[Closed] Settle a debate about braking please

As you pull the brakes the front wheel gets more weight and therefore the tire compresses, tread widens and generates more grip while the rear gets lighter and the tire decompresses and generates less grip. So something like 70-80% of braking power generally comes from the front, but you should be using both to slow you down. The brakes boiling is usually a symptom of dragging brakes. Brake when you need to slow down, release for the rest of the time. Suspension works better and you go faster

Both together. Retains balance, provides greater stopping power, reduces chances of skids.

Front does 80% that's why you run bigger rotors up front.

Look at a moto gp bikes brakes, huge double discs up front and one small rotor out back.

Rear becomes even less efficient when riding downhill.

You could prove him wrong by riding next to each other and stopping as quick as you can but each only using one brake... don't chuck yourself over your bars though in an attempt to win.

I can't believe this question needs to be asked. Has your mate ever ridden a bike before?

I can't believe this question needs to be asked. Has your mate ever ridden a bike before?

🙂 Very much this.

Both together. Retains balance, provides greater stopping power, reduces chances of skids.

100% this, although I'll admit I have gone against this on one occasion, while teaching my parents to MTB, my mum was really struggling with which brake to use when doing short techy stuff so ended up saying only to use the rear brake (kept grabbing both brakes and sliding front out and crashing) BUT this was on short techy sections where speed gained was actually beneficial and now she's confident enough to use both brakes whenever is needed!

Boiling brakes = brake dragger

He doesn't need to change his brakes then but he needs to change his braking.

I can't believe this question needs to be asked. Has your mate ever ridden a bike before?

Sweeping generalisation is sweeping.

I seem to recall Fabien Barel running a larger rear rotor for dh back in the day as he dragged it more than the front.

Pretty sure he's ridden a bike before 😉

Front does 80% that's why you run bigger rotors up front.

That's a completely different question ... and a bit sledgehammer and nut.
If you just want to bleed some speed then your only using 10% of the brake power ...

only using the rear for speed modulation and only bringing the front in for emergency stopping is the proper way while I say mainly using the front with rear for added support is the right way - In general of course as specific trail elements might see no front brake use at all.

I think the last part is most relevant ... also of course depending what tyres you're running.

I tend to apply more back brake on loose, especially if its a buildup to a corner but that of course doesn't mean there is less front braking taking place ... just I'm applying more pressure.

Otherwise I use both more or less equally in terms of pressure for slowing down a bit (again meaning more actual braking is from the front) and might modulate a bit if for example the back was skipping or the front starts slipping ... or move my weight further back ...Of course if I want to shed a load of speed really quickly then I'll be as far back and heels down and give it lots of front...

So I'd say a simple rule either way is not really realistic and trail conditions and where/what are the deciding factor and as above boiling brakes are a factor of dragging brakes so its more a case of letting them off between than applying them.

If you're racing then more front = faster braking ... meaning less loss of time but that also carries inherent risks that might be worth an extra second racing but not on holiday.

Usage of the brakes depends on the terrain. If you are going down a slow steep rock and rooty trail you ain't going to be pulling that front brake hard.

Always front more, it's the one with the best grip, braking is about slowing not stopping the wheels.

OP - Does your mate have two separate brake pedals in his car or use his hand brake to slow most of the time whilst driving??

Problem is, he keeps boiling his rear brake out this week. He's blaming brakes,

As above its a good mix of both front and rear brake that's required for stability, grip, decent braking deceleration and keeping control.

I was always told front does most of the stopping (especially when descending) but you use both together for ultimate Control. Boiling a rear brake is from dragging it (usually!)

If I want to slow down, both brakes together, weight low, heels down. But, if I want to not go any faster (say through a rocky section that I need to keep some some speed through) then rear brake only works for me.

But, in the Alps all bets are off 😆 Some of the trails are so steep that it's both brakes all the time

I love all the armchair responses ignoring the fact he is in Pila and saying use the front, use your front brake in the wrong place on those tracks and your in for a painful fall.

As some more sensible people state its course dependant. You basically use both and work out which is best based on grip, position on the bike, everything.

Sounds like your mate is just worried about overbraking on the front so is over compensating. I know i often ruin my back brake in the alps as the speeds are so much greater than at home, so you end up unconsciously dragging the back brake. Its just something he needs to consciously try and stop doing, and add in more front brake to help bleed off speed when needed.

Bit confused about these replies or I am doing it wrong.

How I brake on a bike depends on how I want the bike to react under braking. Braking harder on the front or rear wheel puts the bike into a different dynamic state.

Yup. Front brake scrubs speed fast but the dynamic tends towards jacknifing. The rear locks more easily but tends to the opposite. On fast stuff the front should be doing the work in straights; on super-twisty or bum-off-the-back steep technical stuff the rear is far more useful.

Yeah its all about the dynamic state man

Front primary...same as in a car. Change mates so his wrongdoing doesn't spoil your holiday.

He doesn't need to change which brake he uses, just how he uses them.

Stop dragging the whole time and brake harder for less time.

The additional problem with the rear only thing on steep downhill stuff is that you have limited traction so can't scrub speed as quickly and end up braking earlier and for longer (which also gives the brake less time to cool down between uses).

I definitely use a decent amount of front brake getting round the hundreds of corners on the Pila-Aosta freeride run.

Which of you is faster though?

ime there aren't any hard and fast rules

There are many situations where I use only the back, many more when I use both but not many where I use only the front

Anecdotally Zees on a fat bike means that braking has become a non-event

I use both almost all the time. I only use rear only when I want the back to move sideways. To avoid losing the front, I look at the trail and ride to where it looks grippiest. I find that most surfaces can take some front braking because you get so much more pressure on the front when braking.

