Bike prices..... WTF?

tomjasz said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

You are not taking into account the really crappy discs on so many bikes. BTW I have 26" discs.
Of course crappy stuff is gonna be crappy. But it does not cost that much to put some good stoppers on your bike. And it is money well spent!
 
wturber said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

For some applications, probably so. Long downhills on a tandem would be one. But in general, hardly. Quite frankly, I wish I had rim brakes on my e-bike. The squealing of the discs is driving me crazy. And sure, it is a solvable problem (that will cost me $$). But it is a problem I never had with rim brakes. And what I really should do is reconfigure so I can run regen/e-brakes. Horses for courses folks.

Jeepers, I don’t see how this can even be debated. In general, if the goal is to stop quickly, then disc brakes are absolutely superior. If your pads are squealing, try different pads. Rim brakes are famous for squealing, and must be “toed in” to prevent that honking racket that v-brakes are known for. Oh, and by properly toeing then in, you lose pad contact and stopping power.

Don’t get me wrong, I have bikes with old school cantilever brakes, v-brakes, caliper brakes, and a brakeless fixed gear. I’m not getting rid of those bikes, they stop fine and I love them all. But for Pete’s sake I can’t believe that anyone is still claiming that when it comes to effective stopping power, rim brakes are just as good (even better!!) than disc brakes.

The ONLY reasons to run rim brakes on an ebike are compatibly with your existing parts, or cost. And I do not understand the desire to save money on the most important safety component, for a bike that is way heavier and faster than it was designed to be.

If you want to consistently and reliably stop as quickly as possible, then it’s pretty simple...
 
tomjasz said:
My Reynolds 531 frame, Campagnolo equipped, pretty much the state of the art, is $2,787.33 in 2018.
Everyone I knew went nuts or thought I was for buying a $450 bike! I bought a second one because none of my dates had decent bikes.

I do not miss sew up tires!

Would love to see a pic of that one!
 
Chalo said:
neptronix said:
But yeah... walk into a bike store and you're gonna pay the 'westerner tax' usually :lol:

It's true-- when you go to a local bike shop, you're going to deal with employees who are from that area, and have to be paid enough to live where they live. This isn't the case when you get a box drop-shipped directly from a Chinese shipping container. The catch is, if you don't pay a local guy to do what he does, it might not get done at all. You can do your own work on your bike, but only to the extent that you understand what work you need and how to do it correctly.

That's where a frugal DIYer such as myself falls into a price hole.

I just bought a minivelo from a US company that resells a china made bike that's actually a pretty high quality piece. He put a ~50 dollar markup on it, vs the source. I see identically equipped bikes.. maybe made in China.. maybe not.. for about 5 times the price everywhere else. Then i look at Japanese made minivelos and they're half the price of what i'd pay here, but i can't get them shipped out, so..

Companies like to charge what the market will bear. I call that the 'westerner tax'. Things cost more because most westerners are either more willing, or more able to spend more. Markups can get into the 80% range on some of these things.

What's really shocking is the price per unit to get a bike made in Taiwan by a big company versus what you pay in the showroom.
$500 to make, $2000 to buy once it gets to you. Maybe the guy in Taiwan can get it for $900.
 
81forest said:
wturber said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

For some applications, probably so. Long downhills on a tandem would be one. But in general, hardly. Quite frankly, I wish I had rim brakes on my e-bike. The squealing of the discs is driving me crazy. And sure, it is a solvable problem (that will cost me $$). But it is a problem I never had with rim brakes. And what I really should do is reconfigure so I can run regen/e-brakes. Horses for courses folks.

Jeepers, I don’t see how this can even be debated.
When you say, "Way, way better" you open up lots of room for debate.

81forest said:
In general, if the goal is to stop quickly, then disc brakes are absolutely superior.
"Absolutely superior" That's an interesting description. Semantically we could say it is no different in meaning than just "better." But I guess "absolutely superior" sounds better than ... er I mean ... sounds absolutely superior to "better."

81forest said:
If your pads are squealing, try different pads.
Like I said, I know something needs to be changed and that they can be made to be quiet ... somehow. But in decades of riding I've never experienced this kind of persistent noise from brakes. Ever. That said, I've only had two bikes with cantilever brakes and I really didn't ride those particular bikes all that much. So maybe cantilever brakes are prone to noise too.

Anyway ... back to my main point. I'm a bit tired of the hype. Bicycles are fundamentally limited in stopping power by their relatively high centers of gravity. They are then further limited by the skill of the rider applying the brakes and the limited size of their tire contact patches.

