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Discussion Starter · #1 ·
I've seen that magura offers a pull style hydraulic slave cylinder. They even offer a kit for a speed triple. Any thoughts on this conversion for a Bonnie. I sit in a lot of traffic on my commute to work and would love to reduce the clutch effort. I've tried different levers etc. plus I like the feel of a hydraulic clutch.
 

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That Moose Racing one looks simple and effective, anybody have one?

Leave it to Mr. F to find these things!
 

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Unfortunately the Magura MC is only offered in 7/8". And they don't sell the slave cylinder separately. Interesting idea but I wonder if there is any practical advantages, being that from the actuator arm back, it's still the stock mechanism. Hopefully a Speed Triple user will chime in.

My Arthritic left hand wants to know!

/M
 

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Years ago they had a device that gave a mechanical advantage called EZ clutch. It was a rather simple device that could be adapted to any bike. It gave nechanical advantage.
 

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Forgive me for the bad intel. I was repeating what I was told by the US importer/distributor. Maybe what they meant to say is that they only stock a limited number of complete kits.

/M
 

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Discussion Starter · #8 ·
Ah! That makes more sense. I've gotten so used to US distributors not carrying the items I want that I have almost stopped looking at the US sites and generally go straight to one of the bigger UK distributors.

Yesterday, I started looking at the templates and it looks like we will need a rear punt vario in a "D" length. Do you concur?
 

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and it looks like we will need a rear punt vario in a "D" length. Do you concur?
I don't think the rear mount would be a good idea, as you'll have all of the slave cylinder between the clutch cable bracket and actuator arm. Maybe too tight of a fit. I much prefer the way the slave cylinder is mounted in the Standard Template 1 photo (albeit reversed in orientation on the Bonneville). Even then, the slave cylinder appears to 'float' in its mounting boss, where I would prefer to see it secured solidly.

Is a 1" (25mm) handlebar master cylinder offered?

/M
 

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I have a take-off that was mounted on a Sportster, obviously 1".
Can't recall being overly impressed with it.
Threads directly into the cover as the stock cable does just like Ernesto's pic.
 

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Initial thought.... Isn't this a solution to a non-existent problem?.. I mean it is not like our clutches are SUPER heavy... also wouldn't this add another variable to possible mechanical problems (cable & hydraulic combined system vice just cable).

But it may just be the Marine in me and the KISS principle. >:)
 

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Has anybody actually fitted a hydraulic clutch actuator system to a standard Bonnie clutch? I'd love to hear what the result was. As far as I can see you would not see any difference. You can only move the clutch lever the same distance whatever system you use, any increase of mechanical effort will be at the expense of a reduced actuator arm movement. You can't get something for nothing whatever gadget you use, that's just the laws of physics.

Just a thought, but have you guys fitted a new clutch cable recently? A new high quality cable makes a hell of a difference compared to a knackered old one.
 

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wouldn't this add another variable to possible mechanical problems (cable & hydraulic combined system vice just cable).
Personally I prefer hydraulic clutches. The hydraulic system mentioned in this thread does not use a cable, so I guess that not having the risk of a frayed/snapped cable is a plus point, as would be the easier actuation. But then I also agree with you when you say that our clutches are not heavy enough to justify the expense and hassle, unless you have some disability where it would make life easier, or have tuned the bike to such a high level that it needs super strong clutch springs.

I went to the annual bike show at the NEC some years ago, and there was a small company there selling electronic gear shifters for the disabled. Just basically a solenoid hooked up to the gear lever and operated by handlebar buttons. I watched in amazement as these things went like hot cakes to people who clearly didn't need them, but it did make a good gimmick.

As far as I can see you would not see any difference. You can only move the clutch lever the same distance whatever system you use, any increase of mechanical effort will be at the expense of a reduced actuator arm movement. You can't get something for nothing whatever gadget you use, that's just the laws of physics.
The difference that you would see is how much easier it would be to pull the clutch lever. It is true that the laws of physics say that you can't get something for nothing, but what you can do is trade off a little actuator travel for more ease of operation. There is more than enough travel in the actuator arm to do this, as long as there is enough travel to disengage the clutch with a little to spare, then the rest doesn't matter.

