I have a '92 Fourtrax that I puchased used about six years ago and need advice on what to look for that indicates it's time to rebuild the engine. It's always seemed to have a slight knock whenever the engine is under load (such as going up hills or in deep sand), however it doesn't burn a drop of oil. I know it's been a while since I adjusted the valves, however the knock doesn't sound anything like the ticking sound of loose valves. I've been thinking it might be rod knock but not certain. It doesn't get driven very hard or often since I use mostly during deer season in the Fall.

All comments and suggestions are appreciated?

Dan

 

I have the same knock on my 400EX. It was much more pronounced until I started running 91 octane. I was told here on this site that it is normal.

 

Thanks for the reply.

I checked with a friend who rides dirt bikes professionally and he said the same thing about Hondas being a little noisy once they get some hours on them. I'll also start using higher octane gas and adjust the valves and see what happens.

Thanks again.

 

Yeah, Rincons can make a klack kind of noise which seems to be normal, too.

If yours makes noise only when you are on the throttle hard, especially at lower RPM, that would be the classic description of pre-ignition/detonation, IE needs higher octane fuel...

You said that it's had the slight knock for the 6 years that you've had it... If it were a rod, I'd expect it would have gotten worse (or more likely blown up by now).

 

my 2004 and my 2005 rancher make a decent clinky noise at idle, so i think the notion that the honda's get a little noisy when they have some hours on them is pretty accurate.