AlGeorge

I took the sparks out today and they were pretty sooty, so i cleaned them up and put them back with a drop of fuel in the cylinders and it started! it was ticking over nicely so i took it out for a test ride and that went fine, but after about 20 minutes i got it back, switched the engine off and tried to start it up again (just to check it was still good) and nothing! same as before really, only now it JUST starts to catch, but don't reach 2000 revs before guttering out.

Hey guys, long-time-lurker first-time-poster here! So, I've been working on my xs250 over the past week and now i cant get the engine to start up... It wont fire up, just whirs when i push the start button and I've had no luck with the kickstart either. Basically, to sum up what i've done to it since it was last working: it had broken down on me while i was out on a ride (the vacuum tube kept popping off the tob of the carb inlet and the engine was heating up like crazy, but after much kickstarting i managed to get the thing home with the petcock set to prime) so i decided to check out what was going on down there. I popped out the carbs and checked them over, checked the floats were ok, idle screws, no gunk etc. and they were fine. so as i was putting them back, i noticed a HUGE hole in the airbox that looked as if someone had leant a hot poker up against it (warped melted plastic, which had drooped into the airbox and hardened up and seemed as if it had been sitting there for many-a-year). I patched that up with some aluminium tape. I also noticed my petcock was dripping fuel even when it was disconnected, so i swapped that out with a spare i had lying around. After putting everything back in place, i tried starting the engine and nothing. Wouldn't budge. Just the started motor whirring. After much deliberation and consulting the internet, I decided the best option would be to swap out the condensor so I ordered a replacement which I fit today and lo-and-behold: NOTHING. Same story as ever. Has anyone had/got anything like this? I'm just running out of ideas.