Why Have Dual Circuit Brakes

Good lady drives along the road brakes working with no problem.Going down a hill and a large bird walks across the road puts brakes on and they fail with no foot brake at all. Right to the floor and no stopping at all not like its 25% or 30%.

I drive it home, 5 mph with the handbrake and find the offside steel pipe where it meets the flexi pipe above the offside hub has a hole in it that the fluid is blowing out when I refilled with brake fluid.

So there are separate feeds from the master cylinder to the ABS unit and from the ABS unit it feeds one pipe to the back and they are common on the one pipe, one pipe to the front nearside brake and another to the front offside brake.

I'm I being thick here in thinking that one of the front brakes should have worked due to the dual circuits. As it did not give some braking what help are dual circuit brakes!

Well yes if there were enough fluid left in the system!

mickt wrote: Well yes if there were enough fluid left in the system!

Therefore why go to the bother of having a dual circuit master cylinder when the design of the system allows one leaking side of the master cylinder to empty the other working circuit. That's what I cannot get my head around.

A phone call to Suzuki is in order I think.

I'm not sure on the abs (I'll have to check the manual) but on the older models the brake circuit was spilt front and rear, if you had a leak like yours the rears should still work but you'd lose both fronts or vice versa if you had a leak on the rear. Now another thing I'm not sure on is if you had a single shot at it, ie if you kept repeatedly pressing the brake pedal it all goes whereas if you pressed the pedal once or twice you'd still stop albeit with reduced efficiency. I'll take a look at the book tomorrow to see if I can shed some more light on it.

Its a tandem master cylinder so you have to push it pretty much to the floor but you should still get some breaking.

It went straight to the floor and nothing at all braking wise.