I've already installed SS lines.... and played with pads.
The problem is in the master cylinder. (in order to change it - I have to calculate hydraulic ratio and get new MC)
And then in overheating brake rotors. Increasing diameter from 296 to 330 will solve it.
About expensive projects///
Emmm.... I want to use galfer brake rotors. 296mm costs as almost the same as for 330mm. =)
Also cbr600f4i and 954rr have the same pad. In case of Galfer - FD219.
as an example FD219G1370:
CB1300F Super Four (SC40) 2001-2002,
CB400SF Super Four Vtec NC39, NC42 1999-2013,
CBR600FS Sport 2002,
CBR900RR Fireblade 1998-1999,
CBR900RR (CBR929RR) Fireblade 2000-2001,
CBR954RR Fireblade 2002-2003,
GL1800C Gold Wing F6C Valkyrie 2014-2015,
How are you overheating the F4i rotors and how is it manifesting itself?
That asked in light of the F4i front brakes being pretty much the same as the 919s', aside from slightly different slave cylinder pistoning and having about 10% more brake pad area.
A good starting point for MC piston sizing for the 954 calipers would be the OEM sizing, that said on my assuming, correct or otherwise, that the 954 had a radial master.
My guess is that you will be totally on your own in having to design an adaptor bracket to correctly graft 954 calipers to the F4i fork legs, in both axial and radial terms.
I think it's safe to say that pretty much everyone, if not everyone, that has larger than OEM diameter rotors on their F4i, 599 or 919, will also have an USD fork conversion, with the USD conversion being the primary mod.