[Closed] Why are mountain bikers always bleeding their brakes ?

is it because they are mostly technically inept, but like to take things apart to play with them, never making anything work properly due to an incomplete understanding?

Its a long standing theory of mine that the people who constantly go on about problems with their bikes are the incessant tinkerers, those who cannot & will not leave the bloody things alone - so, they're never quite happy, go and adjust it 'just a little bit' constantly and in the process enter a downward spiral of messing with things for the sake of it and making it worse, until the parts break.

sounds like i need to bleed my brakes this week as i have never done them in the 2 years i have had my bike! 😉

Anyone tell me what brake fluid I need for my Avid BB7 front disc brake please?

😉

man fluid

I bleed my hope mini monos on Sunday. This was because they were pulling to the bars on Sat, although on inspection (and sound!) they had no pads left either (Surrey hills mud killed them). Last bleed when I sent them to Hope in Nov 2011, and have since been on a few DH races, enduro races and a trip to Alps + my local riding. Brake fluid was very dirty (rear)! Why this was, I'm not sure, but it didnt look good.
They now feel bl**dy superb and I'm glad I changed it/wished I changed sooner.

We aren't. I've never bled my brakes.

At least most people on this thread are bleeding their brakes and not their breaks............... 😉

(BTW, 6 year old Hydro's on my HT, never touched except brake pads. 1 year old RX's on my Zesty, bled once as the "quick release" dry break connector sprung a leak. TBH, i've bled my seatpost more times than my brakes (as it's internally routed and keeps er, breaking....)

This thread has had the effect of making me think "Hmmm, perhaps I should bleed a couple of my brakes, and I went looking for fluid and maybe a new "bleed kit" over lunch" possibly the opposite of what the OP intended but cheers none the less...

As for the point about "motorcycle trickledown" and fork reliability, I'd echo what others have said, the more complex and expensive forks of recent years appear to have silly service intervals and require far too much faffing IMO.

The 2003 DJ3s on my HT have had very little attention, probably only a couple of oil changes and some fiddling with the damping ports, they will be a decade old this year (assuming they don't fall apart tomorrow).

Likewise my Boxxers have only had a handful of "Home Services" and get an oil change maybe every 6-10 months when I remember or they start to feel really bad, again knocking on for 8 years old, nowt fancy again...

in both instances I put this down to open bath simplicity and not too much unnecessary tinkering...

Brakes are a similar thing really, keep an eye on the pad wear and watch out for sticky piston but if they are working and nothing seems to be wrong there's a limit to the preventative maintenance you can really do on them...

Anyone tell me what brake fluid I need for my Avid BB7 front disc brake please?

This, only front and rear 🙂

Anyone tell me what brake fluid I need for my Avid BB7 front disc brake please

WD40, to free up that rusting, crud-filled sticky brake cable. HTH. 🙂

What you mean is: "Why do mountain bikers with Hope, Avid, Formula or Hayes hydraulic brakes always seem to be bleeding them?"

I thought I had Hayes..?

I bleed my brakes to remind me how much more fun it is than SETTING UP CRUDDY CANTILEVER BRAKES!
(I'm beginning to dislike my cross bike intensely. Can't even change wheels without faffing around with the CRUDDY CANTILEVER BRAKES)

I think you always see the advice is because it's a matter of eliminating the problems when all you have is a bit of information written on a forum saying "My brakes don't work".

Brakes are quite simple. If it's not a problem with the pads/ discs contamination, then eliminate the chance of air in the fluid, in which case the problem could be more expensive such as seals (which will degrade over time).

Mountain bike brakes probably get far more of a work out than your two examples. Also, it's almost impossible to get the air out of some systems and with turning them upside down, apply the lever etc can get small air bubbles in the system which then need bleeding out.

I've had various systems, My Hopes needed bleeding every 6 months. I bleed my Maguras once after having them for years. My XT needed a bleed from new but have been fine since. (Which also answers your question - things out of the box are never as perfect as they should be).

i spend more time bleeding magura brakes than I do riding the bike in the first instance. and its always a right stress....

You don't need to bleed Elixirs when the pistons don't retract. Just loosen the bleed screw at the lever and then push them in, then close the screw. Easy done.

I thought I had Hayes..?

Mate: Noticed how the levers no longer really retract when you let go? They'll be alright like that. But when it happened to mine, I got fed up with the constant disc/pad rubbing.

My remark was a tongue-in-cheek.

Mate: Noticed how the levers no longer really retract when you let go?

Why are mountain bikers always bleeding their brakes ?

More fun bleeding brakes than bleeding on about 26v29 or Which tyres for, or My frames cracked.

BTW, did i mention, my frame IS cracked ;-(

Brake fluid absorbs water from the atmosphere. I think most vehicle manufacturers recommend it should be replaced every three years or so.
However, bicycles and motorcycles usually use sealed reservoirs with a diaphragm, so there is no contact between the fluid and atmosphere.

Wrong, moto and bicycle brake systems do absorb water.

This is why a lot of club level moto racers/track day riders will change their fluid twice a year at least, to get the best heat performance out of the fluid. The top end guys I know will do a bleed before every race.

It doesn't seem to have been said...

Lots of people need to bleed their brakes often, because they do it badly... They do it with worn pads so the pistons can't retract fully when they need to fit new ones, or they leave air in the reservoir which inevitably gets into the pressurised system. (easily done, with some designs).

Most people don't seem to keep brakes for long enough for the fluid to go off, though, so that's less of a concern than with auto systems 😉

When I boil my brakes do I need to do it in a bag ? Will I need to bleed them afterwards?

I've cut several notches into my brake hoses to bleed them and they worked horribly afterwards. If it did work though, then surely you wouldn't have to do it more than once unless you cover up the notches.

They do it with worn pads so the pistons can't retract fully when they need to fit new ones

That is the best piece of design to come from the Avid stable in my view - the bleed block that doubles up as a pad separator. However, the fact they need such a comprehensive tool with each brake is testament to their reliability...

Mine get done once or twice a year. But they are 8 year old Shimano deore so probably not 100% airtight round the reservoir seals. Usually want bleeding after a few very rough rides or repeated bike inversions. . It was 4years before they were bled. Wife's Hayes are the same.

I have Deore brakes on my bike and have not bled them r changed the fluid in 9 years .They work fine if they get spongy I just pull the lever back using a toe strap and force the air out that
way

Avid ultimates on my bro's bike (which I'm currently borrowing) haven't been bled in 3 to 4 years.
It's down to the person I think, my mates forever Farting about with something, "brakes need bled" "gears need a tweak" "those tyres I said were ace are gash, need a high roller hans dampf black chilli one"