Failed tank liner

I have been having intermittent problems with fuel starvation. The effect of this has been running on two cylinders, cutting out, then restarting after a few minutes at the side of the road. I know it is a fuel starvation problem because the bike would run on either cylinders 1 and 2 or 3 and 4: both combinations are served by both coils so coil failure could be responsible. I have had trouble with one or other of the petrol pipes doubling over and cutting off the supply to the left or right pair of carbs. Also, I have fitted two clear fuel filters into the petrol pipes and so I could see them empty of fuel when the bike has come to a stop, and then gradually refill. I figured that flakes of the liner were probably wrapping themselves around the filter that is integral with the petrol tap, thereby restricting the flow of petrol through to the carburettors. I had previously had a go at removing all the loose liner from my petrol tank, including fishing in it with a spring-loaded grabber tool and then draining it entirely. I managed to get a lot out and thought the remainder was sound. However, the return of the starvation problem suggested otherwise. I was pretty sure that once again the failed liner was at the root of the problem so I decided to try getting some more of it out.

I used my grabber tool again and soon found it wasn't hard to fish out large flakes of the liner that had come loose inside the tank and was floating about in the petrol supply.

In the photo above, you can see the size of these flakes in relation to the petrol filler.

So after about 30 minutes of work, I managed to get a considerable amount more of the failed liner out of the tank. I'm pretty sure there aren't any other large flakes there right now but I'm equally sure more will come looses and foul the fuel outlet once again.