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Posted by: bdstone914 Aug 27 2017, 10:11 PM

Out of the couple hundred pedal set I have rebuilt it is obvious the smallest bushings were out the most. The one in the clutch arm often wears completely through an starts wearing the arm itself. This happens with both the plastic and bronze bushings. It is a bigger problem on later 911's as they use a longer arms and have stringer pressure plates that accelerates the wear. And for some 911 the clutch shaft is NLA. Thank you Porsche.
I have made a prototype arm that uses a ball bearing to replace the bushing. I have now found a 17mm x 6mm x 6mm skate board bearing that will work.
I have measured the pressure to depress the clutch and calculated the pressure on the bearing is about 25-50 lbs. The bearing are rated for over 500 lb so it should never fail.
I have also toyed with the idea of replacing the clevis pin with a pull type spring loaded ball stainless steel pin. The clevis pins are hard to remove when they wear and there is little to grip to pull them out.
The plan is to make new clutch shaft out of a heat treatable steel with the ball bearing design. Considering stainless for the shaft as the pedal sets often rust badly internally.
The arm portion would be made straight eliminating the dog leg to the arm. A Delrin spacer that is used on 911's would be used to on the shaft to take up the distance of the offset of the original part.
The distance C-C from the shaft to the bearing center could be changed to application with stiffer clutches ( like V8's ) Porsche varied this dimension starting with the SWB cars and made them longer up through the SC's. A shorter arm would give more clutch pedal modulation.
I used to weld up the elongated worn hole and reshape ti round. PITA. The the cost for a new arm with a bearing looks to be in the $20 range.


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Posted by: turnaround89 Aug 27 2017, 10:42 PM

Id love to try this out on my subaru conversion. Not a bad price either. Any idea when they'll be available?

Keep up the great work

Posted by: Krieger Aug 27 2017, 10:47 PM

Nice work Bruce!

Posted by: bdstone914 Aug 27 2017, 10:48 PM

Probably a couple weeks. Is you car up and running Is the pedal hard to depress?

Posted by: Matty900 Aug 28 2017, 01:03 AM

Nice work Bruce!

Posted by: michael7810 Aug 28 2017, 06:31 AM

Excellent work. Having you rebuild my pedals is on my long term list of stuff to do...not sure when but it will happen. Thanks for your support to the community.

Posted by: mgp4591 Aug 28 2017, 08:26 AM

You got the idea from playing with a Fidget Spinner, right??

Posted by: mb911 Aug 28 2017, 08:37 AM

I want one..

Posted by: bdstone914 Aug 28 2017, 08:55 AM

I told my grandson it was a figet spinner. Now he want me to make one for him.

Posted by: mepstein Aug 28 2017, 09:27 AM

Bruce, as soon as you make some, I'm a buyer. Thanks!
I'll also buy one with the longer clutch lever for my 915 conversion.

Posted by: bdstone914 Aug 28 2017, 09:55 AM

I will get some of the longer arm ones made up.

Posted by: Perry Kiehl Aug 28 2017, 10:14 AM

Posted by: Philip W. Aug 28 2017, 10:20 AM

an excellent improvement and solution to a common problem!
I have a pedal set that id like to put one in, so one for me for sure!

Posted by: andys Aug 28 2017, 11:35 AM

Bruce,

Nice work! Did you look at the clevis with the spring retainer available from McMaster-Carr?


Andys

Posted by: bdstone914 Aug 28 2017, 01:34 PM

No, but that is like the original one that is hard to remove it it is worn. I it is used with the bearing it should not were either way. I think it would be easier to have a straight pull pin.

Posted by: Elliot Cannon Aug 28 2017, 02:19 PM

Nice improvement Bruce. Put me down for one.

Posted by: Kansas 914 Aug 28 2017, 02:21 PM

I need at least one - assembly is commencing on the Willow car now that the flared car is finished.

Posted by: whitetwinturbo Aug 28 2017, 09:14 PM

Bruce, we are not worthy...

.........I want for my v8

Posted by: euro911 Aug 28 2017, 09:40 PM

Nice innovative thinking, Bruce

I had to go with a different size bushing when I changed to the hydraulic system. I'll measure the bushing's ID, but also wondering if there's a possibility of sourcing a bearing with the correct ID I'll need.

Posted by: Elliot Cannon Aug 29 2017, 09:31 AM

OK Bruce, get off the computer and get to work on these.

Posted by: malcolm2 Aug 29 2017, 09:46 AM

What about the offset? Is that what the nylon spacer bush is doing for you? and it is OK with the greasy spring? Can you assemble yours and show us the finished product?

I am not from Missouri, but I can fully understand if you "show me".

Posted by: amfab Aug 29 2017, 03:37 PM

I haven't even installed the rebuilt one from you and you are making improvements. Apparently, I need to work faster.

-Andrew

Posted by: bdstone914 Aug 29 2017, 07:08 PM

You can always upgrade.

Posted by: 914forme Aug 29 2017, 07:39 PM

Looks like a deal to me

Posted by: bdstone914 Oct 20 2017, 09:24 PM

I have five shafts available at this time. I am contacting those who expressed interest. I will be doing another batch soon as there were five people who said they wanted one. MB 911 sent me his pedal set and his is built.
Elliot
Mepstein, will need a customer one, Have two made an need to assemble a set to make sure everything is right.
Phillip W
whitetwinturbo

I decided to go with black oxide as a finish. Zinc plating is thicker and often causes assemble problems.
Cost will be $50 for a finished shaft with bearing, spacer (needed as it is a straight arm ) , roll pin and spring loaded clevis pin.
Price is $50 plus shipping. If you want a pedal set rebuilt with the impreved shaft the cost is $250.


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Posted by: porschetub Oct 20 2017, 11:53 PM

Nice to see you repairing them and looking @ improvements along the way,IMO the larger pin is the key to making them better,the original factory clevis leaves a lot to be desired,due to the small pin they wear out the hole in the lever.
The pic is my one before I welded it closed and redrilled.

Posted by: worn Oct 21 2017, 04:18 AM

The part I really like is the new Clovis pin. It isn't as though you have a lot of space to work in when hooking up the clutch cable.

Posted by: BK911 Oct 21 2017, 06:47 AM

Sounds like a lucky guy!
Heard one may be heading to TN too!!!

Posted by: mb911 Oct 21 2017, 07:27 AM

Not this Mb911 so maybe a mix up?.. I redid my own but would be interested in this upgrade.

Posted by: rgolia Oct 21 2017, 08:22 AM

Bruce,
I would like a pedal set rebuilt. What is the process?

Posted by: bdstone914 Oct 21 2017, 08:49 AM

Sorry, I get you two mixed up. it is MK 911.

Posted by: bdstone914 Oct 21 2017, 08:51 AM

Hello,

Send your pedal set to
Bruce Stone
11276 Ramway Rd
Riverside CA 92505

$250 rebuild cost plus $15 return shipping.

Bruce

Posted by: djway Oct 23 2017, 09:14 PM

Im in

Posted by: bdstone914 Oct 23 2017, 09:15 PM

You want a pedal set built with one or just the shaft ?

Posted by: 914werke Oct 23 2017, 09:17 PM

Bruce if you still have stock Ill take one.

Posted by: db9146 Oct 24 2017, 06:01 AM

Hi Bruce,
I've replaced my bushing in the last couple of years but for this mod, I'll go back in. Please let me know when you have another arm,pin, bearing, kit.

Thx

Posted by: wndsrfr Oct 24 2017, 06:17 AM

PM sent for one kit...