Balance Bar .... REVEALED!!

[jhaynie]

Apologies to the Weavers for my ignorance of the workings of the balance bar. The book is worded right, and I got off my lazy a$$ to take the thing apart and see how it really works. Seeing the "neal assembly"(thanks rdorman) really made me understand how it works. Threading the threaded rod back and forth changes the position of the bearing and thus changes the attitude of the clevises when the brakes are applied.

I'm still not sure what is the correct position for the push rods.

John

[jhaynie]

http://www.uniquecobra.com/uploaded/jhaynie/exploded view.JPG

http://www.uniquecobra.com/uploaded/jhaynie/sleeve bearing.JPG

[jhaynie]

http://www.uniquecobra.com/uploaded/jhaynie/exploded view.JPG

http://www.uniquecobra.com/uploaded/jhaynie/sleeve bearing.JPG

[rdorman]

I STILL have to stop and think about the balance bar. What is it you are unsure of about the push rods?

The thing with the push rods is to adjust their indendant length so that the balance bar never binds in the peddle assembly. That is only the bearing contacts the peddle assembly and nothing else. It the adjusting rod or the part that attaches to the push rods cause the balance bar to not be able to move freely when the peddle is depressed then the balance will, at the worst times, completely change.

As for the length of the pushrods, that is for you! Adjust them together, in and out, to move the peddle closer or further from you for your driving enjoyment! Key here is not to move the peddle so far back that it over centers when depressed. If it does then you will have a situation where as you push further the force transmitted is decreasing in relation to the actual force applied to the peddle. Man, that did not come out well. Just dont do it!

Have fun

Rick

[rdorman]

I STILL have to stop and think about the balance bar. What is it you are unsure of about the push rods?

The thing with the push rods is to adjust their indendant length so that the balance bar never binds in the peddle assembly. That is only the bearing contacts the peddle assembly and nothing else. It the adjusting rod or the part that attaches to the push rods cause the balance bar to not be able to move freely when the peddle is depressed then the balance will, at the worst times, completely change.

As for the length of the pushrods, that is for you! Adjust them together, in and out, to move the peddle closer or further from you for your driving enjoyment! Key here is not to move the peddle so far back that it over centers when depressed. If it does then you will have a situation where as you push further the force transmitted is decreasing in relation to the actual force applied to the peddle. Man, that did not come out well. Just dont do it!

Have fun

Rick

[jhaynie]

Thanks for the tips Rick. I put it all back together last night with a guy who know more about brakes than I do. I just threaded about 3/4" of each pushrod into the clevises and left them like that. After looking it over, we think I have a bad front master cylinder so I ordered one of those. The rear cylinder gives a real hard pedal, but the front has 4-5 inches of travel and the fluid in the MC reservoir is barely affected by pedal movement.
I also ordered some of those D type "racing" pads from Wilwood. The warranty disclaimer says they are for off road use only??? That's going to be tough on my Cobra, but I'll try anything! Ha Ha.

[jhaynie]

Thanks for the tips Rick. I put it all back together last night with a guy who know more about brakes than I do. I just threaded about 3/4" of each pushrod into the clevises and left them like that. After looking it over, we think I have a bad front master cylinder so I ordered one of those. The rear cylinder gives a real hard pedal, but the front has 4-5 inches of travel and the fluid in the MC reservoir is barely affected by pedal movement.
I also ordered some of those D type "racing" pads from Wilwood. The warranty disclaimer says they are for off road use only??? That's going to be tough on my Cobra, but I'll try anything! Ha Ha.

[excelguru]

Aha! The secret is revealed! Here's how it works:

John and Rick (the MC piston rods) are holding a long piece of pipe (the balance bar) by the ends. I (the adjustable center bearing) sit in the middle of the pipe. I don't really weigh 200 pounds (pedal pressure), but let's suppose I do to keep the math simple. John and Rick are each tasked with 100 pounds (equal force to front and rear brakes).

Now, let's suppose I move towards Rick such that 1/4 of the pipe is on Rick's side and 3/4 of the pipe is on John's side (we have adjusted the balance bar). This gives John mechanical advantage (leverage). Now Rick is tasked with 3/4 of my weight (or 150 pounds) while John only needs to handle 1/4 of my weight (or 50 pounds). Pedal pressure has been biased towards Rick and away from John.

And that, my friends, is called statics. Plain and simple. Now it makes sense to me. Screw it towards to the front MC for more front brakes and vice versa.

Hope that helps.

Keith :)

My "homepage" is my photo album.

