Topic: Fuel tank repairs

[ryder60]

I had to get a tank for my non-Honda bike.  They are quite hard to find and the one I got has 10-15 small holes, pin size, the size of a pencil lead and one about 3X that.  I had a hard time silver soldering them because I only have a little gun.  What do folks think of fiberglassing over the soldered holes?  I'm making a trip to Alaska and don't want to develop any leaks.
I will be giving it the cream treatment as well.
Thanks.

[KingCustomCycles.com]

fiberglass will not hold up over any kind of leak.  The glass resin itself does OK but the bond to the tank will fail. I have seen many tanks where this has happened.

[TwoTired]

"Fiberglass" can be made with a wide range of resins.  Polyester is not great for metal bonding.  Neither is vinylester (I think that is a descriptor).  Some resins don't hold up against today's gas formulations.  Some resins actually develop their own waxy outer surface after curring.  These types of resins are not suitable the tank repair.

However, epoxy resins do hold up and are suitable.  As with any coating over metal, surface preparation is key.  With epoxy, you do NOT want a bond onto a smooth surface.  Such a bond tends to shear at the join particularly because of the different expansion coefficient with temperature.  You actually want a very course surface so the the resin can "bite" into the surface and grip with lots of edges.  It also has to be completely oil and contaminant free during installation.

With the proper resin and the proper application technique, epoxy resin glass is a long lasting repair.

Cheers,