speshelite

So, my allez elite '15 was spec'ed with crappy "axis" dual pivots. I assume they're tektro's. They work, more or less, but modulation is awful, primarily because the brake arms are so flexy. They work well initially as the pads hit because of the dual pivot design, but when you squeeze the levers after the pads hit and bite initially, there's precious little additional braking power, regardless of how hard you squeeze.

After trying a bunch of adjustments (toe in, flat contact, changing pad clearance and angle) I just gave up and installed....



....mountain bike v brake pads! Kool Stop dual compounds! I had a few extra pair lying around from my mtb days, and I swapped out the hard and short stock pads.

The difference is Yuuuuuuge! Now, braking effort is darn near effortless (at least in comparison) Now, I can ease up on the hand pressure and modulation is good. Before, my knuckles turned whiter than a macron trump handshake.

The beauty of this upgrade is that it's

a) super cheap (didn't cost me a cent), will only set you back maybe $25

b) does NOT require a new frame like disks

c) at least a full POUND lighter than disks

These are dual compound pads so they should work pretty well in the rain as well, if riding in the rain is your kind of thing.

If you have tektro's or axis dual pivots or arent' especially thrilled with your name brand dual pivots, try swapping out for a pair of v brake pads. You may be amazed by your newfound braking power and modulation. I am so stoked now that I don't have to worry about safety and can apply a feathery touch to get full braking power.

You're welcome.

Tokwan

I still have on my year 2000 Giant Yukon SE the Avids Archrival Brakes. Stopping power is almost equivalent to
mechanical Hayes Disc Brakes!

kbarch

Thanks. I see from their website that they have a lot of different dual-compound pads. Any reason to think the V type is the key, or do you think replacing just the pads on another type holder would do the trick?

Campag4life

Even better, trash those Axis brakes which are awful and go to new Shimano dual pivot which are simply awesome. I ride them in fact on two Campy bikes. Axis brakes are some of the worst I have ridden in memory.

rpenmanparker 

There are plenty of excellent brake pads around these days, and intended for road bikes. No need to use MTB V pads. It is the compound after all, not the pad design that is usually important. Kool Stop and Swisstop both offer as good as anyone needs.

Seattle Forrest

Like most claims about disc brake weight, this probably isn't true. But I'm glad you're enjoying them.

WhyFi

Disc brakes ran over my dog and stole my girlfriend.

joejack951

Probably because they were riding caliper brakes in the rain and couldn't stop in time.

High Fist Shin

Try the triple pads...



Each color is a small, separate pad. One for normal conditions, one for wet and one for "extreme." Whatever that means.

I switched to these recently and the difference is like night and day. I swear that these brake as well as the disc brakes on my other bike.

-Shin

speshelite

I tried kool stop salmon cartridge pads as well (compatible with dual pivot pad carriers). Those were actually a downgrade. The combination of pad flex and caliper flex actually made things worse. The salmon pads are very soft and spongy. The primary problem with the axis brakes is not so much the design but brake arm flex. Adding flexy pads to flexy arms is a recipe for abysmal braking "power."

I doubt any cartridge pad works as well as the v brake pads. The v brake pads are nearly twice as long and are twice as wide (tall) as well. There is just so much more surface area to grab the rim with compared to a cartridge pad.

https://www.amazon.com/Kool-Stop-Compound-Mountain-Linear-Threaded/dp/B001CLSWKQ/ref=sr_1_1?s=sporting-goods&ie=UTF8&qid=1502742217&sr=1-1&keywords=kool+stop+v+brakes

speshelite

Glad you like your pads, Shin.

One thing I should note about the pads I installed is that they have a lip at the back which, IMO, hinder braking performance. They're too large and prevent the pads from hitting the rim flush which is necessary to max out stopping power.

I cut those off and this small change made a big difference for the positive.

I don't know the dimensions of the pads shin posted compared to the ones I use, but the v brake pads I'm using are far larger than standard cartridge pads for dual pivots.

speshelite

Ultegra Disc vs Mech how much weight - Weight Weenies

According to the owner of Fair Wheel Bikes in Tucson, AZ, the weight difference between rim and disc brake builds is in fact, about a pound or a little more (holding component group level as a constant and using stock components).

"We've done quite a few near identical builds using mechanical/mechanical, mechanical/hydraulic and electronic/hydraulic. You can move spec all over the place to produce a variety of results. If comparing two equal bikes setup for high end performance the weight difference is almost always 450-500 grams. Here's a comparison of two builds one in disc and one in rim brake, but using parts that represent the correct level. This is based on a straight Ultegra group vs a mechanical/hydraulic (685/Ultegra) setup. As mentioned it would be possible to do a lighter disc version, but then to be fair you could also do a lighter rim brake version and the differences would stay roughly the same.

