I have trawled the net for hours trying to find an answer to this one with ZERO success Hopefully someone on here much much cleverer (Is that an actually a word ) than me might be able to answer this and help me out . What effect does increasing the bore size of the clutch master cylinder have ? I.e if I go from a 12.7mm Dia bore to a 16mm Dia bore. Will the clutch become lighter to use ?
A bigger bore will move more fluid but will be harder to pull, a smaller bore will move less but be easier to pull, problem with a clutch slave is you need to move enough fluid to move the piston far enough to disengage the clutch, a small piston size is easy to pull but often does not displace enough fluid to fully disengage the clutch. Note, the fulcrum or pivot point of the lever has a role to play in how easy the clutch is to pull too, you could run a bigger piston with a better action.
Cheers Arthur. Thinking of getting the Brembo 16RCS so mc piston has increased from 12.7 to 16 but hopefully with 2 different ratios I can find something to suit.
The 2nd factor besides piston diameter is the distance from pivot centre to the load point (plunger) the smaller that distance is the lighter the lever will feel but it will also use more travel to achieve the same piston movement. We sell more short travel i.e. 16 x 18 cylinders to race users where the clutch is not used as much, road users tend to go for a lighter feel i.e. 16 x 16. Adjustable ratio cylinders are great but you will probably only adjust it once and then leave it on your favourite setting, try & find a similar bike with one fitted & try it for feel. A 16 x 16 or 16 x 18 fixed ratio will save you a few bob. We can do you a good deal on Accossato cylinders, adjustable or fixed ratio. Give me a call if you want to go through the options in detail.
