long travel front brake lever

[nastyjones]

I bought this master cylinder for my gs 1100 that has a gsxr front end & a single disk. I am using a 2 piece brake hose. The brake lever travels almost to the grip before the brake grabs. I have bleed the crap out of the system & am pretty confident there is no air in the system. I have put up with this for 6 months.

What should I do next?

http://www.ebay.com/itm/FRONT-BRAKE-MASTER-CYLINDER-SUZUKI-GN125-GN250-GS250-/310706993330?pt=Motorcycles_Parts_Accessories&hash=item48579478b2&vxp=mtr

[Agemax]

the piston bore diameter is too small to move the pistons in the caliper

[nastyjones]

It has a 12.7 mm bore. What size would I need for a single disc?

[Agemax]

what GSXR caliper are you using? a 4 pot or 6 pot? the GN250 etc that the m/c was designed for only has one piston. you are trying to move enough fluid to push 4 pistons, (or 6).
you say you have a 2 piece hose, is it stock rubber or stainless lines?

[nastyjones]

4 pistons, stock rubber hoses. So how about this one? The bore is 14 mm.

http://www.ebay.com/itm/New-Front-Hydraulic-Brake-Master-Cylinder-for-Suzuki-GS750-GS1000-GS1150-GS1100-/271235656399?pt=Motorcycles_Parts_Accessories&hash=item3f26e7aacf&vxp=mtr

[Agemax]

try fitting a stainless hose, before buying another m/c, it should help a lot plus its a good upgrade to have anyway

[nastyjones]

Ok, so I installed brand new braided steel lines today & the front brakes are the same, still a long lever travel before any braking. It leads me to believe Agemax is right, the bore in the master is too small to move 4 pistons. Looks like I'll be upgrading to a 14 mm bore master from a larger bike.