Parked in 1994 with a full tank

[MadJack57754]

OK, here goes.
bought a '83 GS11 from a woman that was her husband's bike. He died in 1994 from a massive heart attack.
Took a while to get keys, title, ect, but in my garage now. Showing 6733 miles.
Haven't tried to start it, and will not until carbs are cleaned. Motor is free.
Here is my problem... tank sat since parked with fuel in it. Fuel has evaporated and now the dry crusr is lefr. I have scraped away where I could reach and under the garp appears to be somewhat rust free. Anyone have any ideas on how to get that crap out..
I have thought about a radiator shop ( but the local radiator guy says not to do it S he cannot guarentee it wont destroy the tank) or putting a gallon of Berrymans carb soak into the tank and leaving it for a few days, shaking it ever so often.
who has any better ideas

[chuck hahn]

Throw a galon of carb dip in it and find a way to keep it from sloshing out the filler neck.swish it around once or twice a day. Maybe give it 3 or 4 days

[Nessism]

First step, remove the petcock, fuel sending unit, and the fuel cap, and fashion some proper plugs for the openings. POR-15 sells a varnish remover sauce (Degreaser) that will work. Less caustic carb dip. If you do use carb dip, you need to allow the tank to vent otherwise it will outgas and the tank will pooch out like a balloon.

[MadJack57754]

Finally got it clean! Took many tries. First with cab dip. 1 gallon and after 4 days, it poured out like syrup. A second gallon of carb dip. It to poured out like syrup. Next did the por15 degreaser, which promptly turned to garp.
starting to get expensive, so put a gallon of denatured alcohol, sat for 2 days (swirling occasionally), dumped, then repeated twice more.
finally clean and near rust free inside. Outside tank looks like new, inside imediatly started surface rusting, so put a gallon of VP110 wit 2 ounces marvel mystery oil. Sloshed around. Will leave it sit until spring when I have time to do a better job on cleaning up the whole bike.

[slayer61]

I had great luck using vinegar on my Mrs' bike. Filled to the brim and let soak 24 hours, neutralize with baking soda, solid rinse & dry. Like magic. Be safe & enjoy your new toy!

[rphillips]

Everyone has opinions, mine is to fill as full as you can get it. I think the reason is, metal won't rust without air, the fuller it is the less metal touches any air.