put on a new back tire and now the back brakes dont work well i didnt open the brake system just unbolted and pulled the brakes up and then took off the tire it has a hard pedal when you push on it just no stopping power clean off the rotor with brake cleaner
wipe the pads and cleaner them still no brakes what did i do wrong ?? its a 09 s/g

 

Pump it a few times until it pumps back up. If that does not work we will have to investigate further.

Drew

 

pumped up the pedal no change was working fine until i put it back together. i was thinking it may have got some grease on the rotor but that didnt pan out to be the case i was thinking i might need to bleed the lines but if i didnt undo any line i shouldnt have to do that i was thinking maybe i am wrong

 

Whenever you pull off a caliper, typically, you will push the piston back a bit to make it easier to R&R. This drives crap back into the system assuming there is some in there, usually there is. This may have caused a bit of debris to clog up the vent hole in the master. You should definitely bleed the brake line. If it doesn't want to bleed real well and never pumps up, that vent &/or something else might be amiss.

Let the bleedin begin.................

 

If the pedal is firm you should not have to bleed the brakes. Push the pedal by hand and see if you can see the pads moving.

 

Re-clean with brake cleaner and put a few miles on the bike, it should improve. You probably just got some oil or grease on the system.

Mike

 

thanks guys i cleaned the pads and rotor again and checked the pads for movement which they will move bleeding the brake line again and now its somewhat better i drove it some i still dont think its 100% right its the wife bike she said it better now after she drove it it does seem to stop better

 

There is no need to bleed the brakes if you did not loosen the line THE ONLY WAY FOR AIR TO ENTER IS A LOOSE FITTING IT CANNOT GET IN THROUGH THE PSITON then there is no air is in the system you only need to bleed the system to get air out. What happened is when you spread the psitons open to remove the caliper they moved in past the dirt line where they normally stop and picked up all the road grime now they are not moving free and even.
what you need to do is remove the caliper and the pads hold in in your hand with rubber gloves on and use brake cleaner and a small pick like a plastic dental pick and a tooth brush clean between the piston and the caliper housing you'll be amazed how much crap will come out of there do this every tire change front and rear and you brakes will perform like new.

 

What he said. I always open the bleeder on the caliper to push the pistons back in because it forces the heat worn fluid and any contaminants in the system out instead of back into the system. Then once that is done I clean around the piston with brakleen & a dental pic like stated above. Then re-assemble & bleed and then spray off the whole caliper assembly with brake kleen and zama: New brakes.

 

hey thanks for the info wayne