what brakes fit nc35?

[speedy231278]

So is 16mm the stock size Rick?

Thanks
Luke

5/8 stock on the SP1 and SOME CBR900s, and on the RC30.

i found through research that i wanted an exact same "LOOKING" master cylinder as the stock NC30 one, and found that a CBR900 1990model and the RC30 are the only ones that do and that offer a 5/8" its hard to locate one i took me over 2 months until VFRman steve came to my rescue

14mm is stock on the NC30

I've looked into this for a while, having a pair of 600rr3 calipers hanging about. my notes disagree with the figure given about for the SP1 m/c, but then I have frequently been known to be wrong in the past!

I've got the following so far:

SP1 3/4 (19mm)
SP2 11/16 (17.5mm)
900RR 92-95 9/16 (14mm)
919RR 96-99 5/8 (16mm)
929RR 00-01 3/4
954RR 02-03 11/16
1000RR 04-? 11/16
600RR 03-? 11/16

I think after 2004/5 or thereabouts the 600RR and Blade went to the radial caliper and MC setup, so I don't have figures for those, as I think that neither they nor the style of MC with the reservoir built in to it will fit on an NC35 due to clearance issues with the air tubes.

I find it interesting that the original Blades fitted with the same stock calipers as the NC35, but larger discs (?)****, had the same size MC, yet it appears that things vary with the gold ones. As best I can tell, the SP1/929RR and 600RR3 all have 34+32mm pistons, but the former use a larger MC than the latter. Is this due to the extra speed and weight of the SP1/929RR over the RR3? Later on, it appears that the calipers reduced in size to 32+30mm pistons for the SP2/954RR, with a smaller MC. Not sure yet what happened with the 600RR, but it went radial about the same time....

So, general consensus is that the best compromise between lever travel, outright stopping power and decent feedback is to use a 16mm MC with these calipers on an NC, rather than anything larger?

****edit: just found that Blades had the same 296mm discs until they went to 310 in 1998

[Neosophist]

So is 16mm the stock size Rick?

Thanks
Luke

5/8 stock on the SP1 and SOME CBR900s, and on the RC30.

i found through research that i wanted an exact same "LOOKING" master cylinder as the stock NC30 one, and found that a CBR900 1990model and the RC30 are the only ones that do and that offer a 5/8" its hard to locate one i took me over 2 months until VFRman steve came to my rescue

14mm is stock on the NC30

I've looked into this for a while, having a pair of 600rr3 calipers hanging about. my notes disagree with the figure given about for the SP1 m/c, but then I have frequently been known to be wrong in the past!

I've got the following so far:

SP1 3/4 (19mm)
SP2 11/16 (17.5mm)
900RR 92-95 9/16 (14mm)
919RR 96-99 5/8 (16mm)
929RR 00-01 3/4
954RR 02-03 11/16
1000RR 04-? 11/16
600RR 03-? 11/16

I think after 2004/5 or thereabouts the 600RR and Blade went to the radial caliper and MC setup, so I don't have figures for those, as I think that neither they nor the style of MC with the reservoir built in to it will fit on an NC35 due to clearance issues with the air tubes.

I find it interesting that the original Blades fitted with the same stock calipers as the NC35, but larger discs (?), had the same size MC, yet it appears that things vary with the gold ones. As best I can tell, the SP1/929RR and 600RR3 all have 34+32mm pistons, but the former use a larger MC than the latter. Is this due to the extra speed and weight of the SP1/929RR over the RR3? Later on, it appears that the calipers reduced in size to 32+30mm pistons for the SP2/954RR, with a smaller MC. Not sure yet what happened with the 600RR, but it went radial about the same time....

So, general consensus is that the best compromise between lever travel, outright stopping power and decent feedback is to use a 16mm MC with these calipers on an NC, rather than anything larger?

I read about the RR2/RR3 blades having a smaller MC.

Brake calipers (two front, one rear) feature Nimuflon™-coated steel pistons and Teflon-coated rollback seals to enhance braking feel under repeated hard use.
Brake fluid system pressure is increased 10 percent, resulting in even better braking feel and performance.

Not sure how they increased the pressure.. smaller diameter lines? Different caliper routing or something but a smaller MC was part of the package.