When it comes right down to it, standard bicycles are fundamentally pretty flawed when it comes to braking. Apply your brakes poorly and you fly over the handlebars or skid a tire and stop really poorly, or crash if the tire you skidded was the front one on a loose surface. IMO, the trick with bicycling in general is to simply avoid situations where you must stop super quickly (panic) to begin with ... because that's not a strong point for bicycles. They don't have full-slam-on-anti-skid brakes. (Though maybe they should?!?) And for this reason I see no reason to hype up or get very excited about the issue much either way. Other issues are typically far more significant than whether your brake design happens to be rim or disc. In most riding environments/situations (not all), I don't think it really matters that much if you've already taken care of the really important things such as knowing how to use the brakes, maintaining them, and minimizing/avoiding the need to use them in emergency situations.

I've done with my ebike the same thing I've done with all my bikes. I've ridden it up to speeds past 30 mph and observed how well the bike slows down. Can I brake near the limits of skidding and/or flipping over my handlebars? If so, I'm fine. If not, time to fix stuff ... and ride slower until things are "fixed."
 
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

Nope. Instrumented tests by German bike magazines have demonstrated that only the very best disc brakes perform as well as normal rim brakes at energy dissipation, and unlike rim brakes they can't be upgraded with a heavier rim.

In the last twenty years, discs have developed better feel, and the low end of discs has become much less awful. But there's an insurmountable physics challenge for them. You can't make 150g of stainless steel with a low heat capacity and low thermal conductivity do the job of 1000g of aluminum with excellent heat capacity and thermal conductivity, especially when the aluminum is arranged in a rotor three times the diameter. Rim brakes are disc brakes-- but with much bigger, much heavier, qualitatively better rotors.

I made the rim brakes in my photo, before Shimano V-brakes had even been brought to market. Nothing yet has come close to them; definitely not discs.
 
I like the way Chalo puts the brakes on discs. Makes a lot of sense too, when put it in those terms; heat dissipation of 1000g rim vs 150g disc. Plus probably surface area. I never been a fan of them hydraulic brakes, the bb5's are blah but the bb7's are good for discs, still a lot of money vs rim brakes.
 
Chalo said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

Nope. Instrumented tests by German bike magazines have demonstrated that only the very best disc brakes perform as well as normal rim brakes at energy dissipation, and unlike rim brakes they can't be upgraded with a heavier rim.

In the last twenty years, discs have developed better feel, and the low end of discs has become much less awful. But there's an insurmountable physics challenge for them. You can't make 150g of stainless steel with a low heat capacity and low thermal conductivity do the job of 1000g of aluminum with excellent heat capacity and thermal conductivity, especially when the aluminum is arranged in a rotor three times the diameter. Rim brakes are disc brakes-- but with much bigger, much heavier, qualitatively better rotors.

I made the rim brakes in my photo, before Shimano V-brakes had even been brought to market. Nothing yet has come close to them; definitely not discs.

Would love to see a link to ANY test that shows that: rim brakes can stop your bike better than disc brakes. Please. Someone enlighten me.

I get that in some abstract way, rim brakes should work better, because that disc is so small! How can it work? I don't know, but it does!
Maybe forget about the excellent heat capacity and thermal conductivity, and just go out and ride two bikes back to back on a long descent, one with decent rim brakes of any variety, and one with decent hydraulic disc brakes. And please, please, please show me ANY REPUTABLE TEST ANYWHERE that shows a rim brake stopping better. Not energy dissipation. But actually stopping the bike. Don't you think that if rim brakes worked better, they would be used somewhere, anywhere, on things that go fast and need to stop fast? Race cars? Motorcycles? Hello?

This is an absurd argument, and would be amusing except that it is pretty serious misinformation for people who may not have much of a background with cycling. I applaud you for making the rim brakes in your photo, looks like a very neat project, especially if before v-brakes. I like cantis of all types and I use them. But the idea that they can stop as well as a disc brake with a caliper is just ridiculous.
 
wturber said:
When you say, "Way, way better" you open up lots of room for debate.

Ok, debate is good. But they are way, way better for all the reasons I described earlier: wet/grimy rims, untrue wheel=bent rotor, less modulation, tire blows up on tandem.

"Absolutely superior" That's an interesting description. Semantically we could say it is no different in meaning than just "better." But I guess "absolutely superior" sounds better than ... er I mean ... sounds absolutely superior to "better."

Really??

That said, I've only had two bikes with cantilever brakes and I really didn't ride those particular bikes all that much.

Bingo.

Anyway ... back to my main point. I'm a bit tired of the hype. Bicycles are fundamentally limited in stopping power by their relatively high centers of gravity. They are then further limited by the skill of the rider applying the brakes and the limited size of their tire contact patches.

