Before doing additional petcock test, verify fuel hose isn't clogged. I think it was '95+ bikes that started using this internal filtre. Make sure it's not wadded up inside hose from being installed backwards. Even if OK, remove it
Also no need for 2 filters. First one would capture everything, so 2nd one is useless. Except it blocks flow. Make sure ONE filter is inline without drooping hose. Should be straight run from petcock without having petrol try to flow uphill.
With hose confirmed clear, now do your petcock testing
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