2008 ktm 450sxf 40 hours
Ran like a champ never any issues
It's my buddies bike and he was literally moving to Fla today so last night he drains the tank and STARTED the bike and let the carb run out of fuel while bike was running!
Another buddy wanted to buy it Today< we refilled with fresh fuel< bike will not start. new plug,checked valves(good), Battery is jumped to my truck so cranking pretty good. jetting is stock i beleive, i know for sure pilot-45 start jet 85. I took them out to make sure they werent gummed up. Good spark and  Compression seems good(hand over pipe and it feels strong),i pull the air boot and cover carb while cranking and it puts a lot of suction on to my palm. i dont have a compression tester. it simply ran ot of fuel at idle and i'm F'N stumped!!!!! any help please. will not start!!!!!

open valve cock

Havingfun, on 31 May 2012 - 12:44 PM, said:

Hey Knucklehead whats a valve cock? do you mean petcock? it's on.Thanks for the input. Jus messin with ya.

I have had similar problems with my '08 450 SXF, seems like every time I go to the track it cost me a small fortune! runs great, shut it down and park it in the shop after a moto with no problems! then when I go to start it up again a few days later I find something serious went wrong! seems that with this year of bike there were many engineering issues! from crap clutch baskets coming apart and fouling the oil pumps with bits of aluminum to faulty crap stock oil pumps in the first place! I am the original owner of my 2008 SXF and have completely rebuilt the engine twice at a cost of around 3k each time! this is not including the constant repairs and parts along the way! 3 pistons, 2 cylinders, 4 clutch assemblies, had to replace oil pumps twice outside of the rebuilds, new cams and timing chain tensioner not long ago, spk plg tube seals, new coil this season, new plug every fuggin 3hrs! and the list goes on and on and on! and I am now looking at replacing  g the crank and bottom end barrings lmfaro! I could have bought a brand new bike with the money I have spent on repairs on this '08 !!!

this all being said there is one thing I have to say, the bike is a monster! its a "nuclear powered hole shot machine!"  the power it produces simply can not be touched by any jap bike (stock!) the suspension rockz! it is commonly referred to as the formula 1 of motocross!! so... with the performance and power of this bike comes a heavier more costly maintenance bill! this is not a trail bike! its a race bike!

think you need to look up both valves.

iMOTO189, on 31 May 2012 - 01:38 PM, said:

Edited by Havingfun, 03 June 2012 - 12:14 PM.

I have a buddy that sold his 08 had over 200hrs on stock bike all MX bought it used..  no issues.

UglyGrunt, on 03 June 2012 - 08:57 AM, said:

Man that sucks!!!  For everyone else's sake that owns this bike, I hope you just got a lemon.

MAX!!!