small amount of rusty powder in gas

i checked my fuel through the carb drains on my 79 kz1000ltd and found small amounts of what looked like a rusty powder.. is putting an in line filter between the petcock and carbs a reasonable way of fixing this? And, will the filter slow down the amount of gas getting to the carbs? Will i have to re-adjust the mixture?

Welcome to KZr Chris.

Yes, installing an inline fuel filter between the petcock and the carbs is a wise decision to help keep your carbs free of gunk/debris. I recommend the clear or semi-clear type to be able to gauge when it needs replacement.
If the filter you get isn't to massive or to small, AND if you change it out when it has done it's job (you'll see it becomming clogged), then you shouldn't have any probs with it preventing the proper amount of fuel flow that your bike needs.

But your first step should be to thoroughly flush (and seal) the tank to prevent more rust from forming.
Pulling the carbs and doing a thorough cleaning of them as well is also advised - you'd be amazed at just how much a few small pieces of rust or gunk can clog up a carb passage/float needle/main jet/etc and make your bike run like crap. :pinch:

I run the best inline filters I can get, but the carb bowls always have a little very fine rust powder in the bottoms. You do need filters, but that stuff is so fine some of it gets through.

If you are getting that powder, I would remove the carbs and dissasemble them from the holder. That powder has a tendency to build up and block the pipes connecting the carbs together. When I first tore mine apart for rebuild the two straight pipes between 1,2 and 3, 4 were so plugged I could barely get a piece of wire through the hole to unplug them.

The stuff being discussed is rust from the gas tank. Before I disassembled the set, I would remove the floats and float needles and blow carb cleaner in the fuel inlet and see what comes out. If it is really nasty with a lot of reddish sediment coming out, then cleaning is needed; if not, then I wouldn't disassemble. I would highly recommend an inline fuel filter on any bike older than about a week old. Last, get a fuel filter from a bike shop... they will have a flow rate sufficient to feed your carbs. If you buy one at the autoparts store, many lawnmower filters look just like bike filters but the lawnmower filters have VERY low flow rates and you will starve your carbs. Z1Enterprises.com sells the correct fuel filters; buy a bunch as they have some sort of volume pricing and save as you will need to change them out every few months.

Yes, yes, yes, fuel filter yes!
Also, if your tank has some rust--there is a way to use a battery charger to remove it. Worked for me and my 35yr old Z1.

www.altelco.net/~jacil/clay/motorcycle/KElecSetup.html

Just watch the anode so that it doesnt touch the inside of your tank, it wont work that way, and yuo might fry your charger.