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Mech disc brake with single piston = scam?

Old 08-09-22, 09:47 AM
  #26  
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Originally Posted by icemilkcoffee View Post
My other son's MTB has V-brake rim brakes, and I have to agree that it stops better than the single piston discs. I purposely looked for a disc brake bike this time around thinking it's progress and progress has got to be good, right? Wrong. Double piston hydraulic brakes are progress. Single sided mechanical disc brakes are invented to scam consumers who just knew they want to buy a disc brake bike.
While I don’t have a problem with rim brakes, your statement about single piston mechanicals is just wrong. The pads don’t “bend” the rotor if the brake is set up properly. The fixed pad is set so that it is almost touching the rotor and the piston moves its pad towards the rotor. The rotor may flex a small amount but the displacement should be fractions of a mm. If the rotor flexes more than 0.25mm (<0.0098”). It’s close enough that it’s hard to see light between the fixed pad and the rotor.

In my experience, a lot of problems that people have with mechanicals is that the brakes haven’t been set up properly. If the disc is set up like many rim brakes are with 1/2 lever pull before the pad hits the rim, the brakes will perform very, very poorly. The lever should be almost at wheel lock at half lever pull. The fixed pad is often too far away from the rotor as well. This article does an excellent job of explaining how the brake should be set up and adjusted.

You also said that the front caliper is “stiff”. There could be a couple of reasons. The first one I’d investigate is if the cable is corroded. That’s the easiest and cheapest thing to check and fix. Disconnect the cable and see if the caliper is still stiff. If it moves freely, replace the cable. But if the caliper is still stiff, that says that the caliper either needs a rebuild or replacement. On the Trek 3500, they used Zoom HL280 brakes which probably aren’t serviceable or they are cheap enough that you don’t want to spend your time servicing them. Get a Avid BB7 or a TRP Spyke, either one is a improvement over the Zoom, although the Zoom (and similar) can be made into a good brake if it is functioning properly.

Come to think of it, they should make a single sided hydraulic caliper. That way you can scam consumers who are sophisticated enough to buy hydraulic, but neglect to read the fine print about single sided vs double sided pistons. Hey bike manufacturers, here's another $3.50 savings for you! Go for it!
Jeeze, conspiracy much? You made the choice of buy a cheap bike…the cheapest in Trek’s mountain bike line. If you want a better bike with better brakes, buy a better one! Don’t buy a pig’s ear and complain that it’s not a silk purse. Granted the Trek 3500D is a whole lot better than a HellMart bike but, at $450, it’s not all that good compared to even slightly more expensive Treks. You get what you pay for.

There is no “scam” here. There is no “fine print” about single piston vs dual piston disc brakes.

Finally, this is coming from someone who it pains greatly to defend disc brakes. I don’t find them to be as magical as others find them but they aren’t all bad either.
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Old 08-09-22, 09:49 AM
  #27  
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Originally Posted by icemilkcoffee View Post
It's a Trek 3500. The more I look at this bike the more I hate it. The front fork has a conventional downwards opening, so hard braking could force the hub downwards. The brake levers have no reach adjustment- why would they omit this on a kid/youth bike? The headset uses caged ball bearings instead of catridge bearings. Good job saving $3, Mr. accountant. The handlebars is steel. Must have saved another $2 there.


1- I dont think you know what the word 'scam' means. It isnt a scam when it is clearly shown and known.
2- The bike is entry level so the components are basic/unimpressive. That is a really obvious result when the bike is entry.

Buy a new flatbar- basic aluminum ones are like $20 on ebay/amazon. A caged headset is fine, just grease it. If you want a better bike, buy a better bike.
Who buys a Ford Fiesta and complains that it doesnt have as nice an interior as a Lexus LS?
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Old 08-09-22, 09:53 AM
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IMO that style brake give the rotor/disc a bad rep. It works, but it's a cheap design. If you think it's worth the upgrade, I'd go with a dual pull mech caliper at minimum.
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Old 08-09-22, 10:06 AM
  #29  
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So what exactly is the scam? Tricking you into buying Paul Klampers for your $450 kids bike?
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Old 08-09-22, 10:15 AM
  #30  
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Originally Posted by cyccommute View Post
Single piston mechanicals have never been something that need constant maintenance nor constant adjustment. Nor have I found them to be worthless. Iím not saying that they are vastly better than rim but they arenít any worse.
And yet for some inexplicable reason you keep upgrading to Paul Klampers...The one & only exception of the single piston mechanical disc brake world that actually works well.


