flik9999

Hey what problems would you encounter having a really strong front brake but weak back brake. Would you fly over the handlebars a lot without using a method of braking that isn't usual/

An example for the difference in brake would be a hydraulic disc brake on the front and weak side pull brakes on the back this is a vintage bike and want to know what problems I would encounter installing a new fork and hydraulic disc brake on the front but leave the back brake as it is.

My main concern is wondering if a combination such as this would be safe to ride.

Thanks in advance.

xenologer

Front brakes are normally stronger than back brakes.

As for your described situation, don't think of it as the front being too strong. instead think of it as the back being too weak.
-you're at no more risk of doing a header than anyone who has hydraulics on both ends.
(which is not much a risk at all if you learn to use a front brake properly)

cny-bikeman

The rear brake does absolutely nothing to prevent a header, and no matter what brake you use on the front it is proper technique that prevents such an occurrence. It is the weight transfer that is primarily responsible for front brakes having more of an effect, though the shorter cable length has some influence. Once most of your weight has transferred to the front wheel the back brake will merely make the rear wheel skid. The answer is to shift back and lower your body during hard braking, and to let up slightly on the front brake if you feel a skid beginning if you need to retain steering control.

flik9999

So its ok to go and install a really strong front brake with a new fork then? I cant install a good brake on back but front I can do.

Bike Gremlin

The only downside would be: harder to lock the rear wheel when you want to (for whatever reason - i like to do that sometimes in sharp turns, for fun ).

The up side would be: harder to lock the rear wheel accidentally, in case of a panic stop.


Proper braking technique explained:
Braking technique - Cycle Gremlin


One more thing: non-disc brakes aren't always bad. The greatest problem is slower reaction and harder modulation in the wet, but with good setup and good brake pads - they will lock the wheels no problem - just like well set up disc brakes would.

dsbrantjr

I have a bike with a Magura HS-33 hydraulic rim brake up front and Tektro CR-720 cantilever in the back. The front is MUCH stronger than the back. I find that the front/back balance is just about ideal for me. Many if not all automobiles have a similar front/rear braking distribution, either disc front/drum rear, or larger discs up front in an all-disc system. Many disc brake bikes also have larger rotors up front.

JohnDThompson 

Yes, it's fine. Plenty of fixed-gear cyclists ride with only a front brake. Putting a super-powerful brake on the rear is pointless, as the tire will start skidding long before the brake maxes out.

drlogik 

It's my experience also, and it's been addressed already, that braking technique is the most important aspect of good braking. As far as equipment is concerned, pad-based brakes usually stop well on back as well as front, especially higher end models like Ultegra and Dura-Ace. Disk brakes are great and need no further discussion. I see no issue with mixing brake types on front and rear but as has also been stated, a rear brake by the laws of physics, does not stop as well as a front brake and will not send you over the handlebar.

In short, practice good braking technique, keep your equipment in good shape and go out and ride!

DannoXYZ 

Due to physics (I can post equations if you want), the faster you want to stop, the more and more the front brake contributes to deceleration. There is weight-transfer to the front wheel based upon decelerating-G. At about 0.8g, you're at close to 100% weight on the front wheel with the rear hovering above the ground.

The weight-transfer is caused by the braking force and deceleration. Some people think that by reducing front-braking effort to get the back wheel on the ground will help stop quicker. But they don't realize that they've reduced their deceleration from 0.8 to 0.7g.

Here's a good article on braking technique: Maximum Braking: Move Back and Stay Back - IPMBA

- hands in drops
- straighten arms to resist deceleration (slightly bent elbow). This places all the braking forces on your palms, allowing your fingers to be free to modulate the lever-squeeze
- get low and slide back. Place your belly on the seat.
- ramp up front-lever force, don't just slam them on

Here's a decent example. I'd lower the butt more to lower C.o.G. to reduce the weight transfer and pitch-over torque.


