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PostPosted: Wed Aug 17, 2011 10:33 pm 
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TRX wrote:
horizenjob wrote:
The clutch handle will work just fine, maybe just a bit better then on a bike because your stronger fingers will be at the end of the lever.


Yes. Some vintage motorcycles pivoted the levers on the outer ends of the bars for just that reason, but it was simpler and cheaper to move the pivots inboard.



Yes some older Harley's, early 60's I think had them for sure and pretty sure some of the vintage Nortons, Triumphs and BSA's had them as well.

Congrats on beating the odds and getting back to the build


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PostPosted: Thu Aug 18, 2011 4:01 pm 
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First and foremost:
It's great to hear that you made it through such an amazingly close call, Joe! It's amazing what the human body is capable of enduring against all odds. :cheers:


In regards to the hand clutch:
Having driven a hand-clutched FSAE car in anger, I can honestly say that it's the only way I would go on any BEC...Although I might try to figure out a way to integrate it into paddle shifters, just to be one of the cool kids. Floor mounted clutch pedals, when not required by design, offer no real advantages on a sequential dog box in my opinion. This also opens your options up to be able to do more left foot braking.

One interesting concept that ties in with the originally posted question is that each end of the cable functions purely on the relative position of the cable end and sheath end to each other. Thus you can physically actuate the cable by holding the cable end stationary, and moving the sheath end. The so-called "butterfly" hand clutch/shifter, pioneered by Bob Woods the longtime FSAE Professor for U of Texas - Arlington, actually utilizes this property such that when you push the close lever away to downshift, or pull the far lever towards you to upshift, the shifter will partially activate the clutch to slip just enough to assist the gear change. For those who don't care to do even a partial clutch on the upshift, you can just pull the close lever towards you. By squeezing both levers together, you fully disengage the clutch for stopping/launching and still have the ability to select any gear. It's really kind of elegantly brilliant. While I've never driven a car utilizing this mechanism, I would probably build a shifter based on this premise, in some form or another.


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FSAE Butterfly Shifter.png
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PostPosted: Thu Aug 18, 2011 11:09 pm 
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I dunno,when I ride bikes I want the clutch at my left hand,when I drive a car I want it at my left foot.My foot cable clutch works great in my car,you don't "need" a clutch to go up or down thru the gears in a bike trans anyways.I only use it for downshifts as it easy to rev match and make them super smooth.
Why make it more complicated than it needs to be?.


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PostPosted: Fri Aug 26, 2011 4:10 am 
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Location: Melbourne, Australia.
Porsche in the late 60's came up with the rather interesting idea of using a vacuum cylinder (similar looking to a power brake booster chamber) to operate the clutch.

As soon as you placed your hand on top of the gear lever, engine vacuum sucked in the clutch.

You could fit an adjustable needle valve to slow down clutch engagement time, so clutch engagement is neither too violent or too slow as you remove your hand from the gear lever.
Porsche also used a torque converter with this system, but it should also be able to be made to work with just a clutch.

This they called the "sportmatic transmission" if you want to do some further internet research.

I think it would be a lot easier to drive than a hand grip clutch, and well within the scope of a home fabricator/tuner to get going.
A micro switch and a vacuum solenoid should disengage the clutch fast.
And a needle valve air bleed that you can tune, to engage the clutch reasonably smoothly is probably all you need.


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PostPosted: Fri Aug 26, 2011 11:05 am 
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Quote:
Why make it more complicated than it needs to be?.


Making something different doesn't make it more complicated. You like the left hand clutch on a motorcycle, but really what other choices do you have? If you like a hand clutch, why not put it on the shifter in a car? It's probably simpler, you all ready have the proper cable and hand grip etc. available.

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PostPosted: Fri Aug 26, 2011 11:33 am 
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Warpspeed wrote:
Porsche in the late 60's came up with the rather interesting idea of using a vacuum cylinder (similar looking to a power brake booster chamber) to operate the clutch.

As soon as you placed your hand on top of the gear lever, engine vacuum sucked in the clutch.

You could fit an adjustable needle valve to slow down clutch engagement time, so clutch engagement is neither too violent or too slow as you remove your hand from the gear lever.
Porsche also used a torque converter with this system, but it should also be able to be made to work with just a clutch.

This they called the "sportmatic transmission" if you want to do some further internet research.

I think it would be a lot easier to drive than a hand grip clutch, and well within the scope of a home fabricator/tuner to get going.
A micro switch and a vacuum solenoid should disengage the clutch fast.
And a needle valve air bleed that you can tune, to engage the clutch reasonably smoothly is probably all you need.


You could use a stepper motor and a potentiometer to accomplish that. ..

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PostPosted: Fri Aug 26, 2011 3:55 pm 
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Driven5, and Andrew T and all others who have posted...WOW, didn't expect so much action on this! Andrew, will keep you posted, as well as all others, BUT....another complication. We are moving to nicer Digs in Broken Arrow OK. I am packing the workshop as fast as possible. I will be changing internet carrier too. I have asked Dave Hempy to help me take care of this.
Driven..That clutch and shift arrangement is Interesting!!!. I had wondered if my clutch grip would partially engage the clutch on the up shifts, sisnce my car is arainged forward push into 1st, and pulling back for gears 2,3,4,5,6. While typing this I have
come up with a simple plan to accomplish the same thing on the way down with the sam lever. Lots of time to plan, but not much time to move. I HATE MOVING!!!
I remain Greatful for all the help!