[speedy231278]

Reducing the size of the MC will increase pressure assuming the lever is unchanged. Plucking out silly figures to make the sums easy, if you apply 1KG of force to a master cylinder area of 1cm, then you will apply 1KG/cm to the pistons. If you reduce the diameter of the piston to 0.5cm, and apply the same force, you'll get 2KG/cm at the pistons. However, for the same distance of lever travel, you will displace half the amount of brake fluid, therefore the pistons will only travel half the amount. The size of the brake lines should be irrelevant, unless they are OEM rubber ones, in which case they will expand slightly, and absorb some of the effort of the master cylinder.

I guess the relationship between the master cylinder diameter, piston dimater and the lever travel is what affects the 'feel' of the brake lever. I guess if it's too small, the lever travels miles and you have to give a huge tug to get the brakes to do anything, and if it's too big, the slightest touch will have you doing a forward roll. Taking different bits of braking systems from various different bikes and putting them together on another must therefore require a little trial and error to find a solution that neither ends up with supposedly more powerful brakes being all pathetic and spongy, nor being like an on/off switch!

Standard NC35 calipers have 30 and 27mm leading and trailing pistons. My notes say that the SP1 and 929RR with 19mm MCs are 34+32, and it appears that RR3s were as well. Later 17mm MC equipped bikes had 32+30mm pistons.

Something else I've just turned up is the brake disc thickness. The SP1 (and presumably other bikes with the same calipers?) is stated as being a 5mm disc. SP2 is 4.5mm, as is stock NC35 I believe. Would this difference be an issue. In theory that's 0.25mm extra travel for each piston, which I guess is a lot less than the difference between the unused travel when the discs and pads are worn to the limit, and the point where the piston would travel beyond the edge of the fluid seal?

[Neosophist]

In theory that's 0.25mm extra travel for each piston, which I guess is a lot less than the difference between the unused travel when the discs and pads are worn to the limit, and the point where the piston would travel beyond the edge of the fluid seal?

The pistons don't retract after you release the lever.. they stay out and the pressure drops off, which is why disc brakes always bind very very slightly.

So the thinner disc wont make any difference as the pistons will come out until they make contact. (this is why your fluid level drops as the pistons come out more as the pads / disc wear)

The pistons cant come out as they will hit each other, and with brake pads / discs in the way too its impossible for the pistons to come out, even no disc and just the metal backing of the pads.

[speedy231278]

I didn't mean come out completely, just come out far enough that the back of the piston travels past the fluid seal, causing the caliper to leak. I would imagine that there's plenty of distance going spare to avoid that happening in the first place though.

[Neosophist]

I didn't mean come out completely, just come out far enough that the back of the piston travels past the fluid seal, causing the caliper to leak. I would imagine that there's plenty of distance going spare to avoid that happening in the first place though.

yep.. thats what I meant, its impossible to do that under normal cirumstnaces.

even trying to get the pistons out with an airgun they often hit each other (without pads!) and nothing leaks...

[porndoguk]

So is 16mm the stock size Rick?

Thanks
Luke

5/8 stock on the SP1 and SOME CBR900s, and on the RC30.

i found through research that i wanted an exact same "LOOKING" master cylinder as the stock NC30 one, and found that a CBR900 1990model and the RC30 are the only ones that do and that offer a 5/8" its hard to locate one i took me over 2 months until VFRman steve came to my rescue

14mm is stock on the NC30

The CBR900 (fireblade) wasn't made until 1992.

Perhaps the 1992 model if this is the right bike?

I'm a little vague on it to be honest I just went on a hunt after Rick O said that the RC30 and the 90s CBR900 fire blade master cylinders were the same part number and same "look" as the nc30, but the size of the MC was bigger obviously.

Edit:

My bad just reread his email

"Hi, Ricky -

What you need is not hard to find - it`s the master cylinder which was
used on the RC30 and early model Fireblades.

It looks identical to the NC30 one but where the NC30 cylinder has
`14` (mm, that is)cast into the surface nearest the handlebar, the one
you need has `5/8` (inches)."

I just assumed the blade was a 90s bike

[Neosophist]

Ah that will be the 92 blade then, did you get your MC sorted because I think I have a 92 blade MC knocking around..

[speedy231278]

Would be interesting to know what size it is, everything I've found so far for the Blade says 14mm (9/16) for 1992-1997. Wouldn't be the first time the aftermarket people got something wrong.....

[CMSMJ1]

What size is the RVF? 14mm? or 5/8?