How far back should your brake lever go?

[Tibbs]

Managed to get out on my bike this weekend, even if it was just ferrying stuff between my old and new places. Could have done with a trailer!

One thing it reminded me was that my brake lever comes right the way back against the handlebar, and when I 2 finger brake, I can't get it to brake hard (like for an emergency stop)even when I squash my fingers. It's fine for regular riding.

It was like that since I got it, and a service doesn't seem to have fixed it. I have an adjustable brake lever, but I don't want to take it out further, as it's at the limit of my reach already. There seems to be a lot of slack (probably more than an inch of pull) before the brake starts to come on.

Does anyone by any chance know a way to fix this before I get my Haynes and tools out?

Many thanks!

[jason1]

Id start with simple checks , condition of pads, disks , fluid level , leaks from all joints. Does sound as if you have air in system , do you know
 when fluid was last changed ? give it a bleed and see how lever feels . 

[Punkstig]

The lever shouldn't be able to come anywhere near the bars, even adjustable ones.
Check fluid level is above the lower limit (if its low check pads before topping up) then tie the lever back to the handlebar using a cable tie or similar for an hour or so, check all joints for any leaks, release it then re tie for as long as you can, overnight of possible.
If that doesn't help then I'd suggest a full rebuild of piston seals, fluid and if you dont have braided lines yet then might as well go the whole hog, the only reason I say that is these are your brakes, if anything is worth spending money on its your brakes,  and sooner rather than later!

[Dead Eye]

Sounds like air in the system to me. Only other thing would be significantly warped discs (pushing pads out) but that would cause many other symptoms that you haven't mentioned such as knocking

Bleeding the brakes should only take 10-15 minutes and its easy enough to do. A section of clear tubing is helpful, but realistically you can do it without it, it just gets a little more messy :P

Failing that, my bet is on brake lines - if its still the original rubber hoses then they could be expanding due to the pressure or bulging in a specific place. If that's the case, replace them ASAP

[stevierst]

Another thing people overlook is the piston seals. Over time they obviously break down and the outer seal gets distorted and smears between the piston, and cylinder acting almost like a rubber band. you squeeze the lever, pistons move, then you let the lever go, and the seal retracts, dragging the piston with it. you then have to pump the lever to get the piston moving again

 I had this on my sv650 where it was terrible braking, and until I changed the seals on my boxeye, it was starting to  happen there too. I bleed the brakes pretty regular due to the blue spots being quite sensitive, so I know it wasn't that.

its just something else to look for of bleeding doesn't work.

[red98]

try bleeding first as its only going to cost you a drop of brake fluid 

[Tibbs]

Thanks for the advice everyone - I didn't have chance to have look at it tonight, but I think it'll be a weekend thing.

I will tie the brake lever back in the mean tim and see if I get a leak anywhere.

[unfazed]

Change the brake fluid first, before you do anything else. Most people never change brake fluid and it should be done regularly. Brake fluid is hydroscopic (takes in water) and it deteriorates over time. If that does not solve it then a caliper refurbishment is in order.

[Punkstig]

Brake fluid is hydroscopic (takes in water)

Hygroscopic, just letting you know as I made that mistake, yup, its a g not a d!


Just a reminder- if you do change the fluid check how used the pads are as this will alter the 'max fill' point!

[unfazed]

Well spotted,  cannot even blame a slip of the finger as D and G and not together on the keyboard, close but not together.
The difference between Moisture and Water, Hygro and Hydro. Please accept my humble apologises.
Should really have said "attracts and holds water"

[darrsi]

Brake fluid is hydroscopic (takes in water)

Hygroscopic, just letting you know as I made that mistake, yup, its a g not a d!


Just a reminder- if you do change the fluid check how used the pads are as this will alter the 'max fill' point!

"It's greased lightning....." 

[Tibbs]

Right so a trip to Halfords later and I have a bottle of brake fluid and a brake bleeding kit.