Iíve not been impressed with hydraulicsÖI find them far too touchy and the very opposite of ďwell modulatedĒÖand dual piston mechanicals donít perform any better than any other mechanical. Iíve had both dual piston and single piston. Neither is notably different from the other. They both stop wellÖbut then so do most any brake.
Brake levers are not binary toggle switches. They are analog devices that require operator skill & experience with a particular installation to use properly. But the beauty is you can configure the installation to be as grabby or as spongy as you want. Hydraulic 4 piston/203mm rotor will be a totally different experience than 2 piston/140mm rotors.

Perhaps your experience was with the former? Did you borrow a purpose built & customized down-hill mountain bike & think that experience spoke for all hydraulic brakes?

Dual-piston mechanical do indeed work better than cheap OEM single piston. One such way is the giant large rectangular pad cheap OEM's tend not to spec don't wear as quickly & have more surface area to better grab the rotor.

Another way they work better is they tend to warp rotors less, if ever & lever effort spent deflecting the rotor is spent applying braking force instead. Seriously, what engineer said: "Hey let's apply heat & torque to this thing we are bending & expect it to remain straight"? Come on man? Even you must see the poor design in that!

Are you talking about this case? That was a year ago. The parents claim the brakes were defective but the claim isnít that they didnít work but that they induced a wobble to the wheel when applied. Strangely, they said nothing about letting a 12 year old ride a bike that specifically says not to be used by anyone under the age of 18. These are extremely heavy bikes and a 12 year old may not have the strength nor motor control to keep one upright at speed with any kind of brake.
I wasn't there & neither were you. But I've worked plenty of Rad "bikes" & it was only a matter of time something as dangerous & cheaply constructed as they are would get somebody killed.

As to your experience, itís not one that Iíve shared. Iím not a small guy and I carry relatively heavy loads on a mountain bike on steep rugged downhills in the Colorado mountains where I can reach speeds of 30 to 40 mph. Iíve never had any kind of mechanical brake that failed to stop the bike. That includes both dual and single piston mechanicals. For that matter, Iíve never had a instance with any kind of brake where I thought the brakes would fail me. Iím not shy about letting gravity have its way with me.
https://yourlogicalfallacyis.com/anecdotal

Try doing 35mph down a 6% () grade & witness a green light turn yellow & at around 20mph find the brakes you had decide that a 15mph reduction of speed was enough work for them in the span of time it takes the yellow light took to turn red.

I'm not shy about staying off my brakes & as a truck driver, I know proper braking technique. They were cool, properly maintained & unused until that point of the descent. Any brake, even the foot I stuffed against the tire & seat-stay BMX style to eventually stop in the intersection should've been adequate for that scenario.

The OEM single piston mechanicals had a habit of behaving this way & after about the 10th failed emergency stop on an incline or fade to nothingness at normal cycling speeds, I moved to BB7's & 180mm rotors. Then over the years have upgraded from there.

Quite simply we've had different experiences & the variable is you are using the cream-de-la-cream of single piston's offerings & I'm talking OEM.

I admit, in recent years, OEM pads have gotten bigger. Most being the same form factor as Shimano B10S which are an improvement & may be passable performance minimum with 160mm rotors for most people.

Single piston mechanicals are safe, effective, and simple if properly adjusted and properly used. Most all issues Iíve run across (other peopleís bikes, not mine) have been issues with improper adjustmentÖeven on low end mechanicals. Properly tuned, even cheap mechanical discs are effective.
https://yourlogicalfallacyis.com/composition-division