Frame, Disc frame +30 grams
Fork, Disc fork, +40 grams
Skewers, Disc thru axles +70 grams
Hubs, Disc centerlock hubs +20 grams
Rims, Disc rims -70 grams
Rotors, 160mm centerlock with lockrings, +260 grams
Shifter/caliper setup +106 grams disc (The comparison here was Set 1, Ultegra shifter, Ultegra calipers with pads and moutning bolts as well as brake cables and housing compared to R685 shifter, 785 calipers with pads, hydraulic lines, fluid, mounting bolts but without any adapters which may or may not be required.)
Spokes +26 grams disc (based on the idea that disc front wheels need to be a min of 24 spoke but most rim brake fronts are 20, CxRay of course)

That puts the difference between these two builds at 480 grams, or roughly 1.1 pounds. That's the most realistic estimate we've been able to come up with and it's the one we use when talking with customers, "good rule of thumb, disc brakes will be about a pound heavier than rim brakes.""

speshelite

This is incorrect. The v brake pads I'm using are nearly twice as long and just about twice as tall as well. That's nearly 4X the braking surface.

I tried kool stop salmon cartridge pads which are designed for dual pivots. Performance was actually significantly worse, which I didn't think was possible considering how poorly the stock axis brakes work, for the reasons I outline above.

Seattle Forrest

Disc technology keeps evolving. This ^ is slightly out of date.

For example, it suggests that disc braking imposes a 70 gram frameset penalty. Cervelo’s best road bike (R5) is 20 grams lighter in disc than rim. Their next best road bike (R3) is the same weight regardless of brake system, down to the gram. We’re talking frame and fork here.

Enve’s SES 3.4 wheel with DT hubs (the ones I bought) is about 50 grams heavier in disc than rim.

Even at the Ultegra level (RS-785) hydraulic discs impose a 340 gram penalty for the entire groupset.

Lots of ways to build a bike. In this particular case, hydraulic discs add about 370 grams over rim brakes, about 3/4 pound, and we’re only talking about Ultegra stuff. Plenty of room to go weight weeny on that still.

speshelite

That's actually over 4/5 of a pound based upon your figures (.816 pounds).

Pretty easy to find dual pivot calipers which are about 3 oz. lighter than ultegra's however, which would raise the weight penalty right back up to, you guessed it, about a pound.

Campag4life

which reinforces the adage written specifically for the overwhelming advantage of caliper brakes:


An ounce of prevention is worth a pound of cure.

joejack951

One undeniable advantage to rim brake bikes especially in the rain is that they get lighter and lighter with use, as those pads scrape and grind away at that braking surface. When you can actually feel the weight loss from this is usually a good indicator that you should replace your rims.

kbarch

I'll take this opportunity to point out why I like rim brakes. Because the rims are already there, and always will be. Rim brakes are an elegant solution. Disks for road bikes? Perverse. I won't deny their occasional advantages, but I just don't find them significant, and I kind of feel sorry for the people who think they're necessary.

Jiggle

Bigly!

LOL at you guys suggesting he get rid of the Axis brakes and get Campy or Shimano. There is very little difference between manufacturers in the amount of force the calipers put to the rim. weightweenie designs excluded. The rest is all the pads.

SylvainG

Yeah, great brake pads indeed. Only my rear brake pads needed changing last Spring so I only bought one pair. Got them on a rainy day and changed them right away. I was therefore able to compare their effectiveness against my old brake pads still on the front wheel. Needless to say, I ordered another pair that same day to replace my font pads. Now have over 2000 km on them and they are still working great.

f4rrest

Lol at someone who's never experienced the upgrade.

It's significant.

Jiggle

f4rrest

You couldn't pay me to put the tektros back on in place of the NOS Dura Ace.

Same swisstop pads.

Seattle Forrest

So we agree, "more than a pound" is the old days, not the modern ones. It'd also be easy to use DA instead of Ultegra, and light weight rotors, to shrink that penalty down some more.

speshelite

You don't seem to understand that a single cervelo model is not representative of the entire road bike market.

Also, while a dura ace disk group is lighter than an ultegra disk group, a dura ace mechanical group is also lighter than an ultegra mechanical group. Therefore, you would not narrow the gap at all by moving up a group.

The conclusion still holds generally speaking: the weight difference is a pound generally speaking. There is variation from brand to brand and from model to model.


Summary:

1. you are mistaking one outlier (one extremely expensive cervelo model) for the industry average

2. you give an inaccurate (low) estimate of the weight penalty

3. you attempt to pass off hyperbole ("old days") as fact. Fact is, Fair Wheel Bikes gives a very reliable estimate of the average weight difference as of 2016.

4. you contradict yourself: data from 2016 is "slightly out of date" initially, then it is the "old days" when your errors are pointed out to you.