my 400ex is the most unreliable thing that ever came from honda. it died out on hte trails, i wasnt beening hard on it. when i turn it over it sounds like it doesnt have compression but when its in gear it wont roll so i have no idea whats wrong with it. someone plz help.

 

Holy Cow!!

Really? Did you buy it new or used? Do you know how to check for spark and fuel?

 

I always thought the stock 400ex was one of the most reliable sport quads out there. [img]i/expressions/face-icon-small-confused.gif[/img]

 

it has gas andi tried to check thespark but i dont have the socket to take theplug out. so i have to buy a newsocket and i will have it in a couple of hours soill reply then.

bought it used btw

 

Well, buying it used, you may have bought the last persons problem.

Get the plug changed, and don't just check the air filter, check the boots too. Look at the carb. If the intake looks dirty, it's gonna need a good cleaning or maybe even a rebuild.

Good news on these is, once you get it running, it should stay that way for a long time.

 

<div class="FTQUOTE"><begin quote>Originally posted by: kempre

my 400ex is the most unreliable thing that ever came from honda. it died out on hte trails, i wasnt beening hard on it. when i turn it over it sounds like it doesnt have compression but when its in gear it wont roll so i have no idea whats wrong with it. someone plz help.</end quote></div>




I have to respectfully disagree. I purchased (new) the biggest POS ever manufactured by honda. I bought a new motorcycle some years ago (OK, so it was in 1986) that required a new engine every 5,000 miles. 15,000 and three engines later I got ride of the POS.

 

It has a spark. i think that one of the exauhst valves are stuck open. anyone know if its going to take breaking the crankcase open to clean to valves off?

 

<div class="FTQUOTE"><begin quote>Originally posted by: DeeDawg

<div class="FTQUOTE"><begin quote>Originally posted by: kempre



my 400ex is the most unreliable thing that ever came from honda. it died out on hte trails, i wasnt beening hard on it. when i turn it over it sounds like it doesnt have compression but when its in gear it wont roll so i have no idea whats wrong with it. someone plz help.</end quote></div>









I have to respectfully disagree. I purchased (new) the biggest POS ever manufactured by honda. I bought a new motorcycle some years ago (OK, so it was in 1986) that required a new engine every 5,000 miles. 15,000 and three engines later I got ride of the POS.</end quote></div>

ok so maybe not the worst but it still sucks. i boughgt it and the clutch plates went out and theni get ti back from the shop and the bearigngs are worn to hell and the rear axle had to be replace along with the barring carrier.

 

You don't have to break the crankcase open to get to the valves. If you put the piston at TDC on the compression stroke, you can remove the valve cover and rocker assembly. I don't know how much you payed for it, but it sounds like having the work done at a shop could eat your wallet alive. If I was you, I would pick up a clymer (or similar) service manual and run through the test procedures. I don't know how mechanically inclined you are, but if you get a service manual you can look it over and see if you think you can handle it.

 

It definitely sounds like it wasn't cared for very well.

In that case, there are a multitude of things that can (and probably will) go wrong with it when you get it running again.