I thought the stock reservoir was alloy. Try treating it with paint stripper then polishing it.
Sorry Rob, my post is a bit misleading.
Basically I'd like to do some sort of brake upgrade and someone told me that the round fluid reservoirs give better braking. I don't know how or why and I'm still a n00b so I'll believe anything
Fluid resevoirs don't have any effect on the brakes. It's the master cylinder that matters. On your bike the reservoir and master cylinder are integral. A lot of high performance cylinders actually have remote reservoirs - usually of clear plastic. The cylinder has to be matched to the calipers though. There is a fashion for so called radial cylinders, which might be what you're thinking of, but they don't really make much difference to brake performance, and any change of cylinder can make the brakes a lot worse if it isn't matched to the calipers. What matters is how much fluid the same lever movement displaces, and that's a function of the internal piston size.
A big master cylinder piston needs less lever movement and will feel firmer, but needs more pressure on it to give best braking effort. A small clinder needs a lot less effort, but at the expense or longer lever movement and the possibility that it might feel a bit spongy.
You'll get the best improvement on your brakes from a change of pads, and another popular upgrade, although it doesn't make a lot of real difference, is the fitting of braided brake lines.
You can feel the difference on a bike with ABS because the lines are really long, but on a modern bike with fairly short lines you shouldn't feel much difference between stock and braided lines unless the stock lines are getting a bit old.
And where you can feel the difference, it's only a difference in feel, not in actual brakling performance, although the feel is important to rider perception.
I am a big fan of the zx6r master cylinder over the 650's oem version, much better throw in my opinion, seems a bit more quality too.
** that said, you will need to find a solution for mounting the reservoir if you do go that route. The zx6r uses it's handle bars to mount the reseviore. I tried to fashion an aluminum bracket to fit through the two bolts which secured a clip on and then bend it at such an angle that it would support the reservoir, unfortunately I didnt have hard enough aluminum or good enough tollerances starting off in fabrication to make it work.
Last edited by 650samurai; 04-27-2012 at 03:12 AM.