When it comes right down to it, standard bicycles are fundamentally pretty flawed when it comes to braking. Apply your brakes poorly and you fly over the handlebars or skid a tire and stop really poorly, or crash if the tire you skidded was the front one on a loose surface. IMO, the trick with bicycling in general is to simply avoid situations where you must stop super quickly (panic) to begin with ... because that's not a strong point for bicycles. They don't have full-slam-on-anti-skid brakes. (Though maybe they should?!?) And for this reason I see no reason to hype up or get very excited about the issue much either way. Other issues are typically far more significant than whether your brake design happens to be rim or disc. In most riding environments/situations (not all), I don't think it really matters that much if you've already taken care of the really important things such as knowing how to use the brakes, maintaining them, and minimizing/avoiding the need to use them in emergency situations.

Yeah. So, dear future readers, if you do want to stop quickly and reliably, if you want the best stopping power, if that is your goal, then you should know that disc brakes are absolutely, positively, without a doubt, unarguably, and demonstrably superior to rim brakes. If you want to think in engineering terms about poor design, heat dissipation, center of gravity, and contact patches, then maybe just minimize/avoid the need to use your brakes so much.
 
Chalo said:
Nope. Instrumented tests by German bike magazines have demonstrated that only the very best disc brakes perform as well as normal rim brakes at energy dissipation, and unlike rim brakes they can't be upgraded with a heavier rim.
So you can't upgrade a 160mm disk to something better/heavier? Really?

I have no problems with rim brakes. I've had several ebikes that use V-brakes in the rear and disks in the front (solves problems with caliper clearance.) But your claims are nuts.
 
billvon said:
Chalo said:
Nope. Instrumented tests by German bike magazines have demonstrated that only the very best disc brakes perform as well as normal rim brakes at energy dissipation, and unlike rim brakes they can't be upgraded with a heavier rim.
So you can't upgrade a 160mm disk to something better/heavier? Really?

You might think the difference between a 125g, 160mm rotor and a 180g, 203mm rotor is significant. And maybe it is, if you're running near the limits of what a safety-critical system can do for you. But with a rim brake, you can jump up from the typical 400-550g rim to almost however much you want. The rim being braked by my linear-pull brake in the photo above weighs over 900g.

At the pedicab manufacturer I work for, we tried to get our latest batch of disc brakes furnished with 2.3mm thick rotors rather than the usual 1.8mm rotors. The brake manufacturer refused, saying the calipers weren't compatible with their own rotors that were only 0.5mm thicker. So yes, I'm saying you can't really upgrade to significantly bigger heavier disc rotors. With the new six passenger pedicab we're making, we are using two front disc brakes, because no single bicycle disc is up to the job.

Note that the aluminum in a rim has double the specific heat and ten times the thermal conductivity compared to the stainless steel in a brake rotor. That in itself is a massive difference which largely accounts for the failure of discs in controlled tests to outperform ordinary old-tech rim brakes.

This thread is about bike prices and the perception that they are too high. There can be no doubt that maximum usable braking power is much cheaper to get with rim brakes than with discs. Rim-brake-only wheels are cheaper than disc brake compatible wheels, and stronger when all else is equal. That's another savings.
 
Would love to see a link to ANY test that shows that: rim brakes can stop your bike better than disc brakes. Please. Someone enlighten me.

I get that in some abstract way, rim brakes should work better, because that disc is so small! How can it work? I don't know, but it does!
Maybe forget about the excellent heat capacity and thermal conductivity, and just go out and ride two bikes back to back on a long descent, one with decent rim brakes of any variety, and one with decent hydraulic disc brakes. And please, please, please show me ANY REPUTABLE TEST ANYWHERE that shows a rim brake stopping better. Not energy dissipation. But actually stopping the bike. Don't you think that if rim brakes worked better, they would be used somewhere, anywhere, on things that go fast and need to stop fast? Race cars? Motorcycles? Hello?

This is an absurd argument, and would be amusing except that it is pretty serious misinformation for people who may not have much of a background with cycling.

Indeed. The Ford Pinto hatchback had "excellent combustibility" and "a low flame point" when rear-ended, but somehow these never made it as selling points. Since neither those heat-dissipating-demon rim brakes NOR those too hot to touch disk brakes ever get hot enough to start a fire, I think it makes more sense to focus on how well they stop a bicycle. But that's just me...
 