But you can't simply hand out rules like 'only use one brake when going down' that's just daft.

If he's using the rear brake as his 'primary' brake he will of course be dragging it, it's not going to do much otherwise.

Tell him he's an idiot and move on.

I can sympathise - last few years running Shimano brakes (M615, XT) in the yearly Morzine Alps trip - no issues with power or fade or excessive wearing of pads.

This year the bike I was using had Guides - these might be adequate in the UK, but I found them completely overwhelmed in the Alps. Had to change the pads every 2 days when they were part worn so as not to have the lever come back to the bars after a few descents. Even after a very careful bleed. And I have large hands, so the levers are always at max reach.

Good trail brakes, maybe, but for me, not suitable for the Alps. Now being replaced. Guides will prob end up on Fleabay, with loads of part worn pads!

Brakes are 8 mths old.

Other bods in the chalet running guides also had similar issues. Those running Formula, Hope or Shimano - no issues whatsoever.

Had to change the pads every 2 days when they were part worn so as not to have the lever come back to the bars after a few descents.

I'm getting this with my Guide RS in the UK, though it is on an enduro bike that I've been riding on some lengthy descents in the Lakes and Scotland.

Most annoying anyway.

Your mate needs to learn to ride a bike. Braking is a subconscious thing.

i know that i can't go around corners properly without a back brake...... O

On a ride where my rear brake failed, i kept falling off in corners, which showed just how much the rear brake was being used (albeit subconsciously) to get the bike in the right shape to keep speed around corners.

Boiling brakes is only about WHERE and for HOW LONG you are braking.

Use them appropriately depending on the terrain (inc. ecological sensitivity), relative grip, and the need to decelerate. However general emphasis is definitely more on the front for me than a lot of my mates.

However you can always spot a wally locking up, skidding an d dragging their way around the hills - usually people who stopped riding bikes when they were kids.

You are much faster and safer with a front brake only, rather than a rear brake. Tell him to try it.

Generally use both and modulate each for whatever control you desire, but as mentioned 80% stopping power is upfront, rear is for extra control rather than stopping..

That must be why BMX racing bikes only have a rear brake then. The aim of a BMX race must be to be slow and crash.

They live on runways though.

That must be why BMX racing bikes only have a rear brake then. The aim of a BMX race must be to be slow and crash.

Cos BMX race courses are just like Alpine descents, aren't they?

I think the point is that it's horses for courses.

Front brake at the wrong time will mess you up. Rear brake at the wrong time will be under-effective. Some terrain demands more front brake, some demands more rear. (I don't know Pila.) Boiling your brakes is bad and it's wise to avoid it by adapting your technique when required. Simplistic judgmentalism about rear braking is silly. And so on 😉

I think we can probably all agree that the OP is about right, since he's noted the "context is everything" thing from the off and isn't boiling his brakes.

Meh 😉

All I know is that it's damn hard to achieve a good bedding in of pads on the rear brake, even hanging my bum off the back of the bike the rear wheel is locking before I think I've got any real heat in the pads.

Translating that onto the trail, if you're trying to scrub a lot of speed via the rear brake, without locking, you'll have to be pulling it gently from a long way out, sounds like a recipe for boiling brakes! 8)

Change mates so his wrongdoing doesn't spoil your holiday.

+1

Your mate is a dick.

On another note, how is Pilau? Thinking of stopping off there on the way home in August.

Big big bike territory or accessible on an "Enduro" bike?

@alpin, Pila's awesome on a trailbike. So is La Thuile, just up the road. I didn't take to Pila's bikepark but the trail down to Aosta is incredible.

For the OP, you could tell him I was doing full top-bottom nonstop runs at Pila on 2011 Formula The Ones with a 180 rear and never even a trace of brake fade, if that helps convince him it's not the brakes. And I definitely brake more than I should so it's not awesome skillz

Sounds like your mate has heard something or messed up in the past with the front brake and got a fixed idea about braking in his head.

What would be even worse than dragging the brake is if he was keeping his weight over the rear deliberately to keep traction for rear-only braking.

I once ended up doing a run at Mynydd Du DH with only a front brake.

It didn't go well.

i know that i can't go around corners properly without a back brake...... O

On a ride where my rear brake failed, i kept falling off in corners, which showed just how much the rear brake was being used (albeit subconsciously) to get the bike in the right shape to keep speed around corners.

I know what you mean....
A couple of times I've set off with a "partial" back brake figuring "I'm just following a 7yr old" and "80% is the front right"
By partial I mean still working a bit but not optimally ... but not enough to change the hose before in my head...

I actually found [u]I should have changed the damned hose[/u] .... much trickier than I'd expected only having a full front.... and perhaps especially following a rider who is faster on really twisty bits and slower on straight bits (24 vs 27.5 and bar length in my defence) ... from memory this was most noticeable in certain places.. and being stupid enough to repeat a 2nd weekend I remembered exactly WHY on the same spot... (It's not a difficult/technical spot ... excessively steep etc. just somewhere that having a front brake ONLY was decidedly hairy...

The front may have most of the braking power but the rear certainly has a great deal of the control in certain situations.

Locking the back far less of a problem, than locking, up at the front.
Touching back brake before corner, also settles bike, dynamically( as BEZ said )

But you still need to be doing your heaviest braking, at the front, on any reasonable surface.

Dread to think what would happen if your mate ever went touring with panniers

Yup, likewise I broke the rear off at the kinlochleven enduro one year and the final descent was a bit fraught- didn't really affect my stopping but did affect my bike handling

The interview with SRAM about their data logging brake forces with their disc power meter alluded to a new understanding on how important the rear brake is for subtle control. It was quite an interesting read.