Problem with bleeding front brakes

[maverick57]

Hi all, hope someone can help. I recently bought my 1995 GSX750F and on the ride home I noticed the front brakes very spongy. I stopped into my local bike shop and explained what was going on and he told me that the front brake pads were probably worn so I bought a new set. I also bought a master cylinder rebuild kit just in case. Now after rebuilding the master cylinder and replacing the pads i went on to bleed the brakes. For some unknown reason I cannot get the callipers to push the pads onto the disc. I spent ages bleeding the air out and I don't think there is any more in there but I still have no front brakes. The callipers worked before but brakes were spongy. please does anyone have any ideas I can try??

[gwigs]

Try clamping off the brake hoses just above the callipers,if the brakes dont feel spongy its probably the calliper seals.I have just had the same problem and have ordered new seals and I,m pretty confident that it will fix the problem.

[maverick57]

Thank you gwigs...I just went out and did what you suggested and bingo...no spongyness. Will order new seals now..Thanks so much, will keep that in mind for future reference...

[scottynoface]

Try clamping off the brake hoses just above the callipers,if the brakes dont feel spongy its probably the calliper seals.I have just had the same problem and have ordered new seals and I,m pretty confident that it will fix the problem.

I had a damaged bleeder screw on one of my calipers as well, same issue.

[jarvis]

One trick I learned was/is to pull front brake on over night, use bungy cord to keep leaver back (or stand there all night, your choice) and see how it feels in the morning.

[maverick57]

Thanks guys, I will check what you have mentioned, and thanks...

[rexazz2]

beware of the position of the master when bleeding
I either try level or lever end slightly higher in case air is getting trapped in the master bore
they move so little fluid that a little air can cause an issue

I have a mighty vac bleeder and it works awesome IMO

[gwigs]

Thank you gwigs...I just went out and did what you suggested and bingo...no spongyness. Will order new seals now..Thanks so much, will keep that in mind for future reference...

I think I spoke too soon,put new seals in the callipers this morning but still cant get decent pressure,spent the best part of 6 hours and got nowhere.
If I clamp of just 1 calliper it gives good pressure,doesn,t matter which calliper I clamp off,it makes a big improvement.
I,m pretty frustrated by it ,Ive bled brakes many times before and never had a problems,I,d be ripping my hair out if I had any....

[gwigs]

Think I have my problem solved,some how put callipers on wrong sides last time I had them off,
the hoses need to come into the callipers from the bottom so that the bleed niples are higher
so as not to trap air.....will find out soon wont take long to swap em over.....
Found this out by googling it ......love the interweb....
Will keep you posted.

Think I have my problem solved,some how put callipers on wrong sides last time I had them off,
the hoses need to come into the callipers from the bottom so that the bleed niples are higher
so as not to trap air.....will find out soon wont take long to swap em over.....
Found this out by googling it ......love the interweb....
Will keep you posted.

Nope that was wrong they on go on one side, bollocks back never ending bleeding

[indianboy7]

I have used this method in the past with good results......

reverse bleeding

[gwigs]

Think I have my problem solved,some how put callipers on wrong sides last time I had them off,
the hoses need to come into the callipers from the bottom so that the bleed niples are higher
so as not to trap air.....will find out soon wont take long to swap em over.....
Found this out by googling it ......love the interweb....
Will keep you posted.

Nope that was wrong they on go on one side, bollocks, back to never ending bleeding

[jarvis]

Are you bleeding them with a piece of tubing into a container of fluid leaving the nipple fully open while you pump the lever?

[gwigs]

Are you bleeding them with a piece of tubing into a container of fluid leaving the nipple fully open while you pump the lever?

Yes thats the way I normally bleed them but I have tried a bleeder with non return valve as well as bleeding with a syringe .

[jarvis]

Yes thats the way I normally bleed them but I have tried a bleeder with non return valve as well as bleeding with a syringe .

Still no luck I take it?

If you haven't done already I'd be inclined to start from the beginning, check everything is tight, all the crush washers are in place then top up with fluid and start pumping.

Failing that a set the bloody thing on fire and claim off your insurance lol

[drvk]

Yes thats the way I normally bleed them but I have tried a bleeder with non return valve as well as bleeding with a syringe .

Have you open master cylinder n clean it ? Maybe need to clean the whole brake lines.