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Discussion Starter · #1 ·
I regularly drop 200m vertical in 450m distance, under brakes, and by the end they are "smoking"
~40% grade.
Bike is an XC Specialised Epic. Not a DH bike.

I rode a mates bike recently with XT M8000's on 200mm discs. It was a single finger but very grabby.

I have the stock Magura MTS on 180/160 w/ metal pads - they don't fade but they certainly feel the work, and it's a 2 finger job.

I'm reading reviews and such, like https://enduro-mtb.com/en/best-mtb-disc-brake-can-buy/

But I can't get a good idea of "one finger" brakes

Any suggestions? What do you have no matter what, only needs one finger?
 

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Biking Like Crazy!
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I had a similar occurrence on an extended narrow decent that I needed to constantly check my speed for safety and with 180 mm front and 160 mm rear on Hope X2's I really had to squeeze very hard with 1 finger and then went to 2 fingers as my hands got tired.
I re-rode the same trail 3 days later after putting a 180 mm rotor on the rear and it was 1 finger braking all the down. Much more controlled braking I should add.

So try upping at least your rear rotor to 180 mm and try that if the Epic can do that.

XT brakes brakes have servowave levers that can be grabby or on/off feeling.
Your brakes should have better modulation.
 

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200mm/180mm is my go to again. Thought that 180/160 was ok, but it wasn't. Made the mistake of buying a 2nd 180 for the rear, still not nearly as good as the 200/180. I say it was a mistake because I should have just tossed the 180 on the front out back & added the 203 up front as the first option. But I didn't. After that I built up a 2nd bike with a 203/180 and the 180/180 just didn't cut it after that. Now both bikes have 203/180 & it's great. Plenty of power when I need it, still plenty of modulation, just takes a lighter touch that is easy to get used to.

Takes a minute to get used to the 200 or 203 up front, but after you get used to it a 180 up front will feel under powered.

If you can fit a 200/203 up front do it & put the 180 in the back.

XT M8000's on one bike older XT M785's on the other.
 

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At that vertical distance you just need a bit more power. If you were doing longer runs or repeated shuttle runs then you'd really need to step up to a big brake.

The upgrade order should be pads, rotor size, then calipers and levers. I'd try a high-end sintered (fully metallic) pad like Jagwire Pro extreme sintered. After that I'd jump up in rotor size and if you're riding really steep descents then I'd go with equal size rotors if possible. Everyone knows the front tire can deliver more braking force, but what they seem to forget is that goes out the window when you're turning. Which is why on long steep descents you use the back brake a larger percent of the time.

Btw, I run Sram Code RSC with 200mm rotors on my enduro bike. Plenty of power and fade resistance over hours of lift access DH.
 

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Don't squeeze them so hard. Trite, but true. They have plenty of power....which is why you felt them to be grabby.
Yep. I've been saying that for years. Every time someone tries a brake that's more powerful than they're used to they initially say "it's too grabby," "it lacks modulation," "it's too powerful," etc. I even recall hearing that when v-brakes replaced cantilevers. Then again when discs replaced V's. It doesn't (or shouldn't) take long for your brain to learn how to adjust your input.
 

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Don't squeeze them so hard. Trite, but true. They have plenty of power....which is why you felt them to be grabby.
Yep. I've been saying that for years. Every time someone tries a brake that's more powerful than they're used to they initially say "it's too grabby," "it lacks modulation," "it's too powerful," etc. I even recall hearing that when v-brakes replaced cantilevers. Then again when discs replaced V's. It doesn't (or shouldn't) take long for your brain to learn how to adjust your input.
Yes, I was going to post this exact same thing. Every time I let someone with 160/160 rotors with xc grade brakes ride one of my bikes, no matter what brakes are on it, they complain about the brakes being too grabby. Bullshit. I run strong brakes because I want to STOP and I want to be able to feather them to manage my speed. 160/160 brakes with 2 pot calipers and resin pads are just wimpy on long, steep descents.

Hell, I'm running Hayes Dominion 4-pot brakes with sintered pads and 203/180 rotors on a hardtail. 40% grades are steep AF. I don't do anything that steep (certainly not sustained), but I definitely have descents that drop more elevation and cover more distance. Plenty of opportunity for heat to build up and cause fade if the brakes I'm using aren't up to the job.