Last edited by base2; 08-09-22 at 10:21 AM.
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Old 08-09-22, 10:17 AM
  #31  
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Originally Posted by icemilkcoffee View Post
My other son's MTB has V-brake rim brakes, and I have to agree that it stops better than the single piston discs. I purposely looked for a disc brake bike this time around thinking it's progress and progress has got to be good, right? Wrong. Double piston hydraulic brakes are progress. Single sided mechanical disc brakes are invented to scam consumers who just knew they want to buy a disc brake bike.
Come to think of it, they should make a single sided hydraulic caliper. That way you can scam consumers who are sophisticated enough to buy hydraulic, but neglect to read the fine print about single sided vs double sided pistons. Hey bike manufacturers, here's another $3.50 savings for you! Go for it!
And you continue to be that guy.
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Old 08-09-22, 11:25 AM
  #32  
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Originally Posted by cyccommute View Post
While I donít have a problem with rim brakes, your statement about single piston mechanicals is just wrong. The pads donít ďbendĒ the rotor if the brake is set up properly. The fixed pad is set so that it is almost touching the rotor and the piston moves its pad towards the rotor. The rotor may flex a small amount but the displacement should be fractions of a mm. If the rotor flexes more than 0.25mm (<0.0098Ē). Itís close enough that itís hard to see light between the fixed pad and the rotor.
Yes. That's what I did. I ended up using a feeler gauge to put between the pad and rotor on the stationary side and then tightened the mounting bolts. But it is a tedious process. The caliper likes to slip around as I tightened the bolts.

Originally Posted by cyccommute View Post
You made the choice of buy a cheap bikeÖthe cheapest in Trekís mountain bike line. If you want a better bike with better brakes, buy a better one! Donít buy a pigís ear and complain that itís not a silk purse. Granted the Trek 3500D is a whole lot better than a HellMart bike but, at $450, itís not all that good compared to even slightly more expensive Treks. You get what you pay for.
You don't see me complaining about the stamped steel riveted chainrings. Because these chain rings, although heavy, fundamentally work. They function as well as aluminum chain rings. It is a fundamentally honest cost cutting measure. There is no effort to disguise it as something else. Likewise my other son's MTB with v-brakes. Do v-brakes work as well as hydraulic discs? Nope. But fundamentally they are a sound design and not an attempt to mislead anyone. Again that would be an honest cost cutting measure. Same with 1X. An honest cost cutting measure. What you see is what you get.

It is fundamentally dishonest for them to put out something that looks like a disc brake system, but functions nothing like a proper hydraulic disc brake.... and then tout it as an upgrade over the old v-brake, which it certainly isn't. I don't like any cost cutting measures that works on the basis of 'let's hope the buyer doesn't notice this' or 'let's rope in the buyers who can't tell the difference'.
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Old 08-09-22, 11:41 AM
  #33  
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Originally Posted by icemilkcoffee View Post
Single sided mechanical disc brakes are invented to scam consumers
That way you can scam consumers
It is fundamentally dishonest
I don't like any cost cutting measures that works on the basis of 'let's hope the buyer doesn't notice this' or 'let's rope in the buyers who can't tell the difference'.
Caveat emptor, bro. If people are the unwitting victims of buying cheap gear, that's on them for not doing their due diligence. There's no conspiracy afoot.

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Old 08-09-22, 11:53 AM
  #34  
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What about those people that put out rim brakes that don't work as well as other rim brakes but otherwise look pretty much the same?

I've had some that stop really well and other lousy wet or dry.

I don't think any scammed me. And no conspiracy even though they didn't tell me they were lousy brakes.
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Old 08-09-22, 11:58 AM
  #35  
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Originally Posted by icemilkcoffee View Post
Yes. That's what I did. I ended up using a feeler gauge to put between the pad and rotor on the stationary side and then tightened the mounting bolts. But it is a tedious process. The caliper likes to slip around as I tightened the bolts.


You don't see me complaining about the stamped steel riveted chainrings. Because these chain rings, although heavy, fundamentally work. They function as well as aluminum chain rings. It is a fundamentally honest cost cutting measure. There is no effort to disguise it as something else. Likewise my other son's MTB with v-brakes. Do v-brakes work as well as hydraulic discs? Nope. But fundamentally they are a sound design and not an attempt to mislead anyone. Again that would be an honest cost cutting measure. Same with 1X. An honest cost cutting measure. What you see is what you get.

It is fundamentally dishonest for them to put out something that looks like a disc brake system, but functions nothing like a proper hydraulic disc brake.... and then tout it as an upgrade over the old v-brake, which it certainly isn't. I don't like any cost cutting measures that works on the basis of 'let's hope the buyer doesn't notice this' or 'let's rope in the buyers who can't tell the difference'.
You're trying really hard to turn a non-issue into something. Just stop. ANY disc brake design is an upgrade over ANY rim brake, period. Some more so than others but if properly set up even a cheap mechanical single piston brake will provide a bunch of power. And the companies that put these brakes on the market and most definitely NOT trying to fool anyone...except maybe tinfoil types like you.
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Old 08-09-22, 12:02 PM
  #36  
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These threads would be so much simpler if people just said I prefer disc/rim brakes instead of creating situations out of whole cloth to prove something

