Going to TRY and make a clutch slave cylinder

[great white]

My clutch slave started leaking on me again, you might have seen it posted in the maintenance section. I put it down to corrosion that snuck past the seals and pitted the bore and piston in critical areas.

I could just buy a new one, but I'm looking at north of 200-250 after shipping, duties, taxes, exchange, etc. It's not that I don't have the cash, it's that it seems like a heck of a lot of coin for something so small and simple. Coin I could use elsewhere on things I'm going to have to farm out and pay through the nose for (like paint job, new tires, etc).

Pat pointed me to the post where a guy in BC inserted a stainless sleeve into his old slave. Not a lot of info on it, but it seems to have worked for that gent. It's certainly something I'm capable of in my shop, so I started making plans to build the jig for the lathe and where to source some stainless tube I can ream to size.

But then I started thinking; if I'm going to go that far, why not go all the way?

I've got an RPM oil filter adapter installed:



The RPM adapter is a nice turning, but it means the clutch slave now looks a little "off" without something to butt up against that straight line at the bottom where the OEM filter housing would be. Something is missing and you can tell it is. The look has always bothered me a bit.

I had thought about taking the die grinder to it and see if I could make it look better, but now I'm thinking I might just make a completely "new" clutch slave.

Most of the work I would have to do anyways to insert the stainless sleeve (IE:building the jig).

So my choices are buy a piece of billet (probably 6061) or maybe sand cast a new chunk. Billet means lots of machining, sand casting means close to finished product right off. Strength and porosity of the casting is important since we're dealing with hydraulics, but relatively easy to handle in this application with attention to wall thicknesses and casting processes. As far as actual casting complexity goes, that's a pretty simple shape to make in a sand cast. Essentially a circle with some tabs. The rest is all machine work. I think cast is the way to go, given what I have on hand in my shop to work the metal.

For appearance, I'm thinking something like an FJR:



With the ports, obviously, positioned as needed for the FJ. Round, so it can stand alone in that space. Also, so look like it belongs there with the RPM adapter/filter and not like something is missing.

Long term project, but I think worthwhile. For me if no one else. The "J" isn't going on the road this summer and I'm officially retired end of March, so I've got lots of time to frig with it. Not that I don't have enough projects, but one more never hurts when trying to fill your days!



I've also been looking for an excuse to build a new smelting furnace anyways.

First up is to build the jig to hold the slave on the lathe for machining work. That should be fairly simple: 4-5inches of round stock, a small piece of 1/2" plate and some stock to make spacers to hold the slave.

Too bad I don't have a CNC or I could do some custom logo's of similar. But at least it will be shaped a little better and stainless lined.

Depending on how much of a PITA it turns out to be, there MAY be a chance I would consider running off a couple more, if anyone is interested once I get the first one done. You'd have to provide your own seals and piston though and it would be matched to the piston that I have in my bore, so no guarantees. But it should at least be within production tolerances....

[Bill_Rockoff]

I like the idea of an already-manufactured stand-alone unit that you can retrofit. Does the FJR unit bolt right up? From your photo, it looks like it might, and the only difference would be routing the hydraulic line to the rear and bleeding it from the front.

If you want to roll your own, or adapt something where its built-in bleed valve winds up in the wrong place, there is hardware that allows the hydraulic line fitting to be the same place as the bleed valve.

(Not my photo, just found it looking at Ducati parts:)

[red]

I like the idea of an already-manufactured stand-alone unit that you can retrofit. Does the FJR unit bolt right up? From your photo, it looks like it might, and the only difference would be routing the hydraulic line to the rear and bleeding it from the front.  If you want to roll your own, or adapt something where its built-in bleed valve winds up in the wrong place, there is hardware that allows the hydraulic line fitting to be the same place as the bleed valve.  (Not my photo, just found it looking at Ducati parts:)  

.
Bill,

Good find!  That bleeder-in-a- banjo-bolt is available for any brake line connection, costing from about US$15.00 each and up ('way up!).  
I would use them at the handlebar master cylinders, for most bikes.
Seems possible that you could drill and tap the regular banjo bolts for installing bleeder fittings, but I have not tried that trick yet.  The metal may be too thin there for a DIY, but the commercial units are okay.

[great white]

I like the idea of an already-manufactured stand-alone unit that you can retrofit. Does the FJR unit bolt right up? From your photo, it looks like it might, and the only difference would be routing the hydraulic line to the rear and bleeding it from the front.

If you want to roll your own, or adapt something where its built-in bleed valve winds up in the wrong place, there is hardware that allows the hydraulic line fitting to be the same place as the bleed valve.

(Not my photo, just found it looking at Ducati parts:)

I havent tried an fjr slave, nor do I want to put out the cash to try it. But by the looks of it, the bleeder port looks to be pointed right into the alternator. May be a clearance issue there.

The depth of the housing behind the mounts also looks different, but thats a pure guess from looking at pictures.

This is all assuming the three mount bosses line up, which I'm skeptical they would.

I like the bleeder bolt idea. One less boss to cast and one less hole to drill.

Getting the "meat" on a standard banjo bolt wouldn't be the issue, pass with the welder wouod fix that right up. Getting the right taper on an internal seat for the boeeder to seal up would be a different story though. Less frustration and hassle to just buy one ready-made for the purpose..