Better gas tank???

gnarlshark · #1 01-11-2009, 11:47 PM

I am still building my bike and while test fitting the gas tank one of the bolts snapped about 1/4 inch from the tank. I can't see of any way to easily repair this so I guess I have to order a new one. Does anyone make a higher quality tank or are they all pretty much the same? the tank I have also came with some rust in it. I planned to put a liner in it but I don't want to spend money ($30+) on that unless I have a tank that will last. Please help.

**2door** · #2 01-12-2009, 12:05 AM

Quote:

Originally Posted by gnarlshark

I am still building my bike and while test fitting the gas tank one of the bolts snapped about 1/4 inch from the tank. I can't see of any way to easily repair this so I guess I have to order a new one. Does anyone make a higher quality tank or are they all pretty much the same? the tank I have also came with some rust in it. I planned to put a liner in it but I don't want to spend money ($30+) on that unless I have a tank that will last. Please help.

Many of the tanks come with rust...it's part of the package. Drop in a handfull of pea gravel and shake the heck out of it then flush it with hot water and blow dry it with compressed air before you install the fuel petcock. As for repairing the broken stud...it can be done but you need the services of a very good welder. New tanks are available but I'm afraid you're going to find the quality pretty much universal. As for twisting off the stud, this is a problem encountered by many first time builders and not just with the tank. Do not, do not, overtighten any nut or bolt on your engine, chain tensioner or rear sprocket. If it has a lock washer tighten it just enough to flatten the washer then just a slight twist more...very slight. Use Loctite on everything and don't listen to the advice that you need to retorque every time you ride. That's how bolts, screws, and studs get stripped or broken. Check thatsdax.com for a new tank but you might want to seek the advice of a local professional welder before you invest in a new fuel tank. Hope this helps.
Tom

w31john · #3 01-12-2009, 12:15 AM

I cut off all the threads and weld on a new 1/4-20 hex bolt.
I do that to all of the tanks i use.

Retmachinist · #4 01-12-2009, 07:39 AM

Quote:

Originally Posted by gnarlshark

I am still building my bike and while test fitting the gas tank one of the bolts snapped about 1/4 inch from the tank. I can't see of any way to easily repair this so I guess I have to order a new one. Does anyone make a higher quality tank or are they all pretty much the same? the tank I have also came with some rust in it. I planned to put a liner in it but I don't want to spend money ($30+) on that unless I have a tank that will last. Please help.

Do you still have 1/4 inch of threads on the broken stud? If so it would be very easy to make a 5MM extension coupling. That would save you $30 bucks. It would be nice if they would make those studs 6MM, would save a lot of people a lot of problems. Let me know if you need some help.

John

**Bikeguy Joe** · #5 01-12-2009, 10:45 AM

....or, use the last 1/4" of thread and make a longer strap for that mount.

Furnace duct hanger strap works and is cheap.

offroad · #6 01-12-2009, 01:29 PM

I saw an engine with the fuel tank behind the rider seat. Looks like a bike bag. Seems like a smart way to do the tank, and have a little more stealth. My concern is stealth. Having enough covers to not let anyone know you have an engine, when the engine is turned off. Cover it with a black zipper bag (canvas, etc.) and let people think it is just another bike bag, on the bike. Wonder if I could get my local bus to carry the bike, not knowing what it is they are carrying.

The tank is on a bike for the front page of SICK BIKE PARTS.

WOLF IV · #7 01-14-2009, 01:25 AM

just an alternative option ....im building one from a r/c plane 32oz. tank that has the correct dementions to fit insid my dummy tank, . ill try to post a pic./. im an engineer, but dont do much drawing when it comes to fabricating... but sometimes ill put iit on paper for #'s only...

offroad · #8 01-14-2009, 11:55 AM

are gas tanks required to have some kind of safety expansion valve, for if they are getting hot and creating internal pressure?

**2door** · #9 01-14-2009, 12:11 PM

Quote:

Originally Posted by WOLF IV

just an alternative option ....im building one from a r/c plane 32oz. tank that has the correct dementions to fit insid my dummy tank, . ill try to post a pic./. im an engineer, but dont do much drawing when it comes to fabricating... but sometimes ill put iit on paper for #'s only...

Wolf,
I'm intrigued with your idea. I'm also familar with model airplane fuel tanks and I'm curious how you fill your tank. I'm currently looking for an old cruiser, with a tank, and I want to make the tank functional. The airplane tank idea is a good one but knowing how I have to fill my plane's tanks, with an electric fuel pump and 3/16" hose, that seems to make refueling a bike quite a process and almost impossible out on the road. Just asking.
Tom

Retmachinist · #10 01-14-2009, 12:50 PM

Quote:

Originally Posted by offroad

are gas tanks required to have some kind of safety expansion valve, for if they are getting hot and creating internal pressure?

Since these are gravity feed systems it will definitly have to be vented with a vented cap or whatever. Don't think just a expansion valve or check would work.

John