[samuelmi]

Recently bought a ZX10R in immaculate condition, but it had been sitting for a long time.

Rear brake was seized but worked after a bleed.

Have been pumping and trying different methods to get the front brake working for 2 days now, nothing works.

Front brake works after several pumps and becomes solid. After moving the bike back and forward it goes back to requiring several pumps, moving the bike side to side has no effect on losing the pressure. When I leave the bike on the side stand, it builds pressure but when I move it forward it instantly loses pressure.

When I bleed from the calipers there are no bubbles, only clear fluid. When I bleed from the Master Cylinder sometimes I get huge streams of bubbles but I have done this for 2 days now and its not stopping. There are no leaks of fluid, can air seep into the master cylinder without fluid seeping out?

 

[samuelmi]

Recently bought a ZX10R in immaculate condition, but it had been sitting for a long time.

Rear brake was seized but worked after a bleed.

Have been pumping and trying different methods to get the front brake working for 2 days now, nothing works.

Front brake works after several pumps and becomes solid. After moving the bike back and forward it goes back to requiring several pumps, moving the bike side to side has no effect on losing the pressure. When I leave the bike on the side stand, it builds pressure but when I move it forward it instantly loses pressure.

When I bleed from the calipers there are no bubbles, only clear fluid. When I bleed from the Master Cylinder sometimes I get huge streams of bubbles but I have done this for 2 days now and its not stopping. There are no leaks of fluid, can air seep into the master cylinder without fluid seeping out?

By not stopping i mean the problem with the pressure. the bubbles stop

 

[alexei]

hello and welcome. Is this your first forum?

 

[samuelmi]

hello and welcome. Is this your first forum?

Hi, yes its my first forum.

 

[samuelmi]

When pushing the bike slowly there is a slight ticking noise every rotation, rotors no longer straight?

 

[scout]

what bike as in year; miles on it. Bike appears parked outside. Are you located in S. Korea? Ask, as know the weather of hard there. Don't ride it until you sort the brakes.

 

[don sholand]

Try taking the MC off the bars, turn it upside down and shake it, tap on it, etc, could be some trapped bubbles in there.
also, zip tie the front brake lever full back to the throttle grip overnight.

the “huge streams of bubbles” sound like maybe a leak where your clear bleed tube goes over the metal nipple. Make sure that seal is air tight.

are the brake lines stock or stainless steel aftermarket? If have been changed, and there is a “T” fitting in the front lines, take that off and turn it upside down and tap on it.

somehow there is still air in your system.

 

[samuelmi]

what bike as in year; miles on it. Bike appears parked outside. Are you located in S. Korea? Ask, as know the weather of hard there. Don't ride it until you sort the brakes.

2013, 66000KM. Bike was parked outside in Dubai for a few weeks by the last owner and indoors by the previous owner apparently, assume moisture has got in.

 

[samuelmi]

Try taking the MC off the bars, turn it upside down and shake it, tap on it, etc, could be some trapped bubbles in there.
also, zip tie the front brake lever full back to the throttle grip overnight.

the “huge streams of bubbles” sound like maybe a leak where your clear bleed tube goes over the metal nipple. Make sure that seal is air tight.

are the brake lines stock or stainless steel aftermarket? If have been changed, and there is a “T” fitting in the front lines, take that off and turn it upside down and tap on it.

somehow there is still air in your system.

I have tried all of this, but thanks!

I believe the brake lines are stock.

I am thinking its got something to do with a bent rotor, its not visible, when I push the bike over a certain point it clicks, all the brake pressure disappears, I pull it in to create pressure and push/pull it back and again it clicks and disappears. At all other points throughout the rotation of the wheel it keeps pressure. But its weird, it makes such a dramatic difference to the pressure yet there is no visible difference in either of the rotors (its not spongy, its none existent, the lever goes all the way to the bar and requires 2 squeezes to become spongy, and 3-4 to become hard).

I got some new rotors on order which should arrive in 2 weeks, so will keep updated.

 

[alexei]

ABS model?

 

[samuelmi]

ABS model?

Yes

 

[Porschenut]

Whatever the problem with the rotor may be, the constant stream of air from the master cylinder is a 100% sign that you have a different problem. You can check your rotor with a straight edged implement to see if it's warped. Try to see if you can get a refund on the rotors until you know for sure. They're expensive and the cheaper aftermarket rotors like EBC apparently aren't very good.

 

[alexei]

trace the hose, find the ABS pump and check for leaks there too
service the MC if possible
the 'click' that you heard, could be from a faulty ABS pump?