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Old 08-09-22, 12:06 PM
  #37  
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I have a bike with single-piston mechanical disc brakes. Thank goodness I found this thread, or I might have put another 12,000 miles on the bike without realizing that I'd been scammed.
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Old 08-09-22, 01:11 PM
  #38  
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Originally Posted by icemilkcoffee View Post
My other son's MTB has V-brake rim brakes, and I have to agree that it stops better than the single piston discs. I purposely looked for a disc brake bike this time around thinking it's progress and progress has got to be good, right? Wrong. Double piston hydraulic brakes are progress. Single sided mechanical disc brakes are invented to scam consumers who just knew they want to buy a disc brake bike.
Come to think of it, they should make a single sided hydraulic caliper. That way you can scam consumers who are sophisticated enough to buy hydraulic, but neglect to read the fine print about single sided vs double sided pistons. Hey bike manufacturers, here's another $3.50 savings for you! Go for it!
You bought a bike that cost about $450 when new. LOL. What the hell did you expect?
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Old 08-09-22, 01:36 PM
  #39  
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Originally Posted by base2 View Post
And yet for some inexplicable reason you keep upgrading to Paul Klampers...The one & only exception of the single piston mechanical disc brake world that actually works well.
I didnít upgrade to Klampers because I needed to. I did it because I wanted to. In reality, the performance difference between the Klampers and a set of Avid BB7 really isnít worth the price difference. I can afford the Klampers and like them but I have a bike with BB7s that work just as well. The BB7 might not be as easy to rebuild nor can the be swapped to a short pull if I want but they are completely adequate for even the demands I put on them as a heavy rider with a heavy load on rugged ground.

Brake levers are not binary toggle switches. They are analog devices that require operator skill & experience with a particular installation to use properly. But the beauty is you can configure the installation to be as grabby or as spongy as you want. Hydraulic 4 piston/203mm rotor will be a totally different experience than 2 piston/140mm rotors.
My experience with hydraulics was that they were binary toggle switches. A slight amount of pressure on the lever lead to locking the wheels. I never did experience the ďsuperior modulationĒ (i.e. ability to vary input to achieve controlled slowing and stopping) that hydraulics are supposed to provide. There is no adjustment to be made with the hydraulics I owned to make them anything other than grabby. They were early versions of hydraulics but the grabby nature put me off them. Mechanicals, in my opinion, mirror the real modulation of being able to achieve controlled slowing and stopping.

Perhaps your experience was with the former? Did you borrow a purpose built & customized down-hill mountain bike & think that experience spoke for all hydraulic brakes?
It was a 2005 Specialized Stumpjumper FSR Expert Disc 120. The brakes were Avid Juicy 7s which were well reviewed for the era. Never did like the bike muchÖit inchwormed horriblyÖand got rid of it for a 2003 S-Works Epic. The brakes were off long before I got the S-Works. My daughter noticed the same thing when I got her a dually with Juicy 7s.. Without promoting, she complained about how grabby they were.

Dual-piston mechanical do indeed work better than cheap OEM single piston. One such way is the giant large rectangular pad cheap OEM's tend not to spec don't wear as quickly & have more surface area to better grab the rotor.
Thereís your problem! Cheap mechanicals. Promax, Tektro, the Zooms above, or the Avid BB5 (which the others copied) are all a bit less effective because of the smaller pad. BB7 uses large rectangular pads as does the Klamper and the TRP Spyke/Spyre. The BB7 and Klamper also have pad adjustment on the moving pad which the BB5 and copies lack. It makes them easier to set up and keep in adjustment.

Another way they work better is they tend to warp rotors less, if ever & lever effort spent deflecting the rotor is spent applying braking force instead. Seriously, what engineer said: "Hey let's apply heat & torque to this thing we are bending & expect it to remain straight"? Come on man? Even you must see the poor design in that!
Warped rotors arenít an issue just with mechanical single piston brakes. They are a problem with all bicycle rotors. The issue is the thinness of the rotor and the heat applied to them. All that heat poured into a thin rotor that then cools unequally can result in warping of the rotor. Even cars can warp large rotors that are significantly heavier than a bicycle rotor.