81forest said:
Yeah. So, dear future readers, if you do want to stop quickly and reliably, if you want the best stopping power, if that is your goal, then you should know that disc brakes are absolutely, positively, without a doubt, unarguably, and demonstrably superior to rim brakes.
Error by categorization and more hyperbole. Caliper brakes have been stopping bicycles quickly and reliably for decades. Disc brakes might very well have better stopping power on average. It's hard to say. I've yet to find a good, well designed study or test. But people don't have an aggregate average brake set. They have a specific one. And some specific caliper brakes might very well outperform some other specific disc brakes. It simply is not categorically true that all disc brakes are better than all rim brakes. The devil is in the details.

Further, the various tests I've seen are typically very poorly done with a very small sample of brakes and usually not done with a wide enough range of riders and situations to come to the conclusions you are drawing. One guy did a wet brake test by pouring water on his rims and disc ... and then braking on dry pavement!?!? I'll give him credit for essentially admitting it was a crap test.

81forest said:
If you want to think in engineering terms about poor design, heat dissipation, center of gravity, and contact patches, then maybe just minimize/avoid the need to use your brakes so much.

If you are riding a typical conventional bike in typical situations, then being road-wise and avoiding the need for emergency braking is more important than the improvement in braking that switching to a disc brake might provide. The issue isn't "poor design." The issue is that a higher center of gravity puts a ceiling on stopping performance. The trade-off is that the conventional bicycle provides an elevated and advantaged view for the cyclist and makes the cyclist easier to be seen by automobiles. So it seems sensible to me to focus on making sure I use those attributes of the design to good advantage.

As I said before, there are situations where a disc brake setup would seem to be a clear choice. There are also situations that can favor a caliper type brake. But for the vast majority of riders/situations, either will be just fine so long as it is of decent quality and well maintained.
 
81forest said:
But for Pete’s sake I can’t believe that anyone is still claiming that when it comes to effective stopping power, rim brakes are just as good (even better!!) than disc brakes.

The ONLY reasons to run rim brakes on an ebike are compatibly with your existing parts, or cost. And I do not understand the desire to save money on the most important safety component, for a bike that is way heavier and faster than it was designed to be.

If you want to consistently and reliably stop as quickly as possible, then it’s pretty simple...

The rim is similar to a disc the size of a rim and therefor stopping power can be very high :)

I like the Magura HS11 and HS33 hydraulic rim brakes and use them on some bikes for daily use. These Brakes are almost maintainance free. Replacing the brake pads once in a while and adjusting the brake pads (on the Lever) three times in a while is all that is needed. With the more modern Versions you don't Need any Tools for that, just your fingers.

That's it. No fading, no heat problems (for avarage usage), no noise, no bent discs, no brake pad adjustment problems, no change of hydraulic oil, no air inside, no braking in of new brake pads, no problems with grease and oil, simply nothing. If you want a brake that usually lasts 100.000km and 20 years this is a very good option and hundreds of thousands long term owners will agree.

Stopping power is high enough to bring your wheels to an imidiate stop, which is more braking power than you want.

This is with dry and clean rims.

If you ride in the dirt disc brakes are better, also for heavy downhill, but for the average daily use including speed pedelecs those rim brakes are very fine.

I also own and use bikes with v-Brakes (Deore), mechanical disc brakes (BB7) and hydraulic disc brakes (various, up to Magura MT5e)
 
Chalo said:
At the pedicab manufacturer I work for, we tried to get our latest batch of disc brakes furnished with 2.3mm thick rotors rather than the usual 1.8mm rotors. The brake manufacturer refused, saying the calipers weren't compatible with their own rotors that were only 0.5mm thicker.

New Magura rotors are 2.0mm thick
 
81forest said:
tomjasz said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

You are not taking into account the really crappy discs on so many bikes. BTW I have 26" discs.
Of course crappy stuff is gonna be crappy. But it does not cost that much to put some good stoppers on your bike. And it is money well spent!
But that’s what the market gives you, and the sales pitches twist less than critical riders into buying the BS that disc are superior simply by being disc.
 
Whatever a builder buys is the best, just ask. We live in a culture that has troubles with facts. And certainly can’t parse differences in usage and performance. A 4 piston disc on a 48v bike is like custom tires and wheels on a Yugo.
 
tomjasz said:
81forest said:
tomjasz said:
81forest said:
Rim brakes can be adequate, but discs are better. Way, way better.

You are not taking into account the really crappy discs on so many bikes. BTW I have 26" discs.
Of course crappy stuff is gonna be crappy. But it does not cost that much to put some good stoppers on your bike. And it is money well spent!
But that’s what the market gives you, and the sales pitches twist less than critical riders into buying the BS that disc are superior simply by being disc.

