955 to 675 master cylinder conversion!

[Owl]

Doesn't the 675 run Nissin radial calipers?

I've noticed the 955 doesn't....therin probably lies the problem. Pretty hard for a master to cause fade, and by changing it you're only masking the problem, you'll still get fade, you just move more fluid so it isn't as noticeable. I'd be looking to see if any other calipers will fit (gsxr,r6 or suthin else that does work) rather than the master.

The early ZX10's had the same issue, and many 'fixed' it with a different master/braided lines/flash brake pads etc, but the real problem was the caliper, which when changed transforms the brakes like you wouldn't believe.

Of course I could be completely wrong

No, you're sort of on the money! Oh and my calipers are Nissin radials.

Issue does lie within the calipers, specifically the pistons, though I'm not experiencing fade. The issue I have is longer lever travel than I'd like, but still plenty of bite. Cleaning and freeing up the pistons regularly solves the problem, but I thought the larger M/C would make it firmer for longer. It has, but at the expense of feel.

I'll stick with this setup until after I replace my pads and then I'll reassess it. I may end up going back to my OEM M/C and cleaning more often.

05-06 GSXR1000 Tokico's are a direct fit and apparently much better, but then I'd need new lines and caliper bolts to go with them. Plenty of options though!

[DEATH_INC.]

No, you're sort of on the money! Oh and my calipers are Nissin radials.

Issue does lie within the calipers, specifically the pistons, though I'm not experiencing fade. The issue I have is longer lever travel than I'd like, but still plenty of bite. Cleaning and freeing up the pistons regularly solves the problem, but I thought the larger M/C would make it firmer for longer. It has, but at the expense of feel.

I'll stick with this setup until after I replace my pads and then I'll reassess it. I may end up going back to my OEM M/C and cleaning more often.

05-06 GSXR1000 Tokico's are a direct fit and apparently much better, but then I'd need new lines to go with them. Plenty of options though!

Now this I find very interesting....the supposed ultimate upgrade on the 10 is....ZX14 NISSIN calipers. Tho a lot of us are running the CBR thou Tokico's, which offer more feel and still lotsa stopping power.
Interesting about the pistons, I tried some gsxr calipers on my ZX10, way better than the stockers, and identical externally, except for the pistons. The Gixxer has thick ally pistons, the ZX10 has thin stainless ones, which I believe flex and transfer too much heat. The 04-07 ZX10's use these calipers, and both suffer from excessive lever travel and fading. Both the gixxer and 10 use Tokico's.
I wonder if yours has a similar fault?

[Owl]

I wonder if yours has a similar fault?

I may be able to shed some light?

My OEM calipers had a fault and while recognised worldwide, not by Triumph NZ (long story). They were fitted with stainless pistons (not flimsy), but they'd accumulate crap, stick and lose lever firmness. Cleaning and massaging them would make them like new for about 3000km.

I replaced my calipers with the 07 Speed Triple Nissins, which came with the "fix", being coated pistons and of a slightly different shape. They work better for longer and last about 7000km before they require cleaning. Even at their worst, they're still not as bad as the OEM shiny pistons.