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Vtwin
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I'm sure something could be fabricated......hmmm I have some tiny cylinders might have to go all mad scientist on this:laugh:
 
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Discussion Starter · #3 ·
Discovered that Wilwood makes a pull type slave cylinder. And its only $35! Its 4" long and roughly 1.75" in diameter. Gotta see how the plumbing connects, but it looks like a go for now. Not sure about operating pressures, travel needed vs travel applied ...etc. Just make a phone call :thumbsup:

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Chief Breakshit Engineer
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Generally push style slave cylinders are preferred due to the fact that its far easier to get a good seal on a push type due to the fact that you only have to seal the piston and with pull types you have to seal the piston and the rod.

I've seen some motorcycle engines that had different covers that would bolt on that allowed you to use a clutch cable that pulled from one side or pushed from the other side. Yes this was a cable clutch, but im not sure how common this type of setup is. Just sayin, you can push from the other side sometimes.

I've also made my own push style slave out of a rear master before (not great to get bled, but functional) that pushed a rod welded on the other side of the typical cable pull pivot.
 

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Discussion Starter · #5 ·
Makes perfect sense bud. Thanks for the insight on that. I have a spare rear master here. Not sure if its good or not. I know my CB clutch throwout is a set of three revolving balls that rotate out of their ramps to actuate. Maybe its reversible? Ill have to take a look. Thanks for the idea!

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Vtwin
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Vtwin
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Turns out my cylinder are to big, but I'm not givin up, the bmill has these little cyl. All over the place


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Discussion Starter · #10 ·
What's a bmill? Speedway has a nice pull type that goes for $35. Good deal, but not familiar with their Rep. Wilwood sells a pull type for.$70 and rebuild kits are readily available. Took some pics and measurements just now. May be able to use a push style or a piston? style. Gonna pick y'alls brain when I get in to post pics.
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Discussion Starter · #12 ·
OK,here's what I'm working with.

These three balls ride up the ramps to push in/disengage the clutch. Not reversible. It will rotate backwards,but you're not using the ramps,so the clutch would be super abrupt. pretty much be like flipping a switch.




When the balls ride up the ramp it spreads the whole deal open pushing on the throwout. The stem that pushes doesn't touch the throwout during engine operation. No bearing there.


And it all rides behind this case,which is sealed.



Stock,the cable comes thru where the steel rod is. If I mount a pull type SC under the engine case it would be tight,but I think I can pack it in there. I'd like to run solid linkage,but if I run out of room I can make up a short cable to connect my clutch arm to the SC.





Crappy photoshop skillz. The red rectangle are s'posed to represent PUSH style SC's. If I flip the clutch actuating around I can get it into thos position. Ditch the outer cover and fab up mounts for a pusher SC. Exposed stuff is cool,but this would just stick out like a sore thumb and I'd most likely just beat it to death by accidentally kicking it all the time. Plus,it wouldn't clear my kick starter,which I kinda dig.


Another idea was to use a piton style and weld mounts to the clutch cover to hold it in place. I'd have to make some sort of pushrod to connect from the SC's piston to push on the throwout. That'd be easy enough,but the seal that goes here isn't really designed to operate around a spinning part like that. The stock pushrod stay stationary. The seal MIGHT hold up to the rpm's,but there's no way to stabilize whatever pushrod I'd make to keep it from flopping around. I guess I could make a bushing and press it in where the seal goes and then mount another seal outside all that. I dunno. A pull type just seems like the best option in this case. Thoughts? I'm wide open for idears!
 

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Chief Breakshit Engineer
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So basically that little shaft diectly attached to the clutch itself gets pushed? operation would be similar to a typical motorcycle slave cylinder, and I would look into how you would install one of those onto that black cover

 

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Discussion Starter · #14 ·
I would have to make something to connect from the SC to the clutch itself, which is where my concerns about.bushings and seals came. But mainly, I just.worry about my foot with a SC like that. Notice where the foot peg is? It'd be right in my ankle
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Discussion Starter · #15 ·
Found this at my buddys shop. Nice and slim, shouldn't interfere with my foot at all. Its a Maturation setup designed for a Cannondale??? Anyway, I can pick it up for $40 if I want it. Problems with this setup : 1- included lever / MC away wont clear with my preexisting switchgear. 2: not sure if this slave cylinder will jive with my Ducati 916 clutch master. 3: The bearing in the end is going to require constant lubrication. If I mount it "dry " its not gonna last. Hmmm...the plot thickens.

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Discussion Starter · #16 ·
It has a marking that says "9.6"on it. I don't know if that denotes the bore size, or if it means anything at all.

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Chief Breakshit Engineer
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Yeah that MC is a 9.5mm bore. Thats tiny. Usually those balls for use with clutches dont need any lubrication. I just wonder where you'd find a M/C of the same size but of a different construction. That exact M/C is all that ebay seems to turn up.

However, looking up that slave cylinder I came upon this:

http://www.magura.com/en/powersports/products/clutches/hymec-street.html

Looks pretty spendy, but its an entire setup that seeks to do what you originally wanted to do. Conversely, it looks like it has the same M/C that the other one has, which apparently doesnt clear your switchgear. Wonder why they would make a M/C that doesnt clear some switchgear. Either they fucked up or you are using particularly bulky/uncommon switchgear.

They do offer just the slave: http://powersportskatalog.magura.co...737265.html?osCsid=9ehni1oaunqrfh7hv826ssjt60

but I imagine it would require the same 9.5mm bore M/C. You could stray a little, but performance would suffer. Too little travel if you went too small and too stiff of a lever (and possible overtravel of the slave cylinder if you went any bigger (though the only way i imagine going smaller M/C bore size if you used a MTB master, which presents more issues) You could limit the stroke of a bigger M/C by putting a stop in the MC bore.

Slave can be had for ~$85: http://www.powersportparts.net/ProductDetails.asp?ProductCode=4800169

I dont know what the part numbering scheme is like, but the fact that different part numbers exist for the same general part indicates either a few different configurations or a few different sizes (bore/stroke?)
 

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Discussion Starter · #18 ·
Thats a ton of info! Thanks bud!

This setup is sold as a replacement for a Cannondale dirtbike. I doubt that particular dirtbike had any sort of witch gear,so keeping it compact to the bars may have been the reason for the short design.

My switch gear is 69-78 CB750,which is old,but not really all that bulky.

The clutch mc I have coming is off a Ducati 916. No clue what the bore size on that one is,and havent had the time to research it yet. Mixture of busy and lazy,to be honest. But like you said,I don't want to over-travel the slave for sure.
 
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