KTM-Lunatic

~SPONSOR~
Mar 2, 2000
83
0
As usual when everything appears to be going good something happens, Tonite i was sitting in my garage when i smelled gas after looking around for about 15 min. I found the problem. On my son yz 80 there is a small crack in the bottom of the tank .What my question is is there a cheaper way to fix this than to replace the tank. Money flow at this time is very slow :( due to a street bike accident back in Jan. that has put me on the disabled list
 

glenncal1

Member
May 24, 2001
40
0
KTM-L, I used a product called Creme to seal the tank, so far it has worked very well. For just the tank sealer it is about $13-15, call around to some of the shops in your area they should carry it. You might try some of the Auto Parts places too.

Jim
 

Papakeith

COTT Champ Emeritus
Damn Yankees
Aug 31, 2000
6,695
50
RI
There is a process called plastic welding that might be just the thing you are looking for. There was a thread on the topic awile ago. But, I think it was before the big DRN changeover.
 

LB400

Member
Apr 9, 2001
59
0
Papakeith has a good idea!

Why not try your local ski shop for someone who works on plastic ski boots. Most large shops will have a plastic welder (or know someone who does), and I don't see any reason why it wouldn't work on a bike tank.
 

Jon K.

~SPONSOR~
Mar 26, 2001
1,354
4
Welding is the only option. Nothing, repeat NOTHING will stick to the plastic. Ask yourself first, though, why is it cracked? Is it brittle for some reason? If so, consider the cost of a burned up motorcycle and maybe even an injury if the thing leaks during operation! You might pound on it with a fist or a fence post to see if it is just going to fall apart again.
At a race once upon a time my wifes' tank spontaniously sprung a leak and I heated a coathanger to melt the crack back together by sort of stirring the plastic with the hot wire. She finished the race without exploding into a huge fireball. . . . We bought a new tank imediately. . . . don't really want to blow up the wife. . . . .er. . . well. . . not really !!!
Glenncal, was that a plastic tank? I have used Creme on steel tanks with some success, but never tried it on plastic. I am skeptical.
I bet a ski shop is hard to find in Brandon, Mississippi, but look in the yellow pages under "plastic" and you will probably find a listing for a specialty shop.
 
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theshiftkid99

Posts Too Much
Member
Mar 21, 2001
32
0
Well JBweld worked for my YZ!!! It comes in a little tube, and it sticks very well, and if you go to the webpage in the tesimonials section there is multiple people who say " it saved a very expensive motorcycle gas tank"!!
good luck:D
 

Jon K.

~SPONSOR~
Mar 26, 2001
1,354
4
JB weld or many other epoxies work quite well on STEEL . Plastic is a whole nother thing. Tread carefully!
 

Jon K.

~SPONSOR~
Mar 26, 2001
1,354
4
Hey KTM-Lunatic; Please check your PM.
 

DENNY

Member
Nov 24, 1999
218
0
I have repaired 3 tanks with a wide tipped soldering iron with great results. In 1989 a stick punctured my KTM tank and as far as I know the owner is still using the same tank.
 

theshiftkid99

Posts Too Much
Member
Mar 21, 2001
32
0
I know JB is for steel but is also for plastic, like I said I had a hole drilled though my gas tank and JB weld fixed it , so I know with experience:D
 

DougRoost

~SPONSOR~
May 3, 2001
720
0
Any good body repair shop will have a plastic welder. So many body parts on cars nowadays are plastic they have to. I've only visited one so far re: my cracked gas tank, but he told me not to bother. The owner pointed to his son's Yamaha in the corner and said they plastic welded its gas tank and it still leaks.
 

Jon K.

~SPONSOR~
Mar 26, 2001
1,354
4
Wow!! How do you find a post from July anyhoo?
 

DougRoost

~SPONSOR~
May 3, 2001
720
0
I try to be a good netizen and do a search before blindly posting. Turns out there were quite a few threads on cracked gas tanks! Unfortunately, the news is not too encouraging and it's probably not worth risking the bike to fire.
 

bake

Member
Sep 20, 2001
156
0
When mine started to split I took a local mechanic's advice and welded it with a good ole Weller soldering iron (use the flat tip) then filled the repair
with a plastic i found by (experimentation) that literally welder. Really at this point you don't have muck to loose.
 

DougRoost

~SPONSOR~
May 3, 2001
720
0
Yes, plastic welding would have been my next choice, though the body shop I took it to said it wouldn't work. The real problem would be if the repair let go while you were riding. Gasoline dripping down on a hot engine below your crotch -- not a nice thought. Luckily Kawi comp'ed me on a new tank!
 

Yamamoto

Uhhh...
Apr 3, 2001
349
0
First off

J-B weld does not flex!!!!!

I Have fixed an old tank on a 83 yz125 and what I did was obtain an old piece plastic like an old side cover or fender, well heck you can even just take a piece off the rear fender to use.

Take the tank off and CLEAN it good wash out and fuel!
Now focus on the crack and clean it with alachol, after it dries heat up a butter knife or any sharp blade that will fit in the crack. duct tape may come in handy to avoid your hands getting burned by wraping the handle.

Take the piece of plastic and melt it very slowly in a (shhhh dont tell my wife) very large spoon or ladle, now with the crack clean and pre melted to assure that there are no oil residues left in the cracked area you can then (this takes two people) at the same time reheat the crack and pour the melted plastic into it using the HOT butter knife to apply pressure to the cracked area.

The hot butter knive will help bond the two plastics together.


I reccomend using two knive so that you will have a hot knife ready if you need it.

oops I fixed a 94 YZ125 using 83 yz125 plastic.
 
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