Hand Clutch

[Gary]

Hi Guys,
This si the first year we are running a hand clutch and we are finding it very hard to actuate. Anyone else with a handa F4 experiance the same problem? If so how did you overcome it?

also, which side of the shifter do you place the clutch lever? on the down shift or upshift side? thanks guys.

[MikeWaggoner at UW]

Make sure you have a similar level ratio to the bike's original pull; it was originally a hand clutch after all.

The lever should be on the downshift side. Clutch->downshift (pulling back). Then you can downshift and let the clutch out slowly in one smooth motion. You don't need the clutch on upshift.

[Charlie]

Hi Gary-

With the right ratio it should be easy. However make sure you have a positive stop, or you can shear the head off the clutch pin. Also, if you are having problems getting the clutch to dis-engage while the car is not running, I've seen that too. We've spent a long time thinking our clutch was broken when really it was just not lubricated from sitting.

[Christopher Chow]

Maybe you just need some specialized hand strengtheing tools.

http://malt.dynu.com/~sae/gallery/albums/nifty/picture553_07Aug04.jpg

[Colin]

we had good luck with a hydraulic hand clutch in 2002 it gave a good feeling and was very reliable, we had it actuating off the shifter leaver automatically on down shift, it was very nice to drive

[RagingGrandpa]

Clutching when downshifting? What is this nonsense!?! http://fsae.com/groupee_common/emoticons/icon_wink.gif

Make those dog teeth work for you

[Colin]

----------------------------------------------
Clutching when downshifting? What is this nonsense!?!
--------------------------------------------

Three words "matching the revs" http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Christopher Chow]

so where both the linked clutch and the hand clutch hydraulic? or was your downshift linked clutch a seperate system?

[Colin]

The clutch on the shifter was the only clutch on the car. To launch the car the shifter lever was pushed forward to disengage the clutch and then the slowly released to get the car going. The clutch master cylinder was inline with the gear actuating shaft so when the master cylinder reached the end of it's travel it actuated the gear change, there was a bit of playing around with ratios to get the forces right but it worked well

[Nate Notta]

I'm starting to think the hand clutch is the only way to go.. with three pedals the footroom is pretty scarce.
Can anyone think of disadvantages of a hand clutch compared to a pedal clutch?

Nate

[Colin]

A foot clutch really hinders the drivers ability to left foot brake, which is a pretty important technique in FSAE driving. The only down side I can see to having a hand clutch is launching the car for the acceleration run and that is only because most people are used to using a foot clutch but with practice there is no reason why it couldn't be just as good

[Charlie]

CG.

http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Nate Notta]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Charlie:
CG.

http://fsae.com/groupee_common/emoticons/icon_biggrin.gif <HR></BLOCKQUOTE>

Touché

[Colin]

yea, you got me http://fsae.com/groupee_common/emoticons/icon_wink.gif

[DontAsk]

Left foot braking is an important technique if you practice it enough. I some cases it will make a driver slower... witness Rubens Barichello's comments regarding LFB.

[Jon Huddleston]

UTA has been using an integrated clutch/shift "butterfly" for at least the past 15 years. Either hydraulic or cable depending what was required by the engine. We currently use F4i engines and the clutch should be on the downshift side like mentioned earlier, but our system is a forward downshift except for 1st of course. Try making the clutch arm on both engine and shifter longer, will increase hand travel but requires much less force. Left foot braking is a definite advantage. The biggest difficulty is learning to shift/clutch with your left hand but once that is accomplished you don't even think about it.

-Jon Huddleston
UTA '04 Team Captain

[Denny Trimble]

Unless you're using a solid rod from the shifter handle to the transmission, there's no reason to keep the shifter on the left side. I even saw RIT modify their engine in '98 to have the shift arm stick out the right side of the tranny.

I enjoy watching our new people learn to drive a car with two pedals and a clutch integrated into the shift lever. Sometimes they'll try to coast into the pits and want to push the clutch pedal, but end up locking the brakes and almost smacking their helmet on the steering wheel. Lots of fun... http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Colin]

i don't know what you guys are on about the shifter is supposed to be on the left? http://fsae.com/groupee_common/emoticons/icon_wink.gif

[PipeBom]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Colin:
i don't know what you guys are on about the shifter is supposed to be on the left? http://fsae.com/groupee_common/emoticons/icon_wink.gif <HR></BLOCKQUOTE>

Agreed. Next thing they'll be telling us is that we are suppost to drive on the right hand side of the road... http://fsae.com/groupee_common/emoticons/icon_razz.gif

[mike240z]

What?!? Right hand side of the road... isn't that a little dangerous?
We've had similar instances of people locking up instead of pulling the clutch, and trying to find the brake with their right foot at the end of the straight. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif
Most of the time our drivers don't have any problems, but every now and then they forget what their driving.

[Jon Huddleston]

Denny, your right about the no need for the left side, we currently do not have a single linkage. The reason behind it is simple packaging and its what our drivers have trained on(older cars do have a single linkage). I have driven FF's with normal right-hand h pattern gearbox and another top driver has shifter kart experience. We have learned in the older UTA cars to shift/clutch with the left hand and takes minimal adjustment time. I guess we'd probably be more interest in going to electronic shifting before switching to the right side since the system would require some re-design and it would suck to have our most experienced drivers miss shifts cause they were grabbing for left side when it was on the right. I've been driving the newer UTA 03/04 cars for about a year now and I don't think or remember anything about the shifter/clutch being on the left side while I'm driving. I don't think its holding us up any!

