But I need a single circuit master cylinder? I still don't know why I can't bleed and block off the front halfOriginally Posted by DeathBySnuSnu
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But I need a single circuit master cylinder? I still don't know why I can't bleed and block off the front half
Brakes and clutch
what about something likt this?
http://www.ebay.com/itm/Unpolished-M...fc5005&vxp=mtr
That would probably work pretty good East Coast.
This one is a bit cheaper but not sure what size it is?
http://www.ebay.com/itm/VOLKSWAGEN-V...d3b0ef&vxp=mtr
Yep. A std buggy unit. A good choice.
With a built in resivoir it has to be mounted level.
If you zoom in on the number of that master cylinder, it is merely a standard VW bug early style master cylinder. You can go to your local NAPA parts store and get one pretty much identical for cheaper. You can probably buy the res from them as well. Then you don't have to rely on Ebay sellers shipping the product to ya.
It don't say what size it is.
But i do know that at least one of those stock type iron ones with the threads for the resivoir is a 22mm.
I will go and price one out there thanks, plus I would have to get the ebay seller to ship it to canada
What year would I ask for?
Do not get the 22mm bore unit.
Make sure it is no bigger than 3/4 or 19mm.
ok but whats the difference?
A 34% difference in piston area.
So the peddle will be 34% more difficult/stiffer/harder to push with the 22 than the 19.
oh ok, not sure what size I had in the mock up but it was easy to move with my hand
Ok.
That is not what I am talking about.
The mock up is excellent for helping understand the mechanical connection to the master cylinder.*
But what you are moving there is a near zero load.
Now you have to be able to consume the kinetic energy of 1200 lbs traveling at 70mph and convert it to heat.
You don't want a peddle that takes 800 lbs of force on it to stop you. This is where a mechanical advantage comes in. By multiplying the input with the ratio of levers and piston sizes you can create *a lot of force.
It will take a small diameter master and a large slave to do this. You will need to change the wheel cylinders on the back also.
Brakes and clutch
Right on point Death. Here's a link that demonstrates the master/slave relationship. http://science.howstuffworks.com/tra...hydraulic1.htm One thing to notice is that the bigger cylinder has less stroke displacement than the smaller cylinder. So if your master cylinder is too small in relation to your slave you might not have enough stroke to apply the needed pressure to the brake shoes. Also consider the mechanical ratio of the pedal from foot pad to pivot and pivot to master cylinder tab. If you don't get this correct you might end up having to move your foot 18" to get enough stroke on the master cylinder to develop enough hydraulic pressure to push the shoes out and stop you. Could get exciting!
Remember when you were sitting in high school math class wondering "When am I ever going to use this stuff?" Well, here it is.
Another approach is to look at the pictures posted from other builds. If you can find something in the picture that you know the dimensions of, you can usually "guestimate" the dimensions that they are using.
Exactly vwbug.
Thanks for posting the link!
That is why I do not recommend using a motorcycle master cylinder. Just not enough displacement, even more so for drum brakes. The automotive /dune buggy stuff usually have more stroke length.
Still I would stay 17mm (11/16) to 19mm (3/4) master size and the 22.8mm super beetle front slaves nice condition drums and quality shoes. Or even better yet, get disc brakes.
ok thanks guys
what year should I ask for? would it be for a bug or a bus?
We may need some help from the guys who know some more history.*
But from what I remember. ..
The dual cylinder came in 66 or 67.
So i am gonna say 52 to 65 beetle if you are looking for cheap.
I like that aluminum buggy one you found before.
yeah it was nicer looking and looked more for a bike, but it cost more and I would have to get it shipped into Canada
your talking about this one http://www.ebay.com/itm/Unpolished-M...fc5005&vxp=mtr
Yep that one.
Also solves the problem of mounting the resivoir and/or rubber grommet/ tube of a stock type master.*
I don't have the room for it on mine.
So take in account where you are gonna mount it.
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