Steering heavy under braking

Haynes

I'm sure the steering never used to feel like this. But now when i brake the steering feels heavy and reluctant. (bike is a trek madone, 54cm with a 110mm stem)

The headset was a little loose and i suspected that was the problem, ive adjusted it up and its improved a bit.

Is it normal for the steering to feel heavier when the front brakes are applied or is something else likely to be wrong?

JustRidecp

Bikes are like cars. If you try to steer when braking you'll understeer. Best practice is to scrub off speed before a turn and keep off the brakes as you go through it. Dunno if this is what you're experiencing.

Titanium

Brake before you steer! You should not be on the brakes mid-corner unless there's an emergency.

Haynes

hmmm, you could be right, may be ive developed a bad habit recently. Ive noticed it when going relatively slow through junctions rather than on rapid decents.

portuguese mike

Titanium wrote:

Brake before you steer! You should not be on the brakes mid-corner unless there's an emergency.

Absolutely - if you have enough grip to brake then you have enough grip to get around the corner. A tyre only has a finite x amount of grip at any time on a given surface and this has to cope with all the forces thrown at it such as steering or braking (and traction in the case of the rear wheel. There isn't a separate amount of grip available for each of these forces - they are cumulative. So if there is enough spare grip to apply braking then you are not at the limit of adhesion. if you are close to the limit then applying the brakes will very likely send you over it and cause you to lose the front end. so the safest thing as mentioned is to get you'r braking done before you turn in, much like you would in a car.

aracer

That is rather simplistic, and also ignoring the way racing drivers take corners. The fastest way round a bend is not to do it all at the same speed, but to enter faster than you can take the corner at and decrease speed through the corner - racing drivers also accelerate out at the end, but that doesn't really work well on a bicycle, so you should apex a bit late. You only have to corner a little less sharply to be able to brake as well, which allows you to carry more speed into the start of the corner than you might do otherwise, tightening up your turn towards the middle end as you slow down.

portuguese mike

Yes it was simplistic and deliberately so. its a complicated equation with many variables so i was just explaining the general principal. Your statement is also a generalisation in fact you're assesment of the fastest technique for a car around a corner does not neccesarily apply to all types fo car (eg a porche 911).

aracer

portuguese mike wrote:

Yes it was simplistic and deliberately so. its a complicated equation with many variables so i was just explaining the general principal. Your statement is also a generalisation in fact you're assesment of the fastest technique for a car around a corner does not neccesarily apply to all types fo car (eg a porche 911).

But explaining the wrong general principle - there is a fundamental difference between your position that you can't brake in a corner, and mine that doing so is the fastest way to corner. Yes my car analogy was a generalisation - doesn't change the way it applies to all bicycles. http://www.sheldonbrown.com/brandt/descending.html

ddraver

Certainly don't use the back brake - try some suicide grip or something...

portuguese mike

i didn't say you couldn't brake in a corner, just that it's safer not to. Yes it 's usually faster to trail brake into a corner until you settle into your approach to the apex but i stick to my point about not braking when you are at the limit mid corner - especially in the wet

andrew_s

I resolved a similar problem with the steering stiffening up under braking by fitting a new headset. The lower (cartridge) bearing was knackered.