I have a 954 and it seems to be having some brake problems, it has braided steel brake lines all connections seem fine. There is only 1/2 inch play in the lever, I can bleed the brakes and that fixes it for a couple of seconds once I tighten the bleeder if I press the lever repeatedly it gets shorter and shorter back to the 1/2 inch. when the brake is applied it slows down but very slowly, ineffectively slow at that. any ideas?

Thanks for the help in advance.

so DID you put new brake fluid and then bleed them again. If so it might be the brake line how old or new is it?

Ive done it 4 times three with old fluid once with new and the same thing happens every time. and idk how old the line is it was on the bike when i bought it. It looks to be in good shape.

I would strip the master and caliper and throughly clean everything.
The rear brake is always going to be ineffectively slow on a sportsbike unless you significantly alter the weight distribution, it really is not designed to slow the bike down, that's the job of the front brakes.

ok and I know but whats the point of having a rear break if it does nothing?

It does help stop. I think its like 70% front 30 in the back or something like that.

It's a legal requirement to have two seperate braking systems on the bike, even if physics dictates that one is ineffective anyway.

If u really wanted to, U can actually take one rotor off the front and it will still be effective! But i wouldnt try it, becasue if that was the case why put two right

Nope.
There is no rule that covers all motorcycle designs or braking situations. Under emergency braking you should be 100% on the front tyre of a sportsbike for maximum stopping grip on the road. Using the front and rear at 70/30 is only going to stop you at 70% of your actual stopping ability.
If you can stop faster using both brakes then you need a lot more practise on the front brake.

TRUE! I was just passing what they tried to teach me in the motorcycle class.

Yes, I've done this myself.
The reason you have two big front discs is because the front tyre is the one that is going to stop your bike. You could use a single larger and heavier disc if you prefer, but you'll need a much larger wheel diameter to be able to fit a caliper around it and still provide effective leverage and pad area.
Using a single disc that is designed as one of a pair merely reduces the effectiveness significantly under hard usage.

Ok now that we understand Laws and regulations anyone else have any ideas lol

You have air or moisture in the system that you need to clean out.

nothing is helping, completely took the caliper apart and cleaned it and nothing, the master cylinder seems to be fine Im pretty sure its the piston or the piston seal does this make sense?

You haven't cleaned the master cylinder yet though?
You will be able to make the brake system work, but you won't make it able to significantly slow the bike down.
I did the rear brakes on one of my bikes a couple of weeks back and the piston was seized solid. I had to drift it out with a hammer. But it cleaned up and works just fine.