I wasn't there & neither were you. But I've worked plenty of Rad "bikes" & it was only a matter of time something as dangerous & cheaply constructed as they are would get somebody killed.
I wasnít there. Neither were you, but you are drawing the conclusion (based on no evidence) that the brakes were at fault. I have read some about the complaint and the claim isnít made against the effectiveness of the brakes, only how the brakes induced a wheel wobble. That could also be easily explained by an inexperience, relative weak rider and a very heavy bike.

[/QUOTE]https://yourlogicalfallacyis.com/anecdotal[/QUOTE]

You know it really doesnít work to tell someone that they are committing a logical fallacy while committing the same logical fallacy, donít you? If my experiences are useless because they are anecdotal, yours are no more valid.

Try doing 35mph down a 6% () grade & witness a green light turn yellow & at around 20mph find the brakes you had decide that a 15mph reduction of speed was enough work for them in the span of time it takes the yellow light took to turn red.
I regularly do 35mph and more down 6% grades and have never had an issue slowing with any brake I use from cantilever to dual pivot road calipers to linear brakes to discs. 6% grade isnít all that steep. Try 20% grade with a bicycle/luggage/rider load that is dragging 300 lb and coming up to a rock ledge that you really donít want to ride down. Iím not unfamiliar with having to stop abruptly from high rates of speed in bad conditions. Iíve been mountain biking since the very early days with rigid bikes and cantilevers.

I'm not shy about staying off my brakes & as a truck driver, I know proper braking technique. They were cool, properly maintained & unused until that point of the descent. Any brake, even the foot I stuffed against the tire & seat-stay BMX style to eventually stop in the intersection should've been adequate for that scenario.
Given a very long experience with brakes, installing brakes, adjusting brakes, using brakes, and difficult conditions, I find it hard to believe that you brakes were properly adjusted if you have to jam a foot into the tire. Sorry but stopping a bike is very different from stopping a truck. Proper bike braking technique is very, very different.

The OEM single piston mechanicals had a habit of behaving this way & after about the 10th failed emergency stop on an incline or fade to nothingness at normal cycling speeds, I moved to BB7's & 180mm rotors. Then over the years have upgraded from there.

Quite simply we've had different experiences & the variable is you are using the cream-de-la-cream of single piston's offerings & I'm talking OEM.
I havenít always used high end brakes. Iíve used my share of OEM brakes. Iíve never run across any set of OEM brakes that I couldnít adjust so as to make them effectiveÖwith the possible exception of rod brakes on an Indian bike. If your brakes ďhad a habit of behaving this wayĒ on what sounds like a paved surface, Iíd say that the problem wasnít mechanism design but the mechanism set up.

I admit, in recent years, OEM pads have gotten bigger. Most being the same form factor as Shimano B10S which are an improvement & may be passable performance minimum with 160mm rotors for most people.

https://yourlogicalfallacyis.com/composition-division
Again, check that you arenít committing the same fallacy. Iíve adjusted thousands of brakes. Iíve used brakes thousands of times, personally. Iíve never had an issue with the bike not stopping in any condition.
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Old 08-09-22, 01:49 PM
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Originally Posted by icemilkcoffee View Post
Yes. That's what I did. I ended up using a feeler gauge to put between the pad and rotor on the stationary side and then tightened the mounting bolts. But it is a tedious process. The caliper likes to slip around as I tightened the bolts.
If your caliper is slipping around as you tighten the boltsÖassuming the bolts that clamp the caliper to the frameÖyou are installing/adjusting them wrong. The caliper should be clamped down on the rotor so that the rotor and caliper doesnít move. Once locked in place, the bolts can be tightened without the caliper moving. The link to the Avid adjustment works on any single piston mechanical Iíve ever run across and Iíve run across thousands of them at my local co-op.

It is fundamentally dishonest for them to put out something that looks like a disc brake system, but functions nothing like a proper hydraulic disc brake.... and then tout it as an upgrade over the old v-brake, which it certainly isn't. I don't like any cost cutting measures that works on the basis of 'let's hope the buyer doesn't notice this' or 'let's rope in the buyers who can't tell the difference'.
No one has ever said that mechanicals are going to function like hydraulics. If you want hydraulics, get hydraulics. But mechanical disc perform just as well as rim brakes. Iím a fan of rim brakes and donít consider discs to be far superior. They are a lateral move, not a vertical move. But I didnít consider v-brakes to be a vertical move from cantilever. Brakes on bikes work very well independent of the mechanism for the most part. But they have to be proper adjusted according to the idiocracies of the caliper. Poorly adjusted cantilever brakes are going to perform poorly. Poorly adjusted mechanical discs are going to perform poorly. Poorly adjusted hydraulics are going to perform poorly.

