregoing all the improvements (arguable in some cases) that 50 years of cycling will bring?

Wheels will be an expendable item if you ride enough miles. I've never really ridden one bike enough to wear out the rims. I've got some that are close, but then I stopped riding that bike because newer bikes superseded it and were more fun to ride.


As for how many miles that might be, I don't know, the bike with the almost worn out rims is of unknown history. But it's a lot more miles than most will ride. If you wear the rim out, then be proud, post a pic and I'll clap for you. I'm sure a lot depends on how much you have to brake.

Anecdata here: Family fleet of bikes, used daily for commuting and around town plus weekend recreational rides. In my entire life I've replaced exactly one worn-out rim, and it was on a bike being used year-round in a particularly gritty area by a rider who was only using the rear brake and neglecting its adjustment.

Its not so much I want one bike forever as much as just looking at it from opposite perspectives.

I don’t ride bikes enough to wear a bike out.
Joined the forum to learn stuff because now my kids ride.

If they really get into riding, we all might upgrade from big box store bikes to LBS bikes and get fitted.

I pulled the springs out of my big box MTB fork and welded the stanchions together. Will probably do the same for my firstborn until we get different bikes.

It is possible, yes.

The failure is an extremely gnarly blow-out. The failure of the rim sidewall generally causes the rim's hook to separate from the rim base along a section. The tire finds itself no longer laterally contained by the rim, so it blows off. It sounds a bit like a gunshot.

Depends extremely heavily on the context. What conditions you're riding in, what rims, what pads, your maintenance habits. In most cases, tens of thousands of miles.

The big exception is if you're living somewhere where the regional gunk eats bicycles. Some people in the PNW burn through rims in just a few thousand miles if they're riding in wet conditions.

If rim wear is an issue for you, then yes, disc brakes can be nicer to deal with. Or, alternately, they can remove a reason that you weren't using nice rims.

I dont see a difference between changing a rim on a forever bike and changing pads and rotors on a forever bike.
Consumables are consumable.
Brake pads, rims, rotors, handlebar tape/grips, tires, bottom bracket, cables and housing- all of that is meant to be changed as it wears.

there’s really no such thing as a “forever bike” if you actually ride it. Almost everything bar the frame set is a “wear item” - some items simply wear slower than others. I’ve ridden the “same” bike for ~18 years/60,000 miles. However, I think only the frame, headset, seat post and one shifter are original - things wore out or I upgraded stuff as better versions became available. Wheels (rims) are one of those wear items. People who commute in bad weather will tell you they go through rims every couple of years. In contrast, I used the same wheelset for ~55k and there was still >1mm of brake track all round. I only replaced them because I wanted something a little blingier, but they’re still a perfectly good backup wheelset. If you ride in mainly decent weather and clean the rims/brake pads regularly, Al rims will last for decades

yeah, that would be a LOT of miles! By that time, your bigger problem would likely be spoke nipples (difficult to turn). You would have ridden so many miles by that time.......keep riding!

Blingy rims are much more expensive (both material and labor) to replace than blingy rotors.

If ridden in wet and dirty conditions (like a commuter bike) and cleaning of rims and brake pads is infrequent, you could possibly wear the sidewall of the rim thin enough that it cracks in a season or two. I have had one rim worn so far that the pressure from the tube split the side. Another wore down enough that it was starting to break and the spokes were losing tension and the rim would not stay true.

Disc brakes are the perfect solution for this, but regular cleaning of the braking surfaces is a decent preventative.

Didn’t think about that. But probably not as loud as a split ring on a tractor trailer giving way. “BOOM!”

https://www.bikeforums.net/bicycle-m...-out-rims.html

https://www.bikeforums.net/bicycle-m...-rim-wear.html

Just to be clear he was talking about complete failure. Not wearing out. I don't know if I've ever heard of anyone having such a failure, unless maybe a high dollar carbon which I'm not into yet.

When it's worn out, usually on many of the rims today, it'll look like a depression in the braking surface of the rim. Simply the outer wall of the rim getting thin and beginning to collapse. Some have wear indicators.

I'm talking about wearing out to the point of failure. The hook blows away because the sidewall between the hook and the rim base becomes too thin to withstand the tire pressure.

(Obviously you should replace a rim long before this happens.)

It usually happens with aluminum, since few people are cruel to high-dollar carbon road wheels.

I've been in the room when it's happened, but I also live in the Seattle area where we have rim-eating road grime. Even here it's a pretty rare occurrence.

The concavity isn't "collapse", it's present even without a tire on the rim. It's just the wear pattern, brake pads tend to eat away more at the middle of the brake track than the top and bottom.

One of my clubmates had his (aluminum MTB) rim explosively blow out on him a few weeks ago - a combination of thin brake track and a poorly-timed bunny hop. :roflmao2:

Theoretically, yes. In practice, seldom. The ones I have worn through have failed relatively slowly. I’ve even had strips of the rim fracture off and the result was just a pulse at the brake lever. Most of the time, however, the rim just splays out due to the pressure the tire puts on the rim.

I once had a steel rim on a Raleigh 3 speed bike split right down the middle of the spoke bed. The rim simply rusted through from the inside. The bike was ridden several winters on snowy salted roads. Not a spectacular failure, the rim split slowly and the wheel turned mushy. Was able it ride it most of the way back home

I think a far more common problem no one talks about is a rotor warping. You can true them yourself and rotors are cheap but it does happen.

Yeah, it happens, but it's an incredibly minor issue that's straightened out (ha ha) without much time or effort. The Shimano IceTech rotors, in particular, are super easy.