Mr Riggs Hydraulic Clutch Conversion

I've been wanting to machine a clutch slave cylinder for some time. After much googling I gather a 13mm master cylinder coupled to a 25mm slave cylinder should work. Now being a lover of all things mechanical looking, I was going to machine one up so it fit on the outside of the left side cover, purely for looks The machining is easy, the problem being the seals inside the slave. I've no idea where to get thee seals from in Oz. Things are different here, trying to get anything out of the ordinary is just impossible.
Have you considered some sort of automotive brake slave cylinder as the source of pucks and seals? Surely there is one that would work.
 
Have you considered some sort of automotive brake slave cylinder as the source of pucks and seals? Surely there is one that would work.

It's not the pucks or seals that Riggs discovered issue with, it was the odd contours of the seal grooves. He assumed that a standard o-ring groove would be sufficient and discovered that they're tapered. He wasn't able to get them to seal properly.
 
It's not the pucks or seals that Riggs discovered issue with, it was the odd contours of the seal grooves. He assumed that a standard o-ring groove would be sufficient and discovered that they're tapered. He wasn't able to get them to seal properly.

Bingo!

I found that the oil seal groove was tapered to exert more pressure on the entrance to the bore.

As soon as this was addressed, no loss of fluid.
 
Last edited:
Businesses open up today after the Xmas break, so .I'm off to a Hydraulic shop this afternoon to see if they have any seals that will fit.
 
It's not the pucks or seals that Riggs discovered issue with, it was the odd contours of the seal grooves. He assumed that a standard o-ring groove would be sufficient and discovered that they're tapered. He wasn't able to get them to seal properly.
The pucks in wheel cylinders are tapered. When pressure is applied it spreads the seal preventing any leaks.
 
Might have had some luck, I ordered a 25mm pressure seal and dust seal from a hydraulic shop this afternoon, expect to pick them up tomorrow. I asked for non tapered seals if possible. I notice the seals in the brake callipers aren't tapered, so as long as I get the seal groove smooth enough and the right depth, the seal should do it's job. I'll find out over the coming week I suppose. Expecting to fill my crap bin with failed experiments.
I'll be making the body from 6061, or 7000 series, whatever I have to hand, and thinking of uing either brass or bronze for the piston.
 
Is there anyone using the xs650.de clutch slave hydraulic, and can tell me about how good it works?
Also, sharing some photos would be cool.
I am in the market for a hydraulic clutch, but would love to have one inside the case.
On the topics that i have found on this website, nobody said anything about how its lasted.

Link to the part at xs650.de: https://www.xs650shop.de/en/crankcase/1557/clutch-slave-hydraulic-70-84

I am currently gathering parts for my build.

Thanks in advanced.
 
I have one, and as expected with German engineering, its excellent. I purchased the unit including the optional hydraulic line and master cylinder. My only criticism is the hydraulic line connection to the slave cylinder - didn't like it. An easy re-arrangement with a banjo bolt and standard styled hydraulic line length to suit my riding setup.

I recommend the unit and I know they sell well. I missed out when I originally ordered one and had to wait for the next production batch.
 
I have one, and as expected with German engineering, its excellent. I purchased the unit including the optional hydraulic line and master cylinder. My only criticism is the hydraulic line connection to the slave cylinder - didn't like it. An easy re-arrangement with a banjo bolt and standard styled hydraulic line length to suit my riding setup.

I recommend the unit and I know they sell well. I missed out when I originally ordered one and had to wait for the next production batch.
How do you find shifting gears with the setup? I haven't had my bike running yet but with the setup, HD springs, I find I can't change gears by spinning the wheels off the ground. Measuring the clutch plate travel gets me about 1.3mm which I thought was a bit low. I think there is probably about 1.4mm-1.5mm of movement on the slave cylinder itself. I was thinking of going up to a 14mm master from the given 12.7mm
 
Back
Top