The other part of the equation is that even well adjusted brakes are going to perform poorly if you donít use them correctly. If you donít move back and down while braking, your stopping power is going to be greatly reduced.
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Old 08-09-22, 01:59 PM
  #41  
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[QUOTE][Single piston mechanicals is what got that little girl killed on the Rad bike from a few days ago. Single piston OEM mechanicals is what nearly got me killed in 2016 trying (& failing) to stop for a traffic signal on a simple speed limit descent./QUOTE]


I went through several sets of mechanical disk brakes before purchasing the Paul Klampers. The incident with the two young girls is and probably will stay a mystery. There are reports of the Rad Runner being hard to stop by other people. I wonder if the brakes were in proper working order. Stretched cables, worn pads. Did the girl have enough strength to apply the brakes properly.
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Old 08-09-22, 02:48 PM
  #42  
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Originally Posted by cyccommute View Post
I didnít upgrade to Klampers because I needed to. I did it because I wanted to. In reality, the performance difference between the Klampers and a set of Avid BB7 really isnít worth the price difference. I can afford the Klampers and like them but I have a bike with BB7s that work just as well. The BB7 might not be as easy to rebuild nor can the be swapped to a short pull if I want but they are completely adequate for even the demands I put on them as a heavy rider with a heavy load on rugged ground.



My experience with hydraulics was that they were binary toggle switches. A slight amount of pressure on the lever lead to locking the wheels. I never did experience the ďsuperior modulationĒ (i.e. ability to vary input to achieve controlled slowing and stopping) that hydraulics are supposed to provide. There is no adjustment to be made with the hydraulics I owned to make them anything other than grabby. They were early versions of hydraulics but the grabby nature put me off them. Mechanicals, in my opinion, mirror the real modulation of being able to achieve controlled slowing and stopping.



It was a 2005 Specialized Stumpjumper FSR Expert Disc 120. The brakes were Avid Juicy 7s which were well reviewed for the era. Never did like the bike muchÖit inchwormed horriblyÖand got rid of it for a 2003 S-Works Epic. The brakes were off long before I got the S-Works. My daughter noticed the same thing when I got her a dually with Juicy 7s.. Without promoting, she complained about how grabby they were.



Thereís your problem! Cheap mechanicals. Promax, Tektro, the Zooms above, or the Avid BB5 (which the others copied) are all a bit less effective because of the smaller pad. BB7 uses large rectangular pads as does the Klamper and the TRP Spyke/Spyre. The BB7 and Klamper also have pad adjustment on the moving pad which the BB5 and copies lack. It makes them easier to set up and keep in adjustment.



Warped rotors arenít an issue just with mechanical single piston brakes. They are a problem with all bicycle rotors. The issue is the thinness of the rotor and the heat applied to them. All that heat poured into a thin rotor that then cools unequally can result in warping of the rotor. Even cars can warp large rotors that are significantly heavier than a bicycle rotor.




I wasnít there. Neither were you, but you are drawing the conclusion (based on no evidence) that the brakes were at fault. I have read some about the complaint and the claim isnít made against the effectiveness of the brakes, only how the brakes induced a wheel wobble. That could also be easily explained by an inexperience, relative weak rider and a very heavy bike.

https://yourlogicalfallacyis.com/anecdotal

You know it really doesnít work to tell someone that they are committing a logical fallacy while committing the same logical fallacy, donít you? If my experiences are useless because they are anecdotal, yours are no more valid.



I regularly do 35mph and more down 6% grades and have never had an issue slowing with any brake I use from cantilever to dual pivot road calipers to linear brakes to discs. 6% grade isnít all that steep. Try 20% grade with a bicycle/luggage/rider load that is dragging 300 lb and coming up to a rock ledge that you really donít want to ride down. Iím not unfamiliar with having to stop abruptly from high rates of speed in bad conditions. Iíve been mountain biking since the very early days with rigid bikes and cantilevers.



Given a very long experience with brakes, installing brakes, adjusting brakes, using brakes, and difficult conditions, I find it hard to believe that you brakes were properly adjusted if you have to jam a foot into the tire. Sorry but stopping a bike is very different from stopping a truck. Proper bike braking technique is very, very different.



