Yeah.. that Big Gunn Exhaust system he has just doesnt seem right.. The end of the tailpipe sticks out beyong the rear grab bar.. So if you stand it up to anywhere near vertical, its just gonna rip the muffler apart.. Which is EXACTLY what it did....
The oil filter was/is installed correctly. The bike was used when he bought it, it was purchased thru H&W Honda in Marshall..
Maybe he just expected too much out of it... He's coming from an old 220 Kawasaki Bayou 2x4 that ran flawlessly for over 10 years. That bike was ran hard, sunk, flipped, crashed, caught on fire, left sitting in a pasture for 2 months, fell out of the back of a moving vehicle, ran head on into a steel gate,.... etc.. ya'll get the idea... He fully expected it to hold up as well or better than the Polarises I ride... It hasn't...
Oh well.... we will fix it and see what happens..

 

haha, this is some funny sh*t.


'oo 400ex. RIDE HARD TILL THE F'IN RINGS BLOW OUT THE F'IN CAM!. F'in RINGS!!

 

He needs a Wolverine modified to 500cc and manual clutch if he wants a sport bike that will go muddin with the rest of them and still be reasonably agile and flat out move. A 400ex would still handle better and be faster but that’s the trade off for mud performance. I know the manual isn’t best for mud but it’s a trade off for when it’s not in mud. It would still have some of the fun of the 400ex mx type feel.

Only problem with the small bike in the mud is he’ll get covered with it from head to toe.

I go around mud holes if I can.

 

Is the machine possible overfilled with oil? When the oil level is too high, oil is pushed out of the vent at the rear of the case and into the air intake tract. What would this cause? Excessive smoking and power loss! Hope this helps!

 

Gary,
We have checked the oil in every concieveable different method suggested.... Late last night, we even drained the oil, changed the filter, and re-filled it... Still smoking..
Im going to make an adapter (out of an old sparkplug and an air hose fitting) sometime this week so I can run a compression check on it.
I have a compression guage that you just HOLD in place, but they aren't very accurate.. We DID try it, but it only read about 115 lbs. of compression... (I HOPE thats not right anyway)
It will get fixed though.... Just kinda disappointing..
BTW... We did find one problem that probably contributed to the engine failing...
The crappy Big Gunn Exhaust broke, and also started a small leak where it joins to the headpipe.. That leak burned a small hole into the lower corner of the airbox.... We did cross some 1-2 ft. deep water so it probably ingested some small amounts of water... Its running a K&N and outerwears... But undoubtedly that wasn't enough..

 

Service manual says the compression should be between 100 and 129 PSI, so you could be OK if you got an accurate reading.

 

Try running some 20w50 in it... The EX runs hot and will break down lesser oils very quickly if ridden hard. Mine would blow out a puff of smoke when letting out of the throttle after the break-in with 10w40 conventional oil. I then switched to 20w50 and the smoke disappeared. I now run Mobil 1 15w50 and have no trouble at all.

 

If your rings are good Check your crank it may be junk. When a bike smokes real good alot of the time the bottom bearing is bad and the pistion ****'s and the oil goes by the rings. I have seen the rods crack on the bottom side of the 400ex allready. Look good if you miss it, it is a $$$ mistake.

 

I agree with the heavier oil idea, I tried it and it works. Am I the only one who thinks that the clutches in a 400EX are worthless? I'd like to know your opinions?

 

I haven't had much trouble out of mine, but I have a friend with a '99 that's chutch will chatter when abused (but keep in mind that he probably weighs in at 215-220)