This thread inspired me to bleed my brakes (DIY for the first time). I have Hayes 9s. After completing the bleed and inserting new pads I have pretty much zero clearance for the rotor to spin freely. The rotor will fit in between the pads but it's hard to get 1.5 revolutions of the wheel before it comes to a dead stop (same for front and rear wheels). I tried what Hayes recommends: using the Box end of a 10 MM wrench to push the pistons back but I don't seem to be able to get the pistons to move back at all. I also used a sparkling clean and thin putty knife (and cleaned with alcohol) to try and create some space as a makeshift shim (the Hayes Youtube video shows them using a metal shim for spacing). After all this does this sound normal? That is to say, do I just have to wait until the pads wear some or is this indicative of another problem. Also, thanks to all who have posted many helpful tips in this thread as it inspired me to bleed my brakes and other than this current problem I found the task to be relatively easy and fun! Thanks!
You may have too much fluid in the system. Crack open the bleed port on the MC then pry the pistons apart again with the box wrench. Close the bleed port then replace the pads then try again. You should have better clearance.
Finally got around to bleeding my brakes. The new clear fluid pushed out old fluid that looked like a yellowish-green urine sample. We'll see if the performance is better tomorrow.
Thats why you do that BEFORE the bleed. Tip your lever up, remove the bleed port on the lever, then compress the caliper slowly. Youll leak some fluid out of the caliper. Before you put the plug back in, give it a crop or two of fluid to make sure you didnt such a little air back in. OK this part will be easy..... ALL FLUIDS BREAK DOWN. Maintain your bike, the parts will last longer. It really cracks me up to see people saying" You dont need to bleed brakes" Specially when some of us are paying 200 plus per set of brakes. Why not bleed them once a year. Why not keep the items we are spending soo much money on in good condition so they last a long time and you get your moneys worth out of them. Glycol fluid, Mineral oil...... doesnt amtter they both need to be bled out regularly, no you dont get more time on mineral either. For the very reasonthat some will think you do..... WATER.... If you really want to get echnical, Glycol will last longer than mineral..... because it absorbs the water, instead of ending up with droplets of water in the system.... Droplets of water equal greatly reduced boiling point.....Doesnt water alone boil something like 212 degres<insert smart ass look on my face>. Thats actually the beauty of glycol, it absorbs the water, and spreads it so it doesnt boil as easily. As for those that dont belive you car needs a brake fluid flush on a regular basis.... great, come get your oil changes at my shop..... PLEASE.... I need the money that I will be getting when your master starts leaking from fried seals or the calipers freeze up from contamination, or the wheel cylinders blow soaking the shoes making for a complete rear overhaul..... All of which can be avoided by maintaining your fluid system. Glycol based brake fluid, added with silly hi temps, added to water/moisture= Acid build up....Acid build up equals blown parts.
Good stuff to know. Explains a lot of what I was wondering about this week. On my last run of the day at McGill last week my rear brake started to fade at the last 1/2 mile or so. The lever was going almost all the way down and soft. I know they get hot when I ride up, or should I say down, there.
Just to clarify, when you say "compress the caliper slowly", do you mean by squeezing the brake lever, or do you mean to push the piston back with the box wrench? Thanks!
This is a great thread. I am normally a DIY, but have never bled brakes, changed fork oil etc. What does it typically cost at a LBS to have these services done? Plus I would rather let them dispose of the old correctly etc..
I dont know of a shop that correctly disposes of any toxic things( trash cans work for them), sucks but true.
I mean the pushing back in of the pistons into the caliper. Also, when your done pushing fluid, and you have closed your bleed screw, make sure the pistons are still fully seated before you put the plug in the lever.
