renegade master Posted May 9, 2017 Report Share Posted May 9, 2017 Hi Guys, My 1998 txt 270 is cutting out whn the choke is pushed in, when the choke is out it runs fine! any ideas? I whipped off the carb and cleaned it, eveything in there seemed ok! i checked the manafold intake rubbers and they look ok-ish! i check ed spark plug too and it was fine, put bike back togeather again and still the same way. Quote Link to comment Share on other sites More sharing options...
goudrons Posted May 9, 2017 Report Share Posted May 9, 2017 Check the carb again, sounds like the pilot jet is blocked. Quote Link to comment Share on other sites More sharing options...
renegade master Posted May 9, 2017 Author Report Share Posted May 9, 2017 Ok I will check carb again tomorrow and specifically look for the pilot! thanks for your input, I will post up results tomorrow Quote Link to comment Share on other sites More sharing options...
goudrons Posted May 10, 2017 Report Share Posted May 10, 2017 It's common for a blocked pilot jet if they'll start and run on choke, but stall without choke. Though small air leaks can cause the same sort of symptoms but you usually have difficulty starting and a bouncing or screaming idle when they do start. Unscrew the pilot (smallest jet), hold it up to the light and peer through it, you should see if it's blocked. Modern fuel goes stale very quickly and can leave a green gunk in the float bowl which tends to gum everything up, particularly the pilot jet and the float bowls inlet valve and seat. (when the inlet valve gums up they can stick open and pour fuel out of the carb everywhere if you're lucky, if you're not, raw fuel will pour right through the carb and into the crankcase) Best to always drain the float bowl if leaving the bike for more than a week. (drain means undo the bottom of the float bowl, not turn off the fuel and run until it runs dry!) Quote Link to comment Share on other sites More sharing options...
renegade master Posted May 12, 2017 Author Report Share Posted May 12, 2017 Ok checked the carb again, stripped it down and blow out the main jet and all the other intake holes in the carb, i took out the main jet and it was clear, i robbed the in take maifoild from another bike i had and it had no stress cracks in it so i thought that would help too, also i put fresh petrol mix in to the tank, and started it, ...... this time the bike now reves up on full choke and the throttle is not responding right, as when you reve it up it stays high on the reves and the only way to get it back down is to put it in to gear and let out the clutch! ok turn choke off the bike dies away! so heres is the odd part!,,,,,,,, start bike on full choke and drive it for 5 mins then turn choke off bike stays running at idle, but pull the throttle back and at bottom end there a bad flat spot then bike reves up and takes its time to return to idle? while driving the bike like this it seems not too bad but its lost most of its bottom end grunt and it wont start with out full choke on? I am not sure now where to look at next? probably best to rob a another carb of the spare bike i have and then see what happens? Quote Link to comment Share on other sites More sharing options...
renegade master Posted May 13, 2017 Author Report Share Posted May 13, 2017 Ok up date on the problem, after re thinking, we checked the plug again and it had signs of running lean, we whipped out a nearly new plug from one of the other bikes and tryed it, the bike started up stright away and instantly you could hear the difference! after a min adjusting the air mixture and tick over screws on the side of the carb the bike was running fine again, well better than fine! it even sounded really nice and quite! changing the plug made a world of difference! this problem must have been due to old/bad/stale fuel mix i will monitor the the plug after a good spin just to keep an eye on it, but i pritty much think thats that solved! Quote Link to comment Share on other sites More sharing options...
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