I have a 73 Sporty that I have owned for a little over a year and have an issue that I need help with please. The bike will be running great for 10-15 minutes and then it shows all signs of running out of fuel when it sputters and then shuts off on me. Most of the time I can re-kick her and she starts right back up but then will repeat the above anytime within the next 5-10 minutes. Of course, I have checked fuel and it has roughly half a tank.

I had a local guy look at it and he thought it was a vacuum issue with the gas caps so he told me to loosen the caps and that seemed to work for roughly an hour of net riding the last week but is repeating the issue again. this has gotten very frustrating so any help is much appreciated. Thanks in advance.

 

These symptoms are a classic sign of a clogged fuel filter.

The normal fuel filter is in the tank, attached to the petcock. To remove it you drain the tank, unscrew the petcock, remove and clean the filter, and re-install everything. If the tank drains slowly that would confirm this diagnosis.

If you have an external filter there are two considerations. First the filter must be designed for use on a motorcycle gravity feed fuel system. There are no automotive fuel filters that will work - they all expect a fuel pump. Second, it is a bad idea to run both the internal and external filters as this can slow down fuel flow.

Check this out. If this does not solve it let us know and we will come up with some other ideas.