NOPE, There are none :(. I searched all over and called Everyone!!
I talked to a guy that builds alot of one off carbon fiber tanks and he has done work for IMS. He said that they can be expanded. Well I tried it. I am on the 3rd try as I do not want to ruin it. You need to get the tanks at 325-350 degrees then the plastic is pliable.
Clean it well first.
I filled it 3/4 of the way with Boiling water. That got it to 175-185.
I used a heat gun to soften the area that I wanted to expand. I then applied air pressure <5 lbs to the tank. I would rotate the tank to allow expanding one area at a time. The water would cool and provide even support for the tank as you worked on it. MAKE SURE you make a jig to bolf the tank to. As it will never fit back on the bike.
Once done it shrinks back some but the hotter you get it the more it will stay.
1st try I went from 1 gal+1qt stock to 1 gal 2.5 qts settled back to 1 gal 2 qts
2nd try went to 1gal 3.5 qts and settled back to 1 gal 2.75 qts.
I had it to 2 gallons but as it cools and you put fuel in it. The bugger shrinks some.
We want the capacity for GNCC's and Junior Enduros. Last years bike as a 85cc, junior would get 21-22 miles and it would be on vapors with a stock tank normally that was 65-75 minutes of riding. This year the bike is a Eric Gorr 100 kitted RM85. Same basic jetting. Last week was a test on a fast course: 1 parade lap and 6 race laps for a total of 25 miles in approx 76 minutes. We had 14 ounces of fuel left in the tank. So we need a tad more or atleast enough so I can get him for a fast splash and go....
WOW! That sounds like a lot of work just to get a gas tank bigger. I am sorry but i don't have any other options for you to try. I say, if your serious enough about it, go for it. If you mess up, that is worth less than if there were an aftermarket tank anyways.
Do u think that u could maybe modify a tank from a bigger big say a Rm125 or Rm250. Would there be anyway to make special mouting brackets and not have it interfere w/ anything else?
Heated it again/ aired it up/ cooled it in the fridge over night and it stayed :) Need graphics now....
We are at the limit of distorting the seat mounting and fit. 1.84 gallons. (236-240 ounces of fuel it holds after bolting on. Stock would hold almost 165 ounces. 1.25 gallons. So we should get close to 1hr 20 -1hr 30 minutes of hard riding. We will try it this weekend at the GNCC.