Redbullet

I got an issue with SRAM Rival hydraulic brakes (road bike): the front brake lever touches the handlebar well before applying full braking. The rear brake lever works better, but it already goes close to the handlebar at full brake.
The bike is 11 months old and has only 2200 km of riding on flat roads with minimum normal braking, thus, there is no important wear in pads and disks. I doubt it leaked brake fluid to require bleeding, nor it got any kind of damage.

Is there a simple solution available to fix the issue?

Polaris OBark

Did it previously work correctly? If so, you likely have some air or water in the brake line, so a bleed might help.

If it never worked correctly, you might need to adjust the throw of the levers, or re-position on the handlebars.

Redbullet

Yes, they worked ok as new. It is strange that both levers fail in the same way after 11 months of very low usage.
I was thinking I can avoid bleeding, as it looks to be a relatively complicated procedure to carry very often. Are hydraulic brakes so sensitive that they need bleeding at less than 11 months interval, even if they were rarely used?

Polaris OBark

Shimano uses mineral oil, and they are rather low maintenance, unless they leak or something.

SRAM uses DOT fluid, which is hygroscopic. It absorbs ambient water vapor much more easily, and can result in what you are describing. (Or you might simply have a very slight leak.)

If you don't feel confident bleeding them, pay a bike shop to make them right.

There is one other thing I should have mentioned right at the beginning: It could be as simple as brake bad wear (and/or rotor wear). Check those before you do anything drastic.

Redbullet

No, there can not be wear for sure after 2200 km riding on flat roads with rare and mild braking.
With regards to that "Dot 5.1" fluid: SRAM fluid is roughly 8 times more expensive than DOT 5.1 sold by other reputable brands (probably for cars). Does it worth spending 8 time s the price for SRAM version, or is it the same with les expensive versions on the market?

Polaris OBark

When my levers get close to the bars, it is almost invariably because the pads have worn thin (Shimano Ultegra in my case).

I've never had brake pads last anywhere near 2200 km riding; admittedly not at all flat. It costs nothing to pull them out and take a look, and if you have worn them down, you will eventually ruin the rotors, so it is worth keeping track of this.

I think any DOT 5.1 will work; just make sure 5.1 is what is required. The bleed kit will make it easier/possible, but the fluid is corrosive. Wear eye protection and gloves and wipe up any splashes or spills from the bike immediately.

Or just get a bike shop to diagnose the problem in person, and do whatever is needed.

mpetry912 

you can shine a bright light on the pads inside the caliper and see if they are worn but sounds to me like it may be bleed time.

/markp

choddo

It’s not flat (or dry) around here and I’ve never had pads last less than at least 5000km I don’t think? But worth a look.

Bill Kapaun

https://epicbleedsolutions.com/blogs...after-bleeding

tFUnK

Either pad wear or (and) needing to be bled. In my experience it's more likely caused by pad wear but only you can tell us what's the culprit in your case.

I've always felt like disc brake pads wore quicker than rim brake pads, but then again I've not tried all the various disc pad compounds out there.

dedhed

Assumed or measured/verified no wear?

Yes, the simple solution is to methodically diagnose the problem beginning with the simple free task of verifying pad/disc wear and moving on to the next most likely cause.- bleeding.

Redbullet

SRAM reccomends changing pads when their thickness is below 3mm. I have just checked: 3.6-3.7 mm. I ordered a bleeding kit to have it available. I assume that bleeding would solve the issue, since it is somehow as a total reset action.

But I also found "Disc Brake Pad Advancement Procedure" in SRAM manual. I followed that procedure in a modified way (I performed it with the pads installed). This procedure probably made the pistons to keep a more advanced position (maybe 0.1-0.2 mm?). I got visible relief, thus, I'll give it a test for a ride or two.

It looks like disk brakes are not that simple at they seem to be...

bboy314

I would never consider bicycle components that rely on DOT fluid “simple”, though, like anything, once you get some experience working with them it’s pretty straightforward. Though SRAM hydraulic brakes are notoriously more finicky than others.

Polaris OBark

I just thought of one potential problem: A large open bottle will start to absorb ambient water vapor, so unless you have other uses for it, it might not be as cost-effective as you think.

Iride01 

Not using them can be a sure sign that odd-ball things will go bad when put to use. Seals might have been so use doing nothing that they were stuck and let some air to get in the system or fluid to escape during those first few activations when put back into service. Or environmental conditions might have caused them to bring in air while stored as the seals weren't getting regular use to keep them limber. Might have been just temporary till they go moving again and limbered up or the damage may be permanent and you'll continue to have issues.

Redbullet

I get the point. But the bike is only 11 months old and the longest period it stayed unused was 2 months (winter period, 100% riding only on trainer with another bike). I don't think that disk brakes are that sensitive that they break so easily. I would rather understand now that disk brakes really need some maintenance works regularly at relatively short periods, maybe especially SRAM.

Gone are those days when I rode 20000 Km, including some hard descents, with zero maintenance rim brakes, other than one change of front pads at the end of the period... Those brakes were SRAM also.

Bill Kapaun

What's "NEW" thickness? If appreciably more, you might want to install new pads if going through the trouble of the bleeding process.

DOT 5.1 fluid is DOT 5.1 fluid.
It's a specification.

Polaris OBark

Well-punned.

Redbullet

Yes, I was in a rush and didn't read it. I can add a few more if necessary...

Iride01 

It might not be there is anything you could have done differently. Possibly the issue is completely unrelated to anything we discussed here. My bike is now 4 years old and I've done absolutely nothing to my bike's hydraulic brakes except check the pads every great once in a while.

They don't have any bit of spongy feeling to them. I'm thinking I surely need to change the mineral oil, but on the other hand I worry I might start having issues if I do.

Mtracer

Pad wear could still be the culprit, even if the pads are not worn out. As the pads and rotors wear, the brake lever throw will increase. While you might expect that the pads should wear out before the lever hits the bars, who's to say how the brakes were initially setup.

soyabean

Pad wear has NOTHING to do with throw distance.

Please research this throughly or complete automotive school on how master cylinders work with caliper pistons before wrongly claiming how bike hydraulics work.

Polaris OBark

I've filled at least four of these...

Polaris OBark

My levers approach the bar when the pads are worn. When I replace them, they return back to where I can easily get a finger between the lever and the bar. It is highly reproducible.

Mtracer

That's my experience too, with Shimano brakes.