400ex won't run

[hsbarker81]

I'm looking to purchase a 1999 400ex for next to nothing.

The guy says it has fire and is getting fuel, but will not run.

My first assumption is a timing issue?

Anyone have any input or an idea of what my worst case scenario is time and money?

thanks,
harley

[hsbarker81]

ttt

hellllllllllllllllp ;)

[QuadManiac]

If it's truly getting the PROPER air/fuel mixture and its getting GOOD spark at the right time, only thing left is compression. Run a compression test to verify that the piston, rings, valves, etc., are all in working order.

There is nothing to time from an ignition standpoint, the only timing is that of the cam/crankshaft via the cam chain. If these are out of time a compression check should also tell you.

If the bike has been sitting a long time, the jets and passages in the carb are likely plugged with varnish from evaporating gas. This will definitley prevent starting. Spray some starter fluid in the carb throat and see if the engine fires. If so, it's a carb issue.

Also, how old is the gas in the tank? I left some for about 3 months in my EX and had a hell of a time starting it till I filled the tank up with new gas. The volatile components in the gas start evaporating immediately, making nearly worthless by my 3 months.

BTW, if you're getting this for 'next to nothing', it's still worth it even with any serious issues. The parts, sold separately, are usually worth more then the whole.

Good Luck!

[hsbarker81]

thank you for your help

next to nothing is $800

the bike is a 99-01 (unsure)

the cheapest i have seen a 400ex go for here is 1800 and it was i rough, but running shape

does this sound reasonable for a clean bike?

[Nick1225]

my 2000 400ex doesnt run for more than ten seconds. I bouth the ex for 500 bucks. Don't know what is going on. Also when it does run, it is smoking. Don't know what to do. someone please help

[QuadManiac]

If it's on the west coast, I'll buy it! Seriously, if the bike is clean, no frame cracks, running gear all looks good, it's probably a good deal even if it does require some significant work to make it ride worthy... what amount of work are you willing to do?

Is it on the west coast (contiguous 48), lol?