so I'm riding my 03 kfx today, and i roll the machine. No big deal, i didnt get hurt, bars just rotated down a little. HERES THE KICKER:
I start it up, and it sounds weird, like a nasty air leak, or the filter is off. i shut it off and look for the carb boot to be off or something. nothing wrong, no tears, nothing slipped off.
start machine again and try to rev it out, it acts as if the reverse rev limiter is on.
I bring it to the garage, i check the fuel system, thats good, go thru the wiring with a fine tooth comb, that seems good. even checked the choke to make sure it wasnt bound up.
so i check the spark plug, its a little rusty(old) and really carboned up. I wire brush it clean and reinsert. Now the machine will no longer start and acts like it has little compresion.
so i pop the head to check the valves. first thing i notice is slight blowby from one of the valves and timing APPEARS to be way off. can anyone verify where the stock timing marks are supposed to go?? my gears have 2 arrows each in a 90degree L shape and white paint which appears to line up with those marks but they are 30 degrees off at TDC. so i mark the timing i have with blue paint, and switch it to white marks. machine sounds WAY better now turning over, but still refuses to fire. I am going to buy a spark plug tommorow and HOPE it just jumped time and the plug went bad by me cleaning it. anyone have any suggestions???

 

Wow. Hmmmmm. Well lets see. I'll just think out loud for a bit.
It takes 3 things for an engine to run. Fuel, spark, and compression.
Did you see if it's getting spark? Pull the plug and lay it on the head and turn it over. Spark? Buy a new one and install it anyway if the plug is that old.

Does the pipe smell like raw fuel? Could have hung the floats when it was on it's top? Smell the oil too. If you hear an air leak you might want to look over the boot again. My 700 has all sorts of hoses coming off of it. I don't know if the 400 has the same set-up or not. You might want to shoot some starting fluid around the boot while cranking the engine. It will catch if you have a leak and do this.

If it sounds like it has little compression, I will take your word for it. Take a compression and see what you get. How long was it on it's top? If oil got on top of the piston and you turned it over that's not good. It might have been hydro locked and you bent or broke something?

I can't help you with the timing because I have the big block (700) not the small block.

Let us know what you find when you get it running.

 

***checked spark had that and swapped plug****

well its not good news, but i know whats wrong.
Double checked timing against my buddies, and yes it jumped almost 30 degrees.
removed the head and the intake valves had hit the piston, no marks on valves, but slight imprint on piston from it, and altho the valves look fine, a leakdown test with starting fluid proves that the 2 intakes are leaking bad.
so WHY it did it is beyond me, timing chain stretch maybe, but now I am looking at building a monster. :-)
anyone had any problems with wiseco stock bore high compression or ATHENA 435 bb kit?? those are my 2 options, with a new valvetrain and some cams.

 

I got a namura big bore kit for my 03 kfx 400 (same motor) and was a big help and ive had it for about 5 months and it was nice.

(03 kfx400 440 big bore kit sedona tires pro flo power kit bill balance exhaust pro taper fst bars) comong soon- stsge 1 jot cams 4mm stroker cramk houser a arms dura nlue axel podercoating the frame candy blue)

 

Put on the Athena 434 kit two years ago. Best thing to do along with cams and the FCR carb.

 

This is a thread from 6 yrs ago-I would guess that he has it taken care of by now!!