I'm sorry to hear about your friend. With your experience do you have or know of a cap that doesn't leak, even a bit ? Both my bike and my wifes have a bit of fuel mixture around the cap and on the tank that we wipe off constantly to keep the paint looking good for as long as we can. It's not alot, just a bit, enough to be annoying ! I think we tried everything we could think of. Thanks in advance.