Hi, The fuel filler on my 2005 999 seems a little "loose" when I close it (doesn't feel like it's sealing properly) and I wondered if I can adjust the 2 screws on the spring-loaded "diaphragm" shown in the attached image? Both screws were firmly screwed in but if I release them a little, there is more "give" on the spring and this seems to provide a better seal. I can't see anything about an adjustment anywhere, so thought I'd see if anyone here can confirm my theory?
Thanks for the suggestions, do you know which part I can replace i.e. just the o-ring (which i assume has gone brittle after 20 years) or is it the entire "diaphragm" unit and do you know the relevant part number?
I am testing whether ChatGPT can reliably diagnose faults. A bit of an update. https://chatgpt.com/share/69dfd6f4-2680-8329-b665-0ffcc4a20cc7
Thanks but I think ChatGPT is hallucinating again, the part number it's suggesting is a completely different item to the one shown in the photo
All the 749/999 fuel caps feel "springy" when you push down on them to be fair. Always have done. I wouldn't loosen those screws. If they work out and fall in the tank, so will the parts they hold in place. I don't think you have an issue.
Probably not an issue as Nelly says, but it would be worth removing the screws and checking the spring behind. I suggest removing the assembly and doing it somewhere where nothing can drop in to the tank. A surprising amount of corrosion can build up in there, if the spring has been weakened or snapped it will be loose. The parts don't appear to be available separately, but remember if buying used off Ebay etc then the shared early Multistrada parts like the fuel filler and rear light set up can be cheaper.