Joe (99% ALIVE) G.
Crescent, OK. :D


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PostPosted: Fri Aug 26, 2011 7:59 pm 
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horizenjob wrote:
Quote:
Why make it more complicated than it needs to be?.


Making something different doesn't make it more complicated. You like the left hand clutch on a motorcycle, but really what other choices do you have? If you like a hand clutch, why not put it on the shifter in a car? It's probably simpler, you all ready have the proper cable and hand grip etc. available.



I was really taking about the dual lever set-up driven posted,that looks like a lot of effort for no gains other than awkwardness.

As for the clutch on the shifter,I think it would quite alot of practice to get the timing right on the downshifts to be smooth enough(slow shifts for a street car sure,not for the rapid fire downshifts I prefer).Left leg would be doing nothing anyways and the right hand would be doing two things at once,I'm a guy so I'm not supposed to be able to do two things with the same limb at once. :wink:


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PostPosted: Fri Aug 26, 2011 8:11 pm 
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Yeah, on a bike you can squeeze and release the clutch with quite a lot of force, without steering it into the weeds.

On the end of a gear lever however, it is going to take a lot of practice, strength and coordination to get gear changing anywhere near smooth. And you will be doing a lot of shifting.

I still like the button on the end of the gear knob idea that Porsche had.


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PostPosted: Fri Aug 26, 2011 11:42 pm 
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Warpspeed wrote:
Yeah, on a bike you can squeeze and release the clutch with quite a lot of force, without steering it into the weeds.

On the end of a gear lever however, it is going to take a lot of practice, strength and coordination to get gear changing anywhere near smooth. And you will be doing a lot of shifting.

I still like the button on the end of the gear knob idea that Porsche had.



If the clutch lever is on the gear stick then its going to require the same amount of effort to work than if it was on the bike. Same hand(in NZ) + same lever = same effort. Not rocket science.
This setup will only be hard to use if you only have one hand or maybe if your uncoordinated.


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PostPosted: Sat Aug 27, 2011 12:04 am 
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L8 apexr wrote:
I was really taking about the dual lever set-up driven posted,that looks like a lot of effort for no gains other than awkwardness.

As for the clutch on the shifter,I think it would quite alot of practice to get the timing right on the downshifts to be smooth enough(slow shifts for a street car sure,not for the rapid fire downshifts I prefer).Left leg would be doing nothing anyways and the right hand would be doing two things at once,I'm a guy so I'm not supposed to be able to do two things with the same limb at once. :wink:
Each of us is certainly entitled to our own opinions, and when success is achieved with one method it becomes natural to resist change.

I personally would challenge that, like learning any other "muscle memory" motion, with just a little practice a hand clutch on the shifter actually requires less physical coordination than the timing we all hard to learn trying to accomplish the same single fluid task with two separate limbs. I would also challenge that, again with just a little practice, it is more ideal to have two feet operating two pedals rather than three. With a push/pull cable operated shifter, the mechanism can even be mounted on which ever side is more comfortable for the driver...Although a direct solid linkage for the shifter does seem to provide a more 'positive' feel most of the time.

I would also not be surprised if with a little practice to gain familiarity, the intimidating looking shifter pictured above is probably the least awkward of them all, as there is now one less function to operate individually allowing the driver to focus that much more on the driving. There is also probably a pretty good reason or two that one of the best established and most successful FSAE programs in the country continue to run it, year after year.

Does operating part of a vehicle in a newish way take some getting used to? Absolutely. But so did the learning to drive a car, or ride a motorcycle, or to heel-toe downshift. Now I'm certainly not saying it would be the favorite solution for everybody who tries it, but it does have its potential advantages on the sequential dog box in a BEC for some of those willing to try it for themselves.

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Last edited by Driven5 on Sat Aug 27, 2011 12:13 pm, edited 1 time in total.

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PostPosted: Sat Aug 27, 2011 10:53 am 
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Memories of learning to drive a clutch(ok ok I was 11 or 12). ..

Vroom buckbuckbuck clunk, nenenenenene varooom vroomvroom buckbuckbuck clunk, nenenenene varoom buckbuck wheeeeee OH [PooPoo] THE FENCE!! :rofl:

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PostPosted: Sat Aug 27, 2011 11:03 am 
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oldejack wrote:
Memories of learning to drive a clutch(ok ok I was 11 or 12). ..

Vroom buckbuckbuck clunk, nenenenenene varooom vroomvroom buckbuckbuck clunk, nenenenene varoom buckbuck wheeeeee OH [PooPoo] THE FENCE!! :rofl:


:rofl:
Same story, I was about 7 and it ended with OH [PooPoo] THE BARN!!

Was not a good day for me...

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