I have another bike with Shimano M9020 brakes with finned, sintered pads and 203/180 rotors and I don't think I would want anything smaller for where/how I ride. There are a few spots where I'm more or less maxed out on the power they can provide. I like running a bit below max on the brakes because it saves some hand effort and gives me a little extra braking power for an emergency stop where I might REALLY need it. Gotta run grippy rubber to make use of it, though. If you keep increasing braking power, you can eventually run out of traction on your tires and all the extra braking power in the world won't help you.

My wife yesterday was commenting on her brakes feeling a little lacking in the power department and she asked me to check them. She's only got ~500mi or so on them, so I'm not expecting her pads to be totally thrashed yet. She made that comment after riding a particular descent faster than she's ever made it, though, so I wonder if she was simply approaching the limit of her bike's braking capability. She might be getting a pad and/or rotor upgrade to give her a little more power to work with.
 

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One finger braking is a technique, but lever needs to be positioned correctly.

Sounds like you need 8" rotors front and back.

Sent from my moto x4 using Tapatalk
 

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I'm a firm believer in running powerful brakes. I've never been in a situation where I wished I had less brake but I've had plenty of times when I've wanted more brake. The larger, more powerful 4-pot brakes are better at heat management so they're less likely to pump up, less likely to fade, and will help spare your forearm muscles on prolonged descents.

The most dramatic brake fail I've had was coming down off of the Burro Pass segment of the Whole Enchilada in Moab where my 2-pot XT brakes just totally gave out, front and rear. They heated up so badly that I could smash the levers all the way to the bars and I'd barely slow down. I had to stop for several minutes to let everything cool down a few times. I'd totally roasted the pads and had to buy new ones that afternoon.
 

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As others have mentioned, larger rotors are the cheapest/easiest solution, as the increase in size almost directly relates to the additional stopping power.

So you may try that (the larger rotors) first with your current brakes. If thats still not enough power, then its time to step it up to bigger brakes, like the kind you'd usually see on a downhill bike. Look at brakes like the TRP Quadiem, Shimano Saint/Zee, SRAM Code (or equivalent, these are just some of the more popular ones atm). Any brake of that caliber should be able to handle a trail like that.

Anecdotal "evidence":

I just bought a set of TRP quadiems, and took them on my first ride this last weekend. While not near as steep as the trail you're mentioning, I did ~1650ft of descending in 9 miles, with the bulk of it in a 1.85 mile stretch, with 1150 ft of descent. Trailforks says the steepest trail I was on only had an average grade of 13%, but a max grade of 49%. I've got 200mm front rotor, and 180mm rear, and I weigh ~200lbs or so all geared up.

The brakes weren't burning, steaming, sqealing, pumping up, or even changing their behavior by the end of the ride. They clearly were able to "handle it".

With my old bike (160mm front/rear rotors, Tektro Auriga pro 2 piston brakes), the same ride had me changing the lever through mid-way through on the way down. They felt like they were "just managing it". Although not complete failure like some other posters have mentioned.

Good luck on your search :).
 

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Discussion Starter · #12 ·
There do seem to be different scenario's

1. Stop as quick as possible (like yesterday when I relised the washout crossing my wheeltrack at the bottom of a descent was a lot deeper than I thought

2. Slow down on a long fast run - this means dumping heat to air to avoid overheating. Luckily at 40km/hr+ wind resistance does slow you down

3. The interesting one. Super steep, ass basically touching back wheel, long hill, with terraces stopping any speed, scratching for traction on rear wheel. There is no airspeed, and no relaxing the brake pressure. They are on HARD for the whole descent. It's just a case of dumping heat into the rotors, pads and caliper. Some is dumped to air, but not enough. Rotors end up all sorts of dark colours from heat.

I have ordered 203mm rotors. Will swap 180 to rear, put 203 on front and advise

Thanks

Welcome to hills in Kyrgyzstan
 

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There do seem to be different scenario's

1. Stop as quick as possible (like yesterday when I relised the washout crossing my wheeltrack at the bottom of a descent was a lot deeper than I thought

2. Slow down on a long fast run - this means dumping heat to air to avoid overheating. Luckily at 40km/hr+ wind resistance does slow you down

3. The interesting one. Super steep, ass basically touching back wheel, long hill, with terraces stopping any speed, scratching for traction on rear wheel. There is no airspeed, and no relaxing the brake pressure. They are on HARD for the whole descent. It's just a case of dumping heat into the rotors, pads and caliper. Some is dumped to air, but not enough. Rotors end up all sorts of dark colours from heat.