[drivetrainUW-Platt]

workin on the 2005 shifter design right now, could someone explain the butterfly intergrated clutch system, our 2003 car had an integrated clutch that would be activated with a lobed cam on the handle. things wore and it didnt allow for much adjustment anyways...this year we went with the bike handlebar clutch, but havent got to test it yet, still no working brake system http://fsae.com/groupee_common/emoticons/icon_mad.gif one of these days we will finish the 04 car so we can start on the new one!! i know everyone likes to "feel" the clutch, but a properly working integrated clutch would be great.

[alfordda]

Ok, I've driven 6 cars, and they all had differnt clutch/shifter mechanisims. I have to say given about 15-20 mins in a car and spinning it once or twice you'll know where the clutch and shifter are. But, I agree once you find a good location for the clutch/shifter leave it there, that 15-20 mins could be used better elsewhere. But is it ever interesting watching the new guys.

Butterfly system:
Really nice setup, this is probably my favorite mechanical setup. You squeeze two handles to actuate the clutch and then push or pull to shift. Think of a diamond. The bottom point is the shift cable attachment, the middle two are the pivots for the clutch handles, and the top point is the pivot for the shifter. Get all those point right and the levers on the engine and you'll have a bullet proof system.

One lever clutch/shift:
This setup you pulled back to engage the clutch, and then pulled back farther to downshift. It was not possible to use the clutch for upshift. The clutch force was kind of high, but it could have been decreased with some modification.

Elec. Solenoid Shift w/o interupt and clutch lever:
This was our first attempt at a push button shifter. It took alot of experience to get it to shift, but the clutch was great sittin there on the right side. Alignment of this type of shifter is critical. We burned up one, and bent the rod on another.

Elec. Solenoid Shift with interupt and clutch lever:
Much easier to shift, and the clutch was the same.

3 Pedal car:
Like I said 15 mins and a spin and you'll have it down. At least for the clutch, using the brake to the fullest is a different story. I took out a whole corner full of cones, because I wasn't used to the clutch/braking situation.


Gear Motor Shift with interupt and clutch lever:
Mounting has been a little complicated, so not all the bugs are worked out. But the hand clutch was the same.

Bike clutch attached to shift lever:
This system you sqeeze the clutch and shifter and then push to shift down. This system was awkward for take off. Once you were going it was fine, becase the forces were setup so that the clutch would engage before the downshift occured.

Shift lever on the left, Clutch pulled out from the dash on the right:
This was supposed to be an electronicly shifted car, but it fell through. Since this was thrown together the components were not sized properly, and it broke. But once that was taken care of the shifter was great. The clutch was interesting, instead of a lever on the side of the car, we decided to put a handle on the dash that you pulled. The reason was to get the clutch closer to the hand, therefore decreasing the time to engage it. The lever arm to actuate the clutch cable had to be about half the size as the lever that would have been on the side. This produced a larger throw than we really wanted. Needless to say we really only use the clutch for starting.



Why do you need three pedals, you only have two feet. That is unless you are into that whole limb grafting thing, or you played in nuclear waste as a kid.

[RagingGrandpa]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Denny Trimble:
I enjoy watching our new people learn to drive a car with two pedals and a clutch integrated into the shift lever. Sometimes they'll try to coast into the pits and want to push the clutch pedal, but end up locking the brakes and almost smacking their helmet on the steering wheel. Lots of fun... http://fsae.com/groupee_common/emoticons/icon_smile.gif <HR></BLOCKQUOTE>
We pretty reliably have first-timers get in and be used to using the left foot for the clutch, on those long straights they get to redline and then lock the tires as they're trying to shift... slamming the brake and slamming the clutch have very different effects...

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by alfordda:
One lever clutch/shift:
This setup you pulled back to engage the clutch, and then pulled back farther to downshift. It was not possible to use the clutch for upshift. The clutch force was kind of high, but it could have been decreased with some modification. <HR></BLOCKQUOTE>
Pull back to downshift? The simplest shifter linkages are push to downshift, pull to upshift...

Clutch on the steering column (behind the wheel) was different for us this year but everyone on our team got used to it, like you said, after 15mins and a spin.

[alfordda]

That was on our 01 car. It had an old Yamaha engine, ??FZR??. It just used a push/pull cable for the shift and pulled the cable to do the downshift. I wish the car was still around, because I don't remember how it attached to the engine.

[simonsuarez]

hi guys can anyone give me some pointers on this subject different types of shifters? Is there any books about it or should i just go and ask my mechachic? is it better for a rookie team to go with 3pedals or ... any advice would be great.

Simon Suarez
Equipo FSAE-LUZ
Drivetrain

[Bri]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Jon Huddleston:
UTA has been using an integrated clutch/shift "butterfly" for at least the past 15 years. Either hydraulic or cable depending what was required by the engine. We currently use F4i engines and the clutch should be on the downshift side like mentioned earlier, but our system is a forward downshift except for 1st of course. Try making the clutch arm on both engine and shifter longer, will increase hand travel but requires much less force. Left foot braking is a definite advantage. The biggest difficulty is learning to shift/clutch with your left hand but once that is accomplished you don't even think about it.

-Jon Huddleston
UTA '04 Team Captain <HR></BLOCKQUOTE>

We have an F4i engine as well and were thinking of running a solid shaft from the shifter down the legft side and then using a scissor shaft up to the hand clutch and getting the length based on how far the shifter has to move. We were hoping to have a forward push upshift and a normal clutch lever on the finger side of the shifter...this is my first time really going at it, does it sound like we are on the right track with this and does anyone have any advice for me?
Thanks
Bri http://fsae.com/groupee_common/emoticons/icon_smile.gif
"FLY NAVY '05"