Hi Herb, thanks for the suggestion. I have thought about using a car master cylinder, the thing that is stopping me is the pipework. A car uses different pipes and connectors than a bike system so I would have to get some special pipes made.. At a cost! I could cobble something together using both car and bike bit's, but brakes shouldn't been bodged together..
Says a chap who is mixing front and back bike bits together
Howdo Richard, I think you have hit the nail on the head (much better than hitting your finger) there with the "system fluid volume" bit.
After today's "sort the brakes" session I'm getting the feeling that the master cylinders simply don't have the capacity (or push) for getting enough pressure up to push the pistons in two calipers..
Don't worry about flying spanners.. I'd only end up throwing the ones I'm using at the time, and would have to search to find them again!!
But I'm sure I have some empty coffee mate tins I can chuck at you
Hey Callen. I did try something very similar to what you suggest today. Rather than shim between the pads and pistons, I took the calipers away from the discs, pushed the piston fully in, and placed some nice thick spanners between the pads.. With two calipers plumbed in, despite a huge amount of bleeding I still could not stop the master cylinders from bottoming out!!
So what have I been up to in the Shack today? Well most of it was spent bringing my Raider 10 out of hibernation (I can't remember if I've used it this year) to be put on grass cutting duties..
With a sharpened blades it cuts very well
Of course While in the shack I could not resist having a fiddle with the brakes.
Out of interest I thought I would play with the plumbing one side..Still two calipers but each one with their own master cylinder..
20 min's later after making sure every last bubble of air was out of the systems, I had two master cylinders that no longer bottomed out!!
I need to do another little test drive tomorrow with changed tire pressures, but things are looking good
To me, the fact that no matter what I tried I could not stop the cylinders bottoming out with 2 calipers attached, but could with only the 1 caliper, tells me that the cylinders are not big enough to flow the fluid to 2 calipers!!
So... I've just been on Fleabay and bought a couple of Honda Fireblade rear master cylinders with a whopping 5/8" bore. Hopefully they should be up to the job