My honda cbr 600 is struggling as if it keeps running out of petrol. whats happening?? Having a similar problem. I've had a 1996 CBR600F (50 000km) for about 14 trouble free months until recently. The bike has generally been riden 5 of 6 days a week in this time. 2 weeks ago, travelling at about 60k/h the bike started behaving like it was running out of fuel. Bike gave up after about 400m of coughing and spluttering. I drained the battery trying to restart but was able to roll-start the bike after a little persuasion. Then had 2 30min trips with the bike being its normal self. After about 4hrs tried to start it again and bike would crank (until the battery died again) but would not start. Dropped the bike off at the mechanic (started fine after charging battery and didn't play up for the week that they had it). They checked the battery is getting and retaining charge and cleaned the fuel pump. Picked the bike up and after 5-10 mins riding had to call them to pick the bike up after it stopped again. They got it back to the workshop and it started first go. Another week later the bike had played up on him on a test ride and the fuel pump was replaced after it looked like an intermittent problem. Mechanic took the bike for a lengthy ride with no problems. Picked the bike up and riding home, after about 5 mins, doing about 100k/h bike played up again - like it was running out of fuel. Dropped to 4th gear and left the clutch engaged at which time the engine stopped. Released the clutch and eventually the engine started running on its own, although this took a lot longer than a normal roll start - like it was running out of fuel but being forced to operate. Got the bike home with a few more instances of it 'running rough' but keeping the revs high (using clucth to keep at min 3500rpm) seemed to keep it from dying. Main problem is that it doesn't seem to matter if the bike has been running or not, and it will start after playing up given the right amount of time, although this is inconsistent (can be 20mins or 2 days). I'm not sure if the fuel filter was replaced when the fuel pump was, I don't think so though. I'm thinking this could be either of 3 things; dodgy fuel, fuel filter or carby problem. After forking out for the fuel pump I'd like to look at the most likely cause first. I'm pretty new to bike mechanics so any suggestions either on these 3 things or anything else would be greatly appreciated. Sorry for the lengthy description - trying to give all info and answer questions before they're asked.