Why wont my dirt bike start?

Question

I have a 2005 KTM 85sx. I bought it used and have only ran it a few times. But, until now i have had no trouble at all. I had taken the packing out to replace and had run it for a few days without it. I replaced the packing. But when I went to start it nothing happens. I checked the plug has good spark, I replaced the main jet and when i checked the float bowl in the carb was full. Im not sure why it wont start. Any advice???

Answer 1

i'm just making an educated guess as i've never messed with packing before... is it possible you packed too much or packed it in to tight?

could easily be why the bike won't start if the exhaust isn't flowing as trouble free as it's meant to.

if you take the packing back out and it cranks right up afterwards, you know this was the problem.

well, are you sure you messed with nothing else but the packing? are you sure the fuelcock is on? i've made that mistake so many times thinking there was a problem with my bike only to realize i forgot ot turn it on...

if they're dry it means gas is not getting through somewhere.... follow your fuel hose coming off the gas tank to make sure it's not kinked.... if not, check to make sure the hose isn't obstructed (remove it from the carb and turn on the fuel c**k is probably the easiest way, if gas comes pouring out it's fine... if it only drips out, you got a problem either with your fuel c**k or the gas line itsself

OK, now there's something to work on, sounds like you didn't put something back together right.... did you have to adjust your needle after you removed the old packing and rode it? if not, are you sure you have the needle set in the right position? like is the lil washer/clip in the same notch as it was on your old one?

your manual should tell you.... all bikes are diffrent....

if not, just play with the diffrent settings.... moving it up higher reduces the flow, and moving it lower increases it... if it's at the top notch i'd be willing to bet money this is your problem.

d**n, man i'm running out of ideas..... ok kick your bike over a  few times and immediately pull the plug... is it still completely dry? err.. n/m you did that, give me a bit to think...

did you wash the bike about the time it stopped working by any chance? i'm really starting to grasp at straws here... could you possibly get a new spark plug and try again? fouled spark plugs will mimic fuel delivery problems.... what color is your spark plug? it should be a very even golden brown color.... or is it just that bone dry?

yeah that's what i keep coming back to but nothing i've thought of to check yet has produced any results....

can you recall what the spark plug you first took out looked like? since we're working with new spark plugs we've lost precious 'evidence'... spark plugs can help identify a number of problems

here's how lost i am, i've turned to searching the net for anything i can find lol...

"Even if the spark LOOKS good, it still may be arcing along the wrong path or not pruducing a hot enough spark - put a new plug in there!  Next, check the coil and CDI.  You are getting some spark, so I doubt it's these, but they are worth checking. Also, check the fuel filter - it's located inside the fuel on/off lever at the tank.  Finally, check your carb vent lines - you may be getting fuel, but if the vent lines are clogged the bike won't run.   "

obviously the spark plug isn't the problem (unless it's gapped incorrectly, did you check?) but the rest is a good idea to check.

if they were black that could mean oil is leaking... probably due to a worn gasket or valve.... do you know how to check? this causes hard starting, and in some cases, the inability to start