So you’re saying that we can find some examples of cheap disc brakes that don’t work as well as some nice rim brakes. Ok, I would agree. (FACE—>PALM)

Discs are superior not “simply by being disc”, they are superior BY DESIGN. A good hydraulic disc and caliper will stop better all day, every day, in every condition, than the best rim brake you can find. It just is what it is. Again, I have rim brakes on most of my bikes (because I love vintage stuff) and both of my ebike projects will have rim brakes on at least one end. I love rim brakes! When adjusted properly they are totally adequate. But I also ride aggressively on gnarly terrain and I’m not a Luddite, so my trail bike has disc brakes! The arguments that some of the posters above are trying to make are just ludicrous:

“My pedicab company can’t source bigger rotors, therefore disc brakes are too expensive.”

“You really should just avoid the need to stop fast, because bikes are not designed well for stopping because high center of gravity and rider limitation” (huh???)

“The cheapest disc brakes are junky, therefore disc brakes are hype.”

“You can build a bigger, heavier rim, but you can’t build a bigger rotor, therefore rim brakes are superior.”

Talk about Wtf!!!! Am I missing any salient arguments here?
 
tomjasz said:
A 4 piston disc on a 48v bike is like custom tires and wheels on a Yugo.

I'd go so far as to say that disc brakes on any streetgoing bicycle are like alloy wheels on a car-- they are regarded as emphatically but ambiguously "better" than steel wheels by non-technical people, even though they don't offer any practical difference in performance as they're typically used.

A propos the topic of the thread, dollar for dollar you'll get better braking and better serviceability from rim brakes. Disc have other benefits, but cost and performance are not among their generic advantages.
 
81forest said:
Talk about Wtf!!!! Am I missing any salient arguments here?

I'm sorry you have never bothered to try using effective rim brakes. But your lack of experience does not make your false blanket statements true.
 
81forest said:
Chalo said:
I'm sorry you have never bothered to try using effective rim brakes. But your lack of experience does not make your false blanket statements true.
:roll: I give up.
If you haven't tried both Kool Stop pads and a brake booster arch, you don't know what you're talking about when you make pronouncements about how good rim brakes are. To the nearest approximation, nobody who claims discs are always better has tried these cheap and easy measures.
 
Chalo said:
81forest said:
Chalo said:
I'm sorry you have never bothered to try using effective rim brakes. But your lack of experience does not make your false blanket statements true.
:roll: I give up.
If you haven't tried both Kool Stop pads and a brake booster arch, you don't know what you're talking about when you make pronouncements about how good rim brakes are. To the nearest approximation, nobody who claims discs are always better has tried these cheap and easy measures.

Oh man. Not sure if you read my earlier posts, but I’ll say it again: I love rim brakes, they are strong, reliable, and easy to maintain.

Yes I do use kool stop pads. I do use brake arches when they’re needed. I used some pretty cool Paul cantilevers for cyclocross before v-brakes came out. Also used the hydraulic magura rim brakes, which were so awesome. When linear pull brakes came into the market, I could not believe how strong they were! One finger lock up, big long controlled front-wheel stoppies going downhill, it was amazing! My tandem has xtr v-brakes with amazing stopping power.

None of that changes the fact that disc brakes are a better design for stopping a bike. If you don’t need or use the strongest braking ability available, which many/most people don’t, you will be fine with rim brakes. But please don’t pretend that they work better, or as well, as a decent hydraulic disc and caliper.

Even affordable-level discs like Shimano SLX are better than any rim brake out there. In any condition, no matter how muddy or steep it gets, they just have better control and modulation. It’s never necessary to use more than one finger on the lever. While that can be said about the best v brakes as well, linear pulls still require more force to actuate than disc. More force to actuate equals less sensitivity and modulation.

You really think that the complete absence of rim brakes from every single decent mountain bike on the market is just hype? Boost spacing might be hype. Disc brakes are there because they work better.
 
I can say this on the subject.

I have never had a rim brake fade out on me due to overheating.

I have had several disc brakes fade out on me due to overheating.

Disc brakes existed for several decades on motorcycles before making their way to bicycles, if rim brakes were so deficient I think this would have happened much sooner.
 
dustNbone said:
Disc brakes existed for several decades on motorcycles before making their way to bicycles, if rim brakes were so deficient I think this would have happened much sooner.

That might have had something to do with how laughably awful some early bicycle disc brakes were.
1975-shimano-disc-brakes.gif


I got my first discs in 1992. They were regarded as the best available at the time. They were more or less OK-- about what I have come to expect from good broken-in drum brakes with appropriate levers. But they were much more expensive than that. And much noisier.
1114066d1483675218-mountain-cycles-san-andreas-mountain-cycle-2-web.jpg
 
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