Anyone know whats happening here?

[Zephyr_Pete]

Hi Guys,

Appologies for the long winded post.

A while back I fitted new front pads to my zephyr 750, immediately after there was significantly more travel in the front lever, to the point where it can almost come back to the grip.

Since then I have fitted a new master cylinder seal kit, new piston seals, freed up the slides and blead the system many times with new fluid (The main Kawasaki dealer has also had a go). All this has had absoloubtly no effect.

Today I bought some brake cleaner and freed up the bobbins as best I could whilst still on the bike, by spinning with an M8 nut and bolt method gently nipped up. This also had no effect, but admitedly the bobbins were pretty siezed before this.

All I could think is that air must still be trapped in the lines somewhere. So I decided to clamp the hoses just below the splitter to try and eliminate where the problem is coming from.
The odd thing was I clamped the left hose and the lever felt perfect and back to normal, so i thought the problem must be something to do with the right caliper. I then removed the clamp and clamped the right hose, again the lever felt perfect as it used to be.



I then completely removed the clamp and the lever went back to being spongy. This one has got me beat, and any help on what going on would be much apreciated.

[newnut]

get some steel braided hoses. should fix it, maybe your lines are perished.

[CBRowner]

Sounds like air in the brakes but you've had them bled a few times now :-?

Have you checked the lever? There could be something going on in that area.

Apart from stripping it all down again, I can't think of what else it could be especially as a main dealer can't do anything

[Zephyr_Pete]

I think braded hoses will be my next try. The main dealers solution was to fit new discs at £170 each, as mine are aparantly slightly warped. This seemed a little drastic as the problem only occured after fitting new pads, and I want to be sure ive tried everything else first before I concider spending that sort of money.

[CBRowner]

I've heard of this problem happening before but I've so far never suffered from it, although I need to replace my pads soon but I have a few months of braking left in them.

Hopefully you get it sorted soon [smiley=thumbsup.gif]

[CBRowner]

I just thought, have you tried moving the clamps around to find if it's a problem along the pipes?

It may be worth starting from the bottom and clamping it avery inch or so until it becomes spongey or not, that way you'll know if it's your pipes [smiley=thumbsup.gif]

[Zephyr_Pete]

Good shout, i'l give that a go. Braided lines seem the way forward to me, even if thats not the problem.

[CBRowner]

Another option would be to put the pipe, at regular intervals, into some water to see if there's any bubbles. You could also do that with your caliper just to make sure that the problems not coming from there [smiley=thumbsup.gif]

[Zephyr_Pete]

Just tried to pinpoint the problem area further. I started by clamping the bottom of each hose individually where it meets the calliper. Still get a firm leaver, same as clamping the top.



Seems as if the 2 calipers work fine individually when isolated, but dont seem to be sychronised and work together to give a firm lever.

[newnut]

have you checked to see if any of the pistons are leaking fluid? they are like your front forks, pitting, scoring or knackered seals will cause your problem, especially after changing pads as you've moved the pistons back further than they have been for a while. braided lines always help firm up your brakes. take the calipers off you need to check for any leaking fluid, give them a good service while they are off. brake cleaner etc. hope that helps.