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cant start my 250sx- how do i fix it?

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I just got a new second-hand bike (with 5 hours on it) and because i wanted to have the bike in 'tip-top' condition i decided to lube the throttle cable, but i did it with some wd-40 look alike, not 2-stroke oil because i didnt realise that the lube would go into the carby.

also, i just replaced the grips and was twisting the throttle a fair bit a few days ago so it was probably flooded.

would this be why it wont start now? and how do i fix it?

it started first kick before, but now it doesnt even have a hint of starting and ive swapped spark plugs, that didnt fix it.

what should i do? fuel is on, but-plug out, choke on, no throttle for a few times with no luck then full throttle then no throttle, you name it, it didnt work.

so yeah, how can i fix this?

thanks, Mike. :ride:

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Just for thought, I left my CR in the trailer with the gas on for about a week! I guess what happened is from the gravity pressure, it kept on pushing fuel into my cylinder causing it to "load up" witch caused weird stuff. Did you leave the gas on? try lookin for the simple stuff too sometimes we over think the smallest problem mistaking it for a big one!

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i had left the gas off since i last rode it a few days ago, but turned it on like 2 mins before i first tried to start it today. the wd40 stuff wouldnt be a problem would it? say it did get burned, that wouldnt do damage right?

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Twisting the throttle on a 2-T won't flood it like a $-T with an accelerator pump, and it is unlikely the cable lube is an issue either.

First thing to check is the pull the plug, First, check to see if it is wet, as it will be wet if it is flooded. Put it back on the wire and hold the plug on the cylinder and kick it while checking for spark, it should be a nice bright blue spark. No spark. replace the plug and try for spark again. If you have spark, and the plug was dry when you pulled it, make sure you are getting fuel. Lean the bike over to about 45 degrees and see if the carb overflows. Then try kicking some more, starting with the choke on, no throttle. Still no fire, full throttle and kick a LOT, or better yet, bump start on a hill or get a tow/push.

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OK, 3 things it needs to run.. fuel, spark, and compression. Which one doesn't it have?

Pull the plug, ground it on the case somewhere, have somebody kick it over while you watch for a STRONG, BRIGHT spark. If it's weak out side the combustion chamber, it won't light the mix inside.

Next, is it getting fuel? Does the plug smell like gas after you kick it a few times? If not, that would indicate a clogged pilot jet.

Compression.. you know whether someting major enough to keep it from starting is going on when you kick it.

If no spark, your going to have to back up through your ignition system to find out where it stops.

If no gas, you probably have a clogged pilot jet. Take the carb apart and clean it thoroughly. Take both the jets out and spray them out good with carb cleaner.

The WD-40 you used had nothing to do with it, but I'd suggest getting some regular cable lube for next time.:ride:

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ok, well i checked the spark plug and it was black as, but dry (previous owner ran it at 32-1), but i swapped the spark-plug anyway with no effect.

it does have compression, just as much as its always had.

today i'll check for a spark and lean the bike over untill fuel comes out. what else?

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ok, well i checked the spark plug and it was black as, but dry (previous owner ran it at 32-1), but i swapped the spark-plug anyway with no effect.

it does have compression, just as much as its always had.

today i'll check for a spark and lean the bike over untill fuel comes out. what else?

Leaning it over just proves it's getting fuel into the float bowl, won't help a clogged pilot jet.

If it's getting spark and still won't start, your back to needing to clean the carburator.

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well the other day i stuffed up.. http://www.thumpertalk.com/forum/showthread.php?t=875311

click on the link if you want a good read on the stupidest thing i think ive ever done, but long story short the cable got ripped, so the kill switch cable leading to the earth was snapped. we soldered that and did a good job of fixing that, so now it'll turn off, but also, the lead came off the coil, so i put it back on and bam! now it works. i had to spend some time trying to start it and burn the oil out of the cylinder.

i also turned the fuel tap off and ran the bike till it died, that way there'll be no oil clogging the jets.

so i should be able to just turn the fuel on, wait a minuite and then start it straight away. :ride:

is there anything wrong with that?

thanks for the replies :ride: and im really glad i didnt have to take the carb apart haha.

Mike. :lol:

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lol heartbreaking to have this happen when youre only meant good

i'd say lay off the tip top condition stuff and just make sure its got fresh oil, clean airfilter and a lubed chain

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