Well I think I fixed the short on Mike's CB750K2 Cafe Racer today, but fell into a fit of depression when I realised that the oil leak will probably require me lifting the head, so I took my Sportster for a ride to cheer me up. I've been messing with the jetting on the Mikuni flat slide race carb I installed a few months ago, from new it felt lean so I bored the main jet from 160 to 205 (only because I only had one jet drill bigger than 160) and it actually ran pretty well, but I'd since bought some new jet drills, so I bored a 165 out to 180, and adjusted the idle mixture.
I also checked the fuel tap's flow, as in the past it's felt like it was running lean at high RPM, to the point where it'd tap out at 5K RPM, (approx 90 MPH) and I was actually thinking about buying a Pingel petcock, but after filling a 5 litre drum in only a couple of minutes I decided that there was nothing wrong with the OEM tap.
Anyhoo, I took it for a ride, and a few miles down the road, it conked out. Fcuk. I rolled to the side of the road, and checked the fuel level, even though I knew it was half full. I turned the fuel tap lever to "Reserve", turned the key, hit the button, and it fired right up. Hmmnn, weird. I rode another 3 or 4 miles, and it did it again! Fcuk!
Same same, checked the fuel level, played with the fuel tap, hit the button and away I went. Four or 5 miles down the road, I could feel it dying again, so I reached down and loosened the fuel tank cap, and away it went! Blocked fuel cap breather! I rode back home with the cap loose (no issue, it didn't miss a beat) and when I got home I replaced the cap with a new "Drag Specialties" lockable cap I'd bought a few weeks ago, and took off again. No issues for the rest of my ride, so I was glad that it wasn't something more serious. Woohoo!