I don't suppose anyone has a pic of how these things break?
I might be able to work on an alternative, but I've never broken one myself.
I need to find out how these things are failing, so if anyone got pics, it would be greatly appreciated!

You guys are breaking with heavier PP's, right?
Usually ACT ones...
I don't think they are breaking due to stock PP's...


-Ted

 

I broke one, once...

The story goes like this, I broke the third gear on my NA tranny; so I found a used NA tranny. After replacing the broken tranny with the new used one; a week later, the clutch pedal all of the sudden got STUCK (hard as a rock), and would not move at all.

The culprit was the pivot ball! The ball part, broke from the stud, and found its way (somehow) to the fork, succesfully jamming the fork on its resting position.


This happened almost 10 years ago, so the story is not 100% accurate

At the time, I was using the RB street/strip PP, and the unsprung 4 puck disc.

 

Yeah I have broken two in my car. I am in the process of having a stronger piece machined for me. The person who is doing the work ran a computer simulation on the stock and upgraded parts and the upgraded came out to be four times stronger. I don't really want to give any more info than this as I might be producing these.

 

That would be freaking awesome if you could get some stronger ones. I have broken 2 of them in my car. I don't have any pics of broken ones cause I always throw them away upon removal, but yes they break right behind the head or the ball of the pivot. And yes mine broke when I was using the Extreme PP from ACT. I haven't broken one since I went down to an ACT heavy duty PP. ( knock on wood )

 

Wouldn't be too bad to have a couple of guys making these (economics at work).

It's just a matter of optimizing the shaft to be as thick as it can be without interfering with the movement of the fork and still have some meat to hold the spring which holds the fork to the ball. A simple lathe can do the job. Unfortunately, it's only worth doing if you're mass producing using a jig of some sort.

I've thought about selling block off plates, for example, but when I noticed the time and cost to make them out of SS and polish them myself, I decided to make just a couple of sets for personal use. I didn't want to sell something that wasn't up to my standards. The picture shows the plates below my standard (polishing).

Just my opinion on the whole selling RX-7 parts deal.

 

im on my 4th one. im running a act the pressure plate isnt anything crazy. the ball always brakes behind the head and when i pull the trans its alays still held snug in the fork.

 

Which PP though? Heavy duty? Extreme?

My heavy duty has been on my trans for quite some time without issue, I was under the impression that the Extreme was causing the issues.

The broken ***** I've seen (whoa that sounds bad.....) all break at the casting for the "support" of the ball, so thats where reinforcement would be required.

 

I had my ACT H/D pressure plate for years but after I changed the master, it broke.
The Kouki pivot ball is MUCH beefier than Zenki ones. The thread is not the same so you can't use it.
The last one I changed seemed it's made from a different metal than original ones.
It breaks at the weakest point which is right below the ball.
I think you saw it when you came by??
People should change them anytime they do a clutch job. It's cheap.
But, a better stronger ones would be great though.