So I've had the fuel starvation issue going on and have read as much as I could about fixing it, so far I've been unable to find anything saying to do it this way.  When I tore my petcock apart to attempt to make it a vacuum free valve I decided to try something different.  I took a 15/64" drill bit and drilled all the fuel passages out to the same size to eliminate the PRI position's smaller passage.  I also drilled out the yellowish cone which if you are not careful could be very easy to screw up. 

I got the bike on the highway and it still didn't get enough fuel in the ON position but when I tried again on Prime it worked great.

I really like this fix because it doesn't require any real modification and it's easy enough to switch the petcock over to Prime before getting on the highway.

Sorry if this has been posted before.

only problem with this is once you run outta fuel you are bone dry... even your carbs will be empty.

the bowls in your carbs might overflow when the bike's not running...depending on how healthy the valves for the float bowls are.  that vacuum diaphram closes the petcock and cuts fuel flow to the carbs when you shut the motor off.  they do sell rebuild kits for the petcock...fairly cheap.

I'm only going to be setting it on prime when it's on the highway the rest of the time it will be in the ON position which still shuts the fuel off when the bike is not running...so no worry about flooding the bowls and the reserve is still there, the only modification I did really was open up the PRI passages to the same size as everything else so I can run it on the highway.  To me this was much more simple than modifying this thing and much cheaper.  Everything inside my petcock is in great shape the diaphram is solid and nothing is torn so it was just a matter of me getting my fuel to my carbs cheap and quick.

I personally will continue to run this setup as long as it works and I have the bike.

Over boring the petcock, yes I did it in 1997/98. I however have not had starvation after on any other bike. Cos I figured out the math and how to fix carbs and bikes in general.

Think about this guys. Your petcock no matter how slow it is, will drain a 4.5 gallon tank in just about 10 mins or less.
Assuming you're making 50 mpg, you would run 225 miles on it. Ergo, you would be able to run 225 X 6 mph 1300 mies an hour.

Some thing else is wrong. Your petcock shutting your fuel out is due to a vacuum lock in the tank, vacuum loss from the vacuum line, or downright shitty gas mileage, like lets try 3mpg. So that is 3 X 4.5, so its 14 miles in 10 mins so its 84 mph and 3 mpg. That is not right. You're fixing some other problem with a over bore of the petcock.

Cool.
Buddha.

Buddha you do bring up a good point...something I had not thought about because all I've seen on here is how bad the petcock is.  I guess I'll look at it more in depth this winter when the bike is down.  The tank could use a good freshening up anyway.  I'm going to be tearing into this thing and get some fresh pain on some stuff that needs it and try to make a good enough bike to ride all year next year.

Well try to drain a full tank. See how quick it goes dry. If its over 10 mins you have somehtign clogging it.\
Cool.
Buddha.