Motor Life

I was just wondering what the life expectancy is on the 400ex motor. I was also wondering if there are any parts that should be replaced after a while(ie bearings, timing chain etc..). I know these motors are extremely durable and have a long life but i dont really know the details. Thanks.:D

c'mon people this is interesting and quite important if you plan to keep your motor in good shape after lots of hrs.

[oynot400]

Do your maintaince, change the oil, check the valve, stuff like that. The only Honda part on mine that failed was a rear axle bearing. If you keep take care of your quad it will take care of you. :D

[TrX465]

CHANGE YOUR OIL.....thats the biggest thing for our motors and dont use synthetic...i dont care what anyone says dont specialy if you change it often...but hey thats my opinoin and my motor is pullin great

thanks guys, anyone else that has a motor with a lot of hrs on it? Im glad to hear about the oil thing and how reliable and long-lasting these motors are. I use a natural 10w-40 honda oil. How long have you guys had your quads? As many replies as possible would be great.

[cbrown400ex]

TRX465 whay do you not like synthetics? I switched to mobil 1 red cap(15-50 which is by everything I've read and experienced wet clutch compatible) It solved all my loud valve train noise and doesn't breakdown prematurely like the honda gn-4 did. rida682005 read and ask around about mobil 1. I haven't heard anything bad about it. And most people will agree that a full syn. oil is better than a conventional oil for a high temp engine. Which the 400ex is a very high temp engine. Just my opinion though. CJ

[Wheelie]

I've used Honda GN-4 oil in my 400ex since it was new, no complaints here.:D Ridden hard for 30mos. and still going strong.

I'm going to take a comp. test of it here very soon, it doesn't seem to run as strong as it used too, then again, it's probably just me.

[400exRacerX]

I use GN-4 oil the hole time I've my quad too. Haven't had a problem yet! The only thing that has fialed on my motor so far was an intake valve seal.

[oynot400]

Originally posted by TrX465
dont use synthetic...i dont care what anyone says dont specialy if you change it often
I was told to use synthetic over a natural oil. I was told that a natural oil will not protect an aftermarket cam like a synthetic will. I was told this by my engine builder and my Honda dealer. :D

[TrX465]

hey you guys use what you want to use i just dont use sythetic
and im not trying to start anything...its just my preference

[cbrown400ex]

Wasn't trying to start anything. Just was curious why you didn't like synthetics. CJ

[TrX465]

and believe it or not my motor runs pretty decent as far as temps running alky really helps that

[cbrown400ex]

That's great, but what do you have against synthetic oils? Are you saying you do not need the added protection (b/c your running alcohol) or is there some other reason. From my experience and many others I have talked to, the full syn. oil is much better for the 400ex than the gn-4or any other convential oil. I am pretty sure gn-4 is made my kendal (may be some other company) for honda and it is their low grade oil. But your are right. To each their own. If you are satisfied with the results from the oil your running that's all that matters. CJ

[400exBro]

i run 15-50w Kendal full syenthic and it runs better than before, a lot cooler and the oil holds up longer as well but still i do my oil change every 6 months with my valves, i have been told that kendal oils are the best to run in small engines.
lata
Bro

[oynot400]

I wasn't tring to start anything either, I was told because of my cam to run synthetic. Something about it protects the cam better for aftermarket cam.
One of my friends had a warrior that he punched out and put in a cam. He ran natural oil, a month later the cam was junk. That was his experience, it just helped me to decide to run synthetic.