need help with disk brake
 

Went to a cheap bike shop and told them that my disk brake was making a slight noise. they put some oil on the disk and the brake seized to work. it made loads of noise. i took it home and cleaned as much of the oil as i could from the out side. i put some WD-40. b4 the bike would almost flip if i slammed the brake. now take like10 secs to stop from high speed with front brake

back brakes are fine

bump

sounds like contaminated pads. you can try cleaning it one more time with rubbing alcohol, if that does not do it, then its likely time to change those pads and then clean the disc one more time with rubbing alcohol before using.

Oil and disc rotors do not mix. Your pads are now likely fatally impregnated with oil. Step one- get new pads. Step two- clean the rotors with alcohol. Step three- find appropriate set-up instructions for your model of brake.

ok oil doesnt work, wat about wd-40

A cheap bike shop? Was this a real bike shop or your next door neighbor who knows nothing about bikes, or brakes for that matter? Putting oil on the disc ruined your brake pads. You need new ones. Most disc brake issues are due to the adjustment of the caliper on the fork or the adjustment of the pads with respect to the rotor. If you don't feel comfortable making these adjustments yourself, take the bike to a real bike shop and let them do it. It's not rocket science but it does take some skill and the correct tools.

A BIKE SHOP put OIL on disc brakes?

No matter how cheap a shop they are, they should be smarter than that..

Sounds like your "cheap bike shop" owes you a new set of pads. Make sure they are the same brand as the brakes, and not "cheap replacement pads."

thanks for the feedback. i found another bike shop where u can actually replace the pads. i also went the place where i bought it from. they change the whole brake for a pretty cheap price. i live in dubai, UAE, so over here if u don't go to specified places then you get bike shops who bought a set of tools and some bikes, with universal parts.

When you say slight noise.... do you mean under braking, or when you are not breaking and underway?

It matters with a cheap bike.

no you don't want to put wd-40 on brakes.

At first I thought you were making this up. Maybe they thought it was like the Shimano Roller Brakes, those get greased,

The thing is, with lower end cable disc brakes... the fixed pad should be set so that it is just touching the rotor... you should hear a slight scraping noise as you turn the wheel. The adjustable pad should then be set as per your preference. Some may like a long lever pull, some may want on/off brakes.

The OP has not specified just what level of kit he has, nor if this is happening under braking? All this may have needed was a small backing off of the fixed pad, no need for oils.

If this is set wrong it will cause the calipers to flex the rotor, and this could also make them squeal under braking, the fixed pad supports the rotor and prevent it from flexing because it is just touching it.

BikeLikeMad, get new pads (your idiot-staffed shop owes you a set) and install them yourself so they're done right.

Find the manual for your brakes -- it's surely posted online -- and cross-check with the instructions at Park Tool's website:
http://www.parktool.com/repair/byregion.asp?catid=14