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PostPosted: January 20, 2020, 11:53 am 
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Joined: April 1, 2010, 10:26 am
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I have to remove the pedal box for a couple of reasons.
1. To weld the lower roll bar mounting slug
2. Add a mechanical brake light switch.

After deciding this was going to be a real pain in the ass, I started to look at the brake bias adjuster and this does not look correct. I have attached a simple stick figure diagram. I think this issue is the Pivot Point in red should be attached to the middle of the tube, allowing the leverage ratios to be changed by adjusting the center screw. My problem I think is that the Pivot Point in red is floating within the tube, so adjusting the adjusting screw basically makes no difference.

Graham


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PostPosted: January 20, 2020, 12:05 pm 
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The red is supposed to float in the tube. The screw walks it back and forth to change the leverage between the two masters. It allows the pedal and master pushrods to stay put but change where you are pushing.

Just need a lever switch for the brake. Finger on pedal keeps the switch compressed until brake is applied so the finger swings away from the switch.

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PostPosted: January 20, 2020, 2:46 pm 
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Good news, thanks for the insight.

Graham


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PostPosted: January 21, 2020, 11:09 am 
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Graham there is a subtlety to that assembly. When installed correctly, the center tube with the pivot is nearly clamped by the pivots for the master cylinder. It should be loose enough to allow the assembly to take up slack on the two master cylinders, there will be a slight difference in stroke before the pads hit the disks. Then it should bind up - if there is a failure in one circuit, this binding is all that will give you pressure on the remaining circuit.

So, loose enough to adjust but no more...

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PostPosted: January 21, 2020, 12:29 pm 
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Thanks for the info, there was definitely to much slack so I will fix that on re-assembly.

Graham


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PostPosted: February 23, 2020, 10:16 pm 
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So I thought I'd try to make my own bias bar. The threaded bar is 7/16-14. I can probably find a stud or bolt with a higher strength rating. It seems like you could probably bend this if you tried (4:1 ratio). I think I calculated 50 lbs on the brake pedal is damn near 30,000 psi in the bar.

The barrel nuts are 5/8 diam.

But then I see the Wilwood unit appears to be using a 3/8 bar, so maybe this will be ok?

Thoughts? Just get the Wilwood one? Is this a "hold my beer" moment?


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