Evening i have found a couple of small holes in my 1991 K-100 LT petrol tank. 
I know from looking for a replacement there are many different tanks. 
Could i ask if anyone know what tank should fit my bike and if any other model’s tanks will fit. 
Thanks in advance. 
Thanks 
Barnie68

Before you outlay the money for a new tank, consider other options. You will need to assess how bad the damage is. My preferred repair would be to have the holes welded. A good welder experienced in TIG welding should be able to assess the damage and give you a quote. There are also chemical coating products that can mixed and added to the tank to provide a fuel proof lining. The other solution is to use a fuel proof putty. 
Regards Martin.

This stuff is what I use to fix fuel tanks.It holds up to all fuels and seals small pin holes and leaking joints. It's an epoxy of some sort.
Fuel Tank Sealer

Thanks martin 
My friend has been back on the phone both side have holes. We are going to try get it welded first but i thought i would ask if the welding dont work. Sadly my mate does not have a mig he has just bought a nice very good welder just not a mig one. 
We will look into it. 
Thanks
Barnie68 

Hi yamaguzzi
I have looked up the sealer but due to that silly boat captain they have no supplies till mid june but i will try and find some 
Cheers 
Barnie68 

TIG is the preferred method of welding aluminium, you can also use oxy/acetylene welding with aluminium solder sticks. Due to the tank being pretty thin unless you know what your doing it's pretty easy to blow holes in it. I'd probably try and find a specialist welder.
Regards Martin.

Hi martin 
my friend is going to try mending it before we give up and get someone else look at it. 
If it cant be done i will have to buy another one but fingers crossed as there are so many tanks we have no idea wot one we would have to use. 
Thanks for your advice and hopefully it will work. 
Stay safe
Barnie68

Halfords do a fuel tank repair putty.
Regards Martin.

Thanks martin i will let my mate know as he has the bike and i wont be seeing him for a couple of weeks. 
Thanks again

Barnie68 wrote:Evening i have found a couple of small holes in my 1991 K-100 LT petrol tank. 
I know from looking for a replacement there are many different tanks. 
Could i ask if anyone know what tank should fit my bike and if any other model’s tanks will fit. 
Thanks in advance. 
Thanks 
Barnie68

Go HERE
Note the part number, item 1
Click on that number
Note the model Katalogues it's in
Click on those Katalogues
Determine which models share the tank you need
Don't get fooled by the list of models, actually click on the the various models in the chain
Too easy

Hi mate SLOSH tank sealant is readily available in UK same  type of product as Mr Y suggested. Very good feed back as well 

Thanks moriarti
I have ordered tank putty already which we are going to try. 
Thanks again. 
Barnie68

Halfords tank putty works fine. I've sealed two tanks with that stuff - just follow the instructions and make sure the area is scrupulously clean after you've roughed it up.