petcock and fuel filter

Help please- my 81 xs400 is almost ready for new life- rebuilt carbs, reinstall fuel lines, vacuum line and boom, my petcock is leaking fuel- my bike hasn’t seen oil or car for 30 years so pretty sure the petcock seals are shot- is there an aftermarket petcock anyone can recommend that I can...

I have been what i thought to be a vacuum leak. - It will rev all through the range in neutral but when riding it wont get passed 3k in any gear - I have check the vacuum lines and intake boots and carbs and filters and got nothing. When i removed the vacuum line from the petcock it was...

The PO said the petcock on my tank was bad, so its set to on all the time. (I have an inline fuel filter with a shut off on it don't worry) When I redo the tank this winter, can I just remove the petcock, and run directly?? Also, I need a new fuel filter after the old gas, but was told the...