Guest lamper2007 Posted May 4, 2007 Report Share Posted May 4, 2007 hi, if theres anyone on here that knows about four stroke motorbikes please help. i have a kawasake kx250f 2005 model, had it since new. over last month it wont kick up at all it will only bump start. ive changed spark plug and it has a good spark. theres fuel getting to the plug, but it still only kicks up when its warm and then it struggles. i just want a bit of advice because i sent my old bike to a garage to be repaired and got completley ripped off Thanks Quote Link to post Share on other sites
Guest ceredigion bull cross Posted May 4, 2007 Report Share Posted May 4, 2007 how much compression does the engine have ? for example does the kick start feel easier to press now compared with when you first bought the bike ? Quote Link to post Share on other sites
Guest lamper2007 Posted May 4, 2007 Report Share Posted May 4, 2007 how much compression does the engine have ? for example does the kick start feel easier to press now compared with when you first bought the bike ? it does feel rather easy to to turn over. when i try kicking it up it like backfires. i think it is igniting the fuel coz the exhaust gets hot but it wont start at all from cold Quote Link to post Share on other sites
Guest ceredigion bull cross Posted May 4, 2007 Report Share Posted May 4, 2007 how much compression does the engine have ? for example does the kick start feel easier to press now compared with when you first bought the bike ? it does feel rather easy to to turn over. when i try kicking it up it like backfires. i think it is igniting the fuel coz the exhaust gets hot but it wont start at all from cold sounds like you are loosing compression , i would'nt like to put money on it from this distance but from what you have said i would hazzard a guess at low compression , which is caused either by worn piston rings or cylinder bore or a carbon build up around the valve seats.. my best advice to you would be to find out from a dealer what the compression reading should be , then take the bike to a different dealer/repair shop and ask them to do a compression test. Quote Link to post Share on other sites
socks 32,253 Posted May 4, 2007 Report Share Posted May 4, 2007 SPOT ON THERE ... SOUNDS LIKE RINGS TO ME ............ Quote Link to post Share on other sites
Simoman 110 Posted May 4, 2007 Report Share Posted May 4, 2007 Had the same problem on a bike years ago and after replacing the piston rings it was fine........ Quote Link to post Share on other sites
Guest lamper2007 Posted May 4, 2007 Report Share Posted May 4, 2007 Cheers guys for the advise Quote Link to post Share on other sites
No messin 2 Posted May 4, 2007 Report Share Posted May 4, 2007 Sounds like the auto decompression cable is stuck, or the hot start cable is stuck. do you hae a decompression lever on your handlebars, if you do this should have some slack in it. I had a couple of WR's a few years ago. Worth looking at...if nothing else Quote Link to post Share on other sites
Guest lamper2007 Posted May 4, 2007 Report Share Posted May 4, 2007 Sounds like the auto decompression cable is stuck, or the hot start cable is stuck.do you hae a decompression lever on your handlebars, if you do this should have some slack in it. I had a couple of WR's a few years ago. Worth looking at...if nothing else yeah it has a decompression lever on it, ive had a few four strokes before and never had to change to rings or anything, how do i go about un sticking the cable Quote Link to post Share on other sites
No messin 2 Posted May 4, 2007 Report Share Posted May 4, 2007 Check that it is the cable first, it should be easy to see if the cable is sticking for either the hot start or the de-compressor. Make sure there is some free play in the de-compression cable/ lever other wise you are lowering the compression all of the time. if the hot start is sticking it will be letting more air through than is required, ussually when they cough and fart it is due to too much air in the fuel mixture. if the cable is not running free in the outer cable, take it off and hang it up, tape the top end to form a funnel and spray a pool of wd 40 or similar into the funnel and leave it a few hours to soak down between the outer and the cable, if this doesnt work you will need to buy a new cable Quote Link to post Share on other sites
Guest lamper2007 Posted May 4, 2007 Report Share Posted May 4, 2007 Check that it is the cable first, it should be easy to see if the cable is sticking for either the hot start or the de-compressor. Make sure there is some free play in the de-compression cable/ lever other wise you are lowering the compression all of the time. if the hot start is sticking it will be letting more air through than is required, ussually when they cough and fart it is due to too much air in the fuel mixture. if the cable is not running free in the outer cable, take it off and hang it up, tape the top end to form a funnel and spray a pool of wd 40 or similar into the funnel and leave it a few hours to soak down between the outer and the cable, if this doesnt work you will need to buy a new cable [/quote just tried, the cable seams to be working ok, pulled the rubber seal back where it joins to the carberettor and worked the lever and the cable is moving, any other ideas thanks theres a couple of mm slack in the cable at the lever end, to me on the kickstart it feels low on compression, when the bike is running it runs fine, and most ov the time it will kick up first or second time when hot. got me puzzled Quote Link to post Share on other sites
No messin 2 Posted May 4, 2007 Report Share Posted May 4, 2007 I dont know KX250F's, but I'm guessing it has an automatic decompressor and the lever on the handlebars is for the hot start. it could be that the hot start is stuck itself, inside the carb. I'm only throwing ideas around, without seeing it I cant say for sure. Quote Link to post Share on other sites
bill88 6 Posted May 4, 2007 Report Share Posted May 4, 2007 I dont know KX250F's, but I'm guessing it has an automatic decompressor and the lever on the handlebars is for the hot start.it could be that the hot start is stuck itself, inside the carb. I'm only throwing ideas around, without seeing it I cant say for sure. Took the words out my mouth mate,4 stroke motox bikes are "very" fuel sensitive.I have only known of problem's starting them when hot.If theres a moto x track anywhere near you mate get it down there,and someone wil put you right,hope you get it sorted,Bill Quote Link to post Share on other sites
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