Remember, at maximum deceleration-rate, there's zero contribution from the rear tyre. Practice, practice, practice!

flik9999

Thanks for the tips guys. Also are your standard rim brakes more powerful than the old brakes I have on my 80s bike. Or would I have the same braking power as say entry level V brakes if I fit alu rims to the bike. Im doing a delivery job and my bike can be in the 20kgs area (twice its natural 10KG weight) so need good brakes, would switching to alu rims increase my braking by much or should I focus on a stronger front brake?

In regards to fixies not using a back brake, I think you pedal backwards for a good back brake on those bikes.

hilltowner

Here's some advice on the subject from Sheldon Brown: Braking and Turning Your Bicycle

Bike Gremlin

My bike is 20 kgs unloaded. Steel frame, fat tyres, heavy locks...

In my experience, decent V-brake is a bit more powerful than a modern road bike brake. Modern road bike brake being a bit more powerful than an old road bike brake. All of them still, with good pads and alu rims, capable of locking the wheels when you set them up correctly and pull the levers with average human strength.

Whatever brakes you use, do test them in a safe area, re-tune, or ask for help when setting them up if you're not happy with performance, or not sure. If you ride loaded on a steep downhill, make sure to test them on a steep downhill loaded as well. Just to be 100% sure and safe.

gsa103

It's very common for mountain bikes to run a larger and more powerful front rotor.

DannoXYZ 

If you have steel chrome-plated rims, then the best bang-for-the-buck upgrade is to alloy rims. These will give much better pad-friction and braking-force.

Also don't have your brakes adjusted too tight so they grip immediately when you pull the levers. Have them engage about 1/2-way along the lever-travel. The fingers & hand-muscles exert higher squeezing force when the hand is almost closed. And they're better at modulating squeezing-pressure in the almost-closed position.

CliffordK

For a while Campy distributed a center-pivot side-pull brake for the rear, and a dual-pivot brake for the front, presumably giving a lighter brake for the rear, and a stronger one for the front.

I do a lot of my braking with the rear, especially drag braking on descents, so rear pads wear out much faster than front pads.

But, in an emergency stop, even with the best technique, one will tend to redistribute the weight to get more weight up front and less on the rear. Thus, it is harder to lock up the front wheel, except in slippery conditions, and easy to lock up the rear. Thus, a strong brake in the front than the rear might not be bad.

Quite a few department store quality MTBs were distributed with a front Disc, and rear V-Brake, I think.

cny-bikeman

That's not much of an upside, as the skid warns you that you need to shift weight further back or let up slightly on the front brake.

cny-bikeman

Physics and hand strength will ultimately limit how fast you can stop. Braking power will make a difference only if the older brakes (and pads) were insufficient to test the limits. Absolutely do not stay with steel rims. The bike weight difference is irrelevant, although if the added weight is in the rear it would actually help braking. Remember that while moving the bike weight includes you, so you are not doubling the weight that needs to be stopped.

Bike Gremlin

Depends on the way one looks at it. While I sometimes use deliberate rear wheel lock to test the surface grip, using rear wheel skid as a safety/warning during hard braking is not a good thing IMO.

Fist, during really hard braking, rear wheel can be lifted off the ground, without the front wheel loosing traction. So correlation: rear wheel slides, front will slide, loosen the brake - is often not correct.

Second: during a panic stop, it is better not to put a lot of force on the rear wheel, causing it to slide. Bicycle is more stable when neither wheel is sliding.

cny-bikeman

I did not say to skid the rear on purpose, nor that one should depend on the rear wheel skidding to adjust braking. Of course one should control the amount of hand force on the rear brake levers.

xenologer

Yes. Aluminum rims will drastically improve braking power. Absolutely do this.

Yes. V-brakes will most likely be stronger than your old brakes.
However this opens up the new question of Compatability with your old brake levers. V-brakes need different levers from road calipers and cantilevers.