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So is 10psi too much? Didn't you talk about 18psi as a limit,what is that under load, about 100psi?
I have yet to find a Schrader valve that the top limit does not FAR exceed what is required for a fork (usually less than 10psi). So did the factory "over engineer" the part , or just use what was commonly available which was just any Schrader valve.
Go back and read all I wrote about air fork pressures. You didn't comprehend it the first time.

Danger, is my business."
 

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When it comes down to it, a schreader valve is just a tube with a chamfer in one end with a spring loaded rod that has a cone on one end that matches the chamfer in the tube. when you attach an air source to the valve, it compresses the spring and pushes the cone out of the chamfer.

This allows air to enter.

When you remove the air source, the spring rebounds returning the cone to it's chamfer.

This seals your air chamber. AS long as you keep your core tight, it'll seal well.

For a pump, go hit up a good bike shop for a low pressure shock/fork pump. Anything for older Marzocchi Bombers will work.
 

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Go back and read all I wrote about air fork pressures. You didn't comprehend it the first time.

Danger, is my business."
I read all you had to say. When you said "10psi is like 60psi at load", were you just stating numbers or advising against 10psi? One post says 8-12psi is normal, so the 10 I mentioned should be spot on and 60psi at load is good. You said exceeding 18psi is bad, so what about 15psi?

Someone should mount a pressure gauge on their Schrader valve and see what pressures are generated during use. That might actually be more of interest than anything Whit has to say.
 

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Gee, it sure seems like a life. At the racing on Sunday, hanging with a little blonde racer. She smiled like the Sun, all day long with pearly white teeth. She had far too much beaming positive energy. Hard to believe, but all too true. Then off to the hipster cafe, to slurp and look at the funky cats.

I know what type of valve works best, because I've tapped, fitted and used plenty of them. Some close quicker and are easier to adjust the pressure without excessive air pressure loss. That's experience for ya.

Danger, is my business."
To tell you the truth, control for closing the valve is in the pump. The faster it disconnects, the faster the valve will close (after all, air pressure and the spring are both trying to close the valve...). And even then, any PSSSSSSSSSCH you hear upon removal is primarily from the air line, not the now closed valve.
 

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Gee, it sure seems like a life. At the racing on Sunday, hanging with a little blonde racer. She smiled like the Sun, all day long with pearly white teeth. She had far too much beaming positive energy. Hard to believe, but all too true. Then off to the hipster cafe, to slurp and look at the funky cats.

I know what type of valve works best, because I've tapped, fitted and used plenty of them. Some close quicker and are easier to adjust the pressure without excessive air pressure loss. That's experience for ya.

Danger, is my business."

Nothing it writes actually says that it rides a motorcycle :|
Wit stick with danger, you obviously don't know shite about the business of riding motorcycles. Being a bicycle rider, you probably don't even own an accurate low pressure air gauge.
 

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Nothing it writes actually says that it rides a motorcycle :|
Wit stick with danger, you obviously don't know shite about the business of riding motorcycles. Being a bicycle rider, you probably don't even own an accurate low pressure air gauge.
TR, if he actually understood bicycles, he'd understand how a fucking schrader valve worked...

Hey Walter, you have quick closing valves on that BMC?
 

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Discussion Starter #71
trying to get the threat back on on track (no pun intended)

Hi TR,
not planing on replacing the entire front end, just the suspension... i want to keep the original wheel and i assume that the center hub have a specific (and rather small) bearing seat.
will go with fork brace, as i assume it will be almost impossible to convert the front axial to a thicker one due to a rather small outer diameter of the bearing.

Hi Tom,
Got one of these pumps at home from my freeride bicycle riding days, will sure use it, thanks.
 

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:I say go with 4 and a half pounds of air pressure in each side, and if you can't measure air pressure to within half a pound, you are probably not in the performance motorcycle business.
 

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Discussion Starter #73
Hi TR, guess i have to sell all my bikes and buy a proper pressure gouge that can read half a pound... :)
Hi Diamond, will get me one of those as well for the case pressure test.

have to say, you guys are more than helpfull, and gave me a lot of material to think of.

Ravivos.
 

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Hi TR, guess i have to sell all my bikes and buy a proper pressure gouge that can read half a pound... :)
...
:/ the one I carry with me in my fanny pack when I'm riding cost less then 10$ and reads up to 7psi

… I have no idea why these guys want to make one of the simplest modifications you could ever do, sound so freakin expensive and involve rocket science.
 

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Here is a little test quiz to see if y'all understand what Pounds per Square Inch means:

… how many square inches are there in the hole through a Schrader valve ?:I
 

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Jut to go back a couple of pages, brakes are easy. For sure GS disk rotors are lighter but try a modern disk and feel the difference. I used CBR600 disks on a gt750 hub with SV650 calipers and adapter brackets. http://pinkpossum.com/GT750/phattrakka2/p5brakes.htm They haul that bike down from over 100 per with zero drama and they are light.

I replaced those caliper brackets with another pair and had alloy adapters machined by a local machinist. And Of course I did not use those stock rubber hoses on the bike. IT has lack braided hoses for a firm feel.

GT750 forks are OK but can be improved with Gold valves. Not light but they work OK.
 
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