So when I put my rear brake on my wheel doesn’t fully stop (skid) and I can keep on pedalling when I have got it full on. And then the same happens with my front brake, I can have both of them bottoming out but I can still move the bike! Can someone please tell why this is?
1Be careful. If you lock your front wheel, you will go over the handlebars. The fact that you complain that you can't lock your front wheel while moving suggests that you've misunderstood what bike brakes do!– David RicherbyOct 20, 2018 at 10:22
1No I know it shouldn’t lock so I suppose I should just ask why my rear one isn’t– Morgan GriffithsOct 20, 2018 at 10:25
1Telling us what type of brakes you have, and the manufacturer and model if you know it would help us provide a specific answer.– Argenti ApparatusOct 20, 2018 at 11:45
And how do I bleed a disc brake– Morgan GriffithsOct 20, 2018 at 13:52
@DavidRicherby you go over the bars if your center of gravity adjusted by deceleration goes in front of contact patch or if you deliberately jump. On slippery surface like snow or sand or with low center of gravity it is easy to lock the front wheel, notice that you are sliding and then release the brake.– ojsOct 20, 2018 at 15:27
If you have mechanical brakes the most likely answer is that you brakes simply need adjusting or the pads need replacing.
Cable stretch and pad wear result in having to pull the lever further to move the pads onto the rim or rotor, eventually the lever hits the bar before sufficient pressure is exerted by the pads for effective braking.
If you have hydraulic brakes things are different as they are self-adjusting. In this case you most likely have air bubbles in the fluid and the brakes need to be bled.
If your brakes are adjusted properly, pad or rotor contamination could be the problem. Although it seems unlikely that both brakes got contaminated (unless you did something to both brakes that contaminated them).
There are plenty of videos and articles available that will show you how to adjust brakes. They are not hard to find.
I have disc brakes which are called XLC 17C-1 and they were bought from Halfords Oct 20, 2018 at 13:44
They are hydraulic disc brakes aswell Oct 20, 2018 at 13:50
1@MorganGriffiths if hydraulic then they need bleeding. Also check the pad wear. Oct 20, 2018 at 13:52
Check pad wear first I think.– gaoitheOct 21, 2018 at 0:37
There are a few potential causes. One could be that the pads need adjusting, generally on cable disc brakes where one pad is fixed and the other moves to press the rotor against it. In this case the fixed pad can be adjusted closer to the rotor.
Another is muck on the rotor/pads. Some seem to be much more prone to this than others. You can buy disc cleaner spray, but a bad case of contamination can mean you need to replace the pads as well as cleaning the rotor. You can also clean the discs with pure isopropanol or isopropanol/water mix.
But until sorted and tested (ASAP), ride very cautiously indeed. I've done a long ride with no useful back brake and it wasn't wise.