Since I've never done this before, could someone confirm that this is the right way to do it?

Attach the tube to the bleed nipple
Open up the master cylinder
Pump the front brake
As the level drops fill up master cylinder with new fluid
When new fluid comes through at the bottom close off bleed nipple
Repeat for both sides of calliper and then the other calliper.

I bought 500ml of fluid, will that be enough?

I also have a jam jar for the excess fluid.

How do I allow for the wear on the brake pads?

Thanks

[Punkstig]

Right so a trip to Halfords later and I have a bottle of brake fluid and a brake bleeding kit.

Since I've never done this before, could someone confirm that this is the right way to do it?

Attach the tube to the bleed nipple
Open up the master cylinder
Pump the front brake
As the level drops fill up master cylinder with new fluid
When new fluid comes through at the bottom close off bleed nipple
Repeat for both sides of calliper and then the other calliper.

I bought 500ml of fluid, will that be enough?

I also have a jam jar for the excess fluid.

How do I allow for the wear on the brake pads?

Thanks

I'm glad you got all that stuff but first things first- before worrying about bleed nipples and tubes and undoing stuff try this-
Do NOT drain out any old fluid!
Unbolt the callipers from the forks and remove the pads,
Clean all the pistons but do not push them back in, then put the pads back in,
Undo the brake reservoir cap up by the lever,
Make sure the fluid at least covers the hole to the hose (which I'm assuming it already does)
Now slowly push the pistons back in by using the pads, hopefully you have a couple of adjustable pipe wrenches.
The idea is that any air in the system should be up at the top, probably trapped in the banjo attached to the master cylinder- pushing the pistons back in would continue to push the air up and into the reservoir, its easier this way than using the brake lever to pump air down through the fluid!


I only suggest this first because it uses physics as a friend!


Now, after doing this if you want to you can attach the hose to the bleed nipple in order to swap out the fluid for your new stuff.
Even with these specific one person brake bleeding hoses I have issues, but as far as I know before opening the bleed nipple make sure you put brake fluid in the jam jar and the end of the tube where the old fluid will come out is fully submerged in the fluid, this stops any air getting back into the system.
When you do open the bleed nipple do it very slowly as if you open it too much again air can get into the system!


You'll see when the new fluid comes out instead of the old stuff.
If you've done it this way then as the pistons are fully pushed in you can fill the reservoir to the max line, close everything off, cross your fingers and pump the lever to get the pads back to the discs.

[Dead Eye]

I've never had any issue bleeding the brakes even without a kit - I just have a length of hose I bought from B&Q about a year ago

I attach the hose and hang it off of indicator stem most of the time, the other end is in a container of choice - usually one of those plastic chinese takeaway tubs and I don't put any fluid in it either. Then, I crack open the bleed nipple and tighten it again so that it is just tight enough that I can undo it with one hand on the spanner. My other hand is then used on the brake lever and the process follows;

1. Open nipple
2. Squeeze brake lever
3. Close nipple
4. Release lever
5. Repeat from step 1

Until I am satisfied there is no air in the system. Make sure the reservoir doesn't empty, so keep topping it up with brake fluid. Hanging the hose above the caliper means that any air that escapes goes straight away from the nipple and if anything does go back in to the caliper it will only be the brake fluid that has just come out

On new lines I usually bleed all of the banjo bolts as well, but if you are just doing a fluid change / re-bleed then it typically isn't necessary

[Tibbs]

Went down to do my brakes and I don't have a spanner small enough for the bleed nipple!

Before I wander down to Halfords and buy a selection, does anyone know what size it it? Th smallest I have is 8 and that is too big.

[AN GOF]

its an 8mm on my 2003 blue spots.

[Tibbs]

It is an 8 - turns out my 9 was in the 8 spot...

I think this sums me up:



On the plus side, my brakes do seem better!

[elbrownos]

500ml is plenty. I changed front and rear with 300ml