RE: RC Guys Super Decathlon coming
I change out my clunk tubings every spring, and the Tygon has no issues for that long. I use the PSP aluminum Fiji water bottle cap, which allows me to get in and out of it easily. I did use the thin-walled Tygon at first, but once it was submerged in gas I found it to be SO floppy that I was worried it would flop forward too easily. It literally was like cooked spaghetti.
Tygon can harden over time. But most of us have to go in every two to three years to put a fresh set of batteries in, just to be sure. My batteries are usually buried in the same places the tubings occupy, so it just makes sense to put fresh tubings in while I'm in there. I find the Tygon to be much tougher and more resilient and resistant to chafing than the Viton outside the tank and in the airframe.
I have used the Viton, and it swelled up in the gas, though it seemed to hold okay. I remember not liking it, and switching back to Tygon. I still have the Hayes pack of Viton hanging out there.
The PSP Fiji water bottle aluminum cap has a barbed fitting inside of it, so it would be a good one to use if a barb is required, for those who use Viton.
~ Jim ~[8D]