I think that this is a handy invention for anyone with a disability, but beyond that it simply becomes a novelty.
 

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If you're prepared to sacrifice movement at the actuator arm, people have machined a new hole for the cable nipple that positions it closer to the pivot point on the lever. Bit of a bodge though, maybe someone makes a replacement lever?
 

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If you're prepared to sacrifice movement at the actuator arm, people have machined a new hole for the cable nipple that positions it closer to the pivot point on the lever. Bit of a bodge though, maybe someone makes a replacement lever?
That would make the clutch harder, since you would lose leverage on the actuator arm. To make it easier you would need to extend the arm and fit the cable nipple further out from the pivot point. As far as I can tell, there is no space to do that, and that is where the hydraulics comes in, it amplifies the pressure put on the clutch lever. The loss is in actuator travel.
 

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Wrong way around Ripper; moving the cable closer to the fulcrum reduces the actuator arm movement whilst maintaining the same amount of lever travel so you gain mechanical advantage. Less effort required at the lever but the trade-off is less movement of the actuator arm.

The key question is, how much movement of the actuator arm do you actually need? Just using the span-adjusters on the stock levers can nearly halve the actuator arm movement and the clutch still appears to work normally so maybe you don't need all of that movement?
 

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Wrong way around Ripper; moving the cable closer to the fulcrum reduces the actuator arm movement whilst maintaining the same amount of lever travel so you gain mechanical advantage. Less effort required at the lever but the trade-off is less movement of the actuator arm.
Patrick - if you site the cable to halfway along the actuator arm, halving the distance between cable and actuator arm pivot, you have shortened the lever and therefore it will require more force to operate the lever. You could test this out - try sawing off 3/4 of the handles on a pair of pliers, then seeing how much force you have to apply then, compared to the whole pliers. And if, as you say, shortening the length of the lever requires less effort, why do they make breaker bars?

Also, you are wrong about lever travel. In reducing the distance between cable and actuator arm pivot, the actuator arm would still be free to swing around the same number of degrees, but it would take less cable pull distance to do that. The trade off there would be that it would take twice the force, making the clutch harder.

The key question is, how much movement of the actuator arm do you actually need? Just using the span-adjusters on the stock levers can nearly halve the actuator arm movement and the clutch still appears to work normally so maybe you don't need all of that movement?
I agree, there is more travel in the actuator arm than is needed to operate the clutch. That is one thing the hydraulic system relies on, because pull distance is limited with a hydraulic piston of that size, compared to a cable setup. The hydraulic method does have a couple of advantages in its favour, such as being self adjusting, low maintenence and doing away with the risk of snapped cables as well as making the clutch a whole lot lighter. But it is expensive and in my opinion our clutches are light enough already.
 

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Hi Ripper, obviously I'm not explaining myself well. Yes, you'd be right if you moved the cable closer in on the actuator arm, you'd gain more movement there but you'd need more effort. But I was referring to moving the cable closer to the pivot point on the handlebar lever; other end so you get the opposite effect! There has been at least one post where this has been done, but as I say, it's a bit messy with a stock lever.

The mechanical advantage of a hydraulic system would be entirely dependent on the diameters of the master and slave cylinders. The stroke of the master cylinder will be the same as a Bowden cable but if you have a large diameter master cylinder it will displace more fluid than a smaller diameter. If you have a large diameter slave cylinder then it requires more fluid to move a given distance. So you alter the MA by changing either of the cylinders to achieve the movement required. But the only advantage over a hydraulic setup compared to a cable setup is a reduction in friction; which IMHO is next to bugger all with a heavy nylon-lined Bowden cable on such a short, smooth run. As regards easier maintenance, have you ever heard of anyone having trouble fitting a new cable compared to the bleeding problems, seized pistons, leakages and seal issues you get with hydraulics? Each to their own but I'd agree with GySchmit; KISS.
 
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