I havenít always used high end brakes. Iíve used my share of OEM brakes. Iíve never run across any set of OEM brakes that I couldnít adjust so as to make them effectiveÖwith the possible exception of rod brakes on an Indian bike. If your brakes ďhad a habit of behaving this wayĒ on what sounds like a paved surface, Iíd say that the problem wasnít mechanism design but the mechanism set up.



Again, check that you arenít committing the same fallacy. Iíve adjusted thousands of brakes. Iíve used brakes thousands of times, personally. Iíve never had an issue with the bike not stopping in any condition.
You sir have bested me.
It was wrong of me to cite your anecdote as such, provide a counter anecdote & then allow room for which your experience indeed may be correct to you, but not necessarily others & to concede that in the intervening 7 years things may have improved. To which you have indeed found my allowance of larger & more capable BB7's to be adequate for your uses.

It was wrong of me to place myself in your shoes & suppose that maybe you got your hydraulic disk experience from the extreme end of the spectrum in terms of performance & that may have colored your opinion. That, that is what actually happened to you is purely coincidental. Surely that was a random guess on my part.

It's not like I don't do this for a livin' or anything.

On this day, I award you one of the finest innernetz.
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Old 08-09-22, 04:57 PM
  #43  
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Originally Posted by Rolla View Post
Alternately, you can get hybrid brakes that use a cable to activate hydraulics in the caliper (like Yokozuna or TRP HY/RD); the pistons accommodate for pad wear. They can be expensive, but still less than some full hydro brakes.
These are definitely the way to go. You get many of the advantages of hydraulic brakes (dual piston, self adjustment, better lever feel) with the ease of setup of cable brakes (no bleeding required!) and you don't require specific brake levers to use them. I have a set of cable actuated hydraulics on my bike and I love them. Not sure why more people don't know about this option.
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Old 08-09-22, 10:50 PM
  #44  
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I have a pair of HY/RD brakes sitting in my tool box. The pistons blew out twice. The best stopping and easiest to maintain brakes I have ever owned are the Magura HS66 brakes still on my Tandem. Magura still makes the HS33.
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Old 08-10-22, 02:07 PM
  #45  
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Originally Posted by Rick View Post
I have a pair of HY/RD brakes sitting in my tool box. The pistons blew out twice. The best stopping and easiest to maintain brakes I have ever owned are the Magura HS66 brakes still on my Tandem. Magura still makes the HS33.
About the only way this can happen is to let the pads AND rotors wear completely. User error.
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Old 08-10-22, 06:27 PM
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About the only way this can happen is to let the pads AND rotors wear completely. User error.
The pads are still new as are the brakes.
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Old 08-10-22, 09:12 PM
  #47  
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Then tell us how you 'blew the pistons out twice'.
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Old 08-11-22, 08:47 AM
  #48  
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There are cable operated hydraulic calipers made by Juin-Tech. The two piston model is OK, but the 4 piston model is better. The 4 piston is apparently in short supply and sellers have added $100 to the normal price.

This is the cheaper F1.

https://www.ebay.com
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Old 08-11-22, 10:59 AM
  #49  
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Originally Posted by DaveSSS View Post
There are cable operated hydraulic calipers made by Juin-Tech. The two piston model is OK, but the 4 piston model is better.
These are also marketed under Crust and Yokozuna brands.
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Old 08-11-22, 03:19 PM
  #50  
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Here's the thing with brakes, all brakes: the ultimate power comes always comes down to the overall mechanical advantage in the braking system (be it mechanical or hydraulic), the leverage ratio of the braking surface to the tire, the coefficient of friction of the pad on the rotor, and how much input force you can supply. Nothing else really matters. With ultimate braking torque being the only thing considered, pad size does not matter, hydraulic vs. mechanical does not matter, rim vs. disk does not matter, one piston vs. twenty does not matter. The rider only has a finite amount of force they can produce with their meat sticks and a finite amount of lever throw to do it in. The brake designer/engineer's job is to carefully balance all of those variables to produce a braking system that works without excessive travel and produces enough output torque.

The one real advantage of hydraulics have over mechanicals is a significant reduction of friction since there are no cables and fewer pivot points. That reduction in friction means just a little bit more of your input force goes into producing meaningful work. And the self adjusting is a pretty cool bonus as well.
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