[excelguru]

Aha! The secret is revealed! Here's how it works:

John and Rick (the MC piston rods) are holding a long piece of pipe (the balance bar) by the ends. I (the adjustable center bearing) sit in the middle of the pipe. I don't really weigh 200 pounds (pedal pressure), but let's suppose I do to keep the math simple. John and Rick are each tasked with 100 pounds (equal force to front and rear brakes).

Now, let's suppose I move towards Rick such that 1/4 of the pipe is on Rick's side and 3/4 of the pipe is on John's side (we have adjusted the balance bar). This gives John mechanical advantage (leverage). Now Rick is tasked with 3/4 of my weight (or 150 pounds) while John only needs to handle 1/4 of my weight (or 50 pounds). Pedal pressure has been biased towards Rick and away from John.

And that, my friends, is called statics. Plain and simple. Now it makes sense to me. Screw it towards to the front MC for more front brakes and vice versa.

Hope that helps.

Keith :)

My "homepage" is my photo album.

[GeorgiaSnake]

Thanks guys, looks like yet another trip into the fotbox to check my adjustment [B)]

A cockpit adjustable brake bias is in my future [8D]. I'm to old and stiff to be climbing in and out of the car upside down. :D

Randy



Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver

[GeorgiaSnake]

Thanks guys, looks like yet another trip into the fotbox to check my adjustment [B)]

A cockpit adjustable brake bias is in my future [8D]. I'm to old and stiff to be climbing in and out of the car upside down. :D

Randy



Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver

[excelguru]

Getting into the footbox isn't that hard. It's getting out that's a problem! LOL!

Keith :)

Unique 427
Southern Automotive 462
Jodeco Auto Body paint

My photo album is my homepage.

[excelguru]

Getting into the footbox isn't that hard. It's getting out that's a problem! LOL!

Keith :)

Unique 427
Southern Automotive 462
Jodeco Auto Body paint

My photo album is my homepage.

[GeorgiaSnake]

LMAOSITFB:)

Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver

[GeorgiaSnake]

LMAOSITFB:)

Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver

[weaver]

Randy, maybe you can translate that for me sometime.

Alan

[weaver]

Randy, maybe you can translate that for me sometime.

Alan

[jhaynie]

Now if I had only remembered what they taught me in statics I would have saved myself alot of trouble. Thanks Keith.

[jhaynie]

Now if I had only remembered what they taught me in statics I would have saved myself alot of trouble. Thanks Keith.

[eliminator]

Here is one of them....

Eliminator

[spd4me]

excelguru
If what your saying is correct then the side of the pedal with the most threaded rod showing is the side that is getting the most force? I'm curious to know is the round ball attached to the threaded rod so it turns as one unit? I read somewhere about balance bars and it said the side with the most threads sticking out is the side with the most pressure on it.

[clayfoushee]

That is correct spd4me, the longer side of the bias rod gets the most downforce, hence more braking. If you want more braking in the front, then more of the threaded rod should be showing on the clutch pedal side. The "round ball" (your teminology) is not threaded, and the threaded bias bar slides freely inside it. Just loosen the lock nuts on either side and you should easily be able to turn the rod in the direction you want the most bias. Then tighten down the lock nuts and you're done.

Clay

Unique 9299, 427FE side oiler, top-loader (close), 3.31 rear

Annapolis, MD

[casaleenie]

quote:Originally posted by GeorgiaSnake

LMAOSITFB:)

Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver




I think I've got most of it figured out but I'm missing the OS and quite possibly all of it... Com'on Randy .... come clean...:(

AL

[pgermond]

Sounds like you are fighting the same thing I did. I was convinced that I had a bad from master cylinder. Tkae a look at this topic and see if it sheds any light on your problem - http://www.uniquecobra.com/topic.asp?TOPIC_ID=415

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[excelguru]

LMAOSITFB...

Laughing my ass off stuck in the floor board?

Keith :)
Unique Motorcars (http://www.uniquecobrareplicas.com)
Southern Automotive (http://www.southernautomotiveengines.com)
Bruce Bunn (the painter) (http://www.jodecoautobody.com)

My Photo Album (http://members5.clubphoto.com/keith355593/owner-429c-1.phtml)

[jhaynie]

One assumption we all made is that everyone's master cylinders are configured the same. Anyone have them in a different order on the firewall? Something to think about.

[clayfoushee]

J, Very true and good catch. But, it's very simple to look where the brake lines from the master are running (front or back brakes). I think the vast majority are (from driver inner fender toward engine: 1) Clutch, 2) front brakes, and 3) rear brakes. You want the longest side of the bar exerting pressure where you want the most braking, hence the way we've been discussing it here. If someone has it reversed, you'd just move the bar in the opposite direction.

Clay

Unique 9299, 427FE side oiler, top-loader (close), 3.31 rear

Annapolis, MD