I have ordered 203mm rotors. Will swap 180 to rear, put 203 on front and advise

Thanks

Welcome to hills in Kyrgyzstan
That's actually pretty accurate. That's why:

1. In isolation, basically any brake will do this.

2. Yes, many brakes will do this without any special consideration because of the long periods of time when the brakes are not in use, but resting. It allows them to cool.

3. This is the killer scenario right here. This is where thermal mass will trump all else. Larger rotors, bigger pads, higher volume brakes with more fluid. In many cases, the rotors really are the key. It's them and the pads after all, that generate the heat. They are, if you will, 1/3 of the friction surface - 2 pads, 1 rotor. The more heat the rotor will accept (and dump to air) the less heat the pads must take on. Eventually the pads will have to start transferring heat to the calipers, which heats up the fluid. This is, arguably, where finned pads become a good idea. Still, even going from the smallest brake pad on the market to the largest, it's a VERY small change compared to even going from a 180mm rotor to a 200mm. The amount of extra material cannot be matched anywhere else in the system.

As a note - yes, it's a SYSTEM. I'm not writing off big brakes, or better brakes or more pistons. I'm pointing out the best single thermal management improvement is rotors. I've dropped huge descents with Avid Elixirs (I know, right?) using larger rotors than people thought was cool. Riding with XC guys, the "big" guys ran 180 front and 160 rear to "keep it light". I reckon most of them could have dropped more weight than the rotor difference off their bikes by buying higher end pedals or something. Anyhow, I don't like over heating brakes. So I run big rotors. So, in the XC crowd I ride with a lot, I may not be cool, but my brakes are.
 

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3. The interesting one. Super steep, ass basically touching back wheel, long hill, with terraces stopping any speed, scratching for traction on rear wheel. There is no airspeed, and no relaxing the brake pressure. They are on HARD for the whole descent. It's just a case of dumping heat into the rotors, pads and caliper. Some is dumped to air, but not enough. Rotors end up all sorts of dark colours from heat.

I have ordered 203mm rotors. Will swap 180 to rear, put 203 on front and advise
At the bike park, everyone's DH bike with big rotors and calipers have discolored rotors. So that's very common for riding the terrain you're describing. Bigger rotors exert more braking torque and can hold more heat so they're one of the best upgrades. However, typically when you experience brake fade on an mtb it's pad fade, not fluid fade. So having pads with a really high operating temperature is something you have to have for riding this type of terrain. Also, tires with more traction help by allowing you to ease up on the brakes periodically and brake later before a turn or take the turns faster and use less brake.
 

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If you're going too slow for the pads/rotor/caliper to bleed any heat, that does become a problem.

The largest rotor I'm aware of right now, is the TRP 225mm rotor. Its 2.3mm thick though (.5mm thicker than a normal rotor), and has to be used with their new DH brake. The increased thickness is said to increase the heat capacity/decrease the operating temp of the brakes by 8%, plus the benefit of the additional 22-25mm of rotor diameter.

https://trpcycling.com/product/g-spec-emtb/

It was originally designed as an emtb brake, but Aaron Gwin is using them this year on his normal downhill mountain bike.

But its good news that the new rotors are on the way. That may be enough to solve your problem.
 

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Yeah, bigger rotors 203,180 is my goto on the enduro bike. Also i refuse to run anything other than sintered pads.

If thats not good enough then look at a brake upgrade. I'm running single pot xt's and they arent too grabby for trail riding. I do admit they are a little grabby for feathuring high speed manuals.... but thats real sensative ****!
 

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Metal pads are less grabby, but basically everyone gets used to shimano brakes pretty quickly. I think half way into my first ride with them, I figured it out.

Also, my entire SLX brake set was $89 bucks brand new. Hayes brakes are less grabby and probably have more power... but they're past $400 a set.

i would go straight for the rotors, 203/180, but keep your existing brakes for now. That almost always does it for most riders. If not, look at new brakes. I bet new rotors will solve your issue though. Maguras are good stuff.
 
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