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Nothing! The correct answer is .0069 square inches. (you gotta use that pie-r-squared thing)
but … do you see where I'm going with this ?:I
I call BS on that number. Are you talking the walls of the hole, which would be in square inches or the volume of the hole which would be cubic inches. Neither is as small as 7 thousandths of an inch.
 

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I call BS on that number. Are you talking the walls of the hole, which would be in square inches or the volume of the hole which would be cubic inches. Neither is as small as 7 thousandths of an inch.
(pssst... .0069 square inches dictates a hole with a diameter of about .09"....)
 

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I call BS on that number. Are you talking the walls of the hole, which would be in square inches or the volume of the hole which would be cubic inches. Neither is as small as 7 thousandths of an inch.

Fuk, it took me almost 10 minutes to figure it out, you're not going to make me go through all those complex calculations and measurements again are you :rolleyes:
 

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(pssst... .0069 square inches dictates a hole with a diameter of about .09"....)


EDIT/Addition: Dang, I can't the award attachment at work! What'd I win? What'd I win!
That's the area of the open hole only. And it's still more than .0069
 

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(pssst... .0069 square inches dictates a hole with a diameter of about .09"....)

:/ 7 thousandths of an inch is way off, that's less then 0.2mm


0.0938" or 2.3813mm or a 3/32" drill hole if you prefer.
At least, that is the size of the drill that fits nicely into the through hole, on the business end of a brand new Schrader tire valve. (happened to have 1 sitting right here in me tool box)

If'n you need help with the rest of the pie math, click here -> Online Conversion - Circle Solver Calculator



In layman's terms, the actual pressure through the valve is so low, you could remove the valve core and hold a serious amount of air pressure back with one finger :/
 

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:/ 7 thousandths of an inch is way off, that's less then 0.2mm


0.0938" or 2.3813mm or a 3/32" drill hole if you prefer.
At least, that is the size of the drill that fits nicely into the through hole, on the business end of a brand new Schrader tire valve. (happened to have 1 sitting right here in me tool box)

If'n you need help with the rest of the pie math, click here -> Online Conversion - Circle Solver Calculator



In layman's terms, the actual pressure through the valve is so low, you could remove the valve core and hold a serious amount of air pressure back with one finger :/
You did the math right the first time. An 0.09" diameter hole has an area of about 0.007 square inches.

As for holding the pressure back with your finger, the size of that hole doesn't matter, it's the size of the top of the valve stem you'd be dealing with, which is about 1/4" IIRC? That's got roughly 9 times the area of the hole you're talking about, so your finger would have to hold back around 6lbs of force at 120psi.

I have no idea why I care enough about that to post though...
 

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If you're talking about Schrader valves being off topic:

thanks all for all the information, sure game me a lot to think of.
will look for the 550 forks, if i cant find a set, i assume i can use the 750 and protrude them out of the top clamp, right? i know you guys dont like it, but it will be the easiest and safes way for me to mount the 750's forks and maintain the right geometry.

not sure if i should go with single or dual rotors... but will look for different calipers, gixxers est... (unless there is something else recommended for a decent price).
if i'lll have to make an adapter plate for the calipers, so be it.

As for the carbs, where can i get the shorter boots for them ? i assume the old ones are cracked and will have to be replaced, so shorter ones with K&N filters will do.
will also look into fabricating some sort of support to the carbs that replaces the airbox.

any recommendation or link on how to fit a valve on the front forks? any specific valve?

As for braking - i ride motorcycles for the past 20 years or so, many different bike, from off-road to high performance street bikes (currently riding a 97' TL1000S) , but never raced one on an actual/official track... i can only assume i will be able to handle the braking part.

guess i do have a long way to go.
i am moving to a bigger hose next month, so i guess i will use this time to gather the needed parts.

any other information will be more than welcomed.
thanks!
Raviv.

It's Ravivos' thread and Ravinos' topic.

I have installed air caps on some of my motorcycle front forks with success, only trying to help.
 

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...ok, air caps.. why not install install threaded fittings and send two lines to one air valve?

My thinking is if the object is to have even pressures in cylinders that need to move at the same rate, this would be the ticket...

Or would you want two seperate to have air pressure to help overcome any difference they may have ..? use air then to fine tune each ?

OP sorry for the thread theft, seems a logical question to the discussion here..
 

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...ok, air caps.. why not install install threaded fittings and send two lines to one air valve?

My thinking is if the object is to have even pressures in cylinders that need to move at the same rate, this would be the ticket...

Or would you want two seperate to have air pressure to help overcome any difference they may have ..? use air then to fine tune each ?

OP sorry for the thread theft, seems a logical question to the discussion here..
Yup and balanced pressure.
 

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When riding can anyone, besides Whitworth, actually tell the difference in forks that are off by a pound or two? And would you know which leg it was that was low? Yes, a 2-1 valve would work. But wasn't air fittings ultimately just a crutch fix?
 

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When riding can anyone, besides Whitworth, actually tell the difference in forks that are off by a pound or two? And would you know which leg it was that was low? Yes, a 2-1 valve would work. But wasn't air fittings ultimately just a crutch fix?
You called?

Two PSI from the ideal pressures, or a pound difference in balance between the legs? Both are easily felt at seriously high road speeds. I've known other guys with fast old Jappers who've said exactly the same things regarding air fork pressures.

A pound out, in tire pressure is noticeable, too. One and a half PSI out, is well out of the ballpark.

Danger, is my business."
 
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