I'm thinking of cleaning the light rusting I can see inside the fuel tank of my 1991 CBR1000FM (UK version) using the vinegar/salt technique. My question is: do I have to remove the petcock and fuel level gauge connections or can I simply leave them attached whilst soaking?

 

I would remove them. I don't think that they would do well in salt and vinegar, or the rust that comes off the tank.

 

I'm sure it's better to remove the petcock and the fuel level sensor from the point of view of protecting them from the vinegar, but I guess I'm asking 2 other things. 1. How would I temporarily seal the holes that are left by removing the items before filling with vinegar? AND PERHAPS MORE FUNDAMENTALLY 2. Is a degree of rusting acceptable? I mean, my tank rust appears pretty superficial and certainly not deep, flakey or loose. Should the tank be absolutely scrupulously clean or is a little surface rust OK? I'm happy to clean if necessary but I'm not really into unnecessary work. Any views out there?