My at makes the same sound you are discribing. believe it or not is is the gas gauge chattering!

 

4455duck,

You silly man. The gas gauge does make a noise, when my AT is not running. But when I am on the throttle, a valve like sound comes from the engine. That Sir is the noise we are talking about.
The noise is the main reason I bought the extended warranty. I didn't want to waste my money on it but with a first year unit who knows what will happen.

 

We use a stethoscope to locate the noise on my machine. The chattering noise at high rpms came from the gas gauge. My maching has done it since it was new. It sounds like it is comming from the bottom of the engine, but I now believe the needle vibrating in the gas gauge is the culprit. 1500 miles, doesn't burn oil,smoke, and it runs great.

 

I've been calling Honda Customer Support at 866-784-1870, selection 4 is for ATV's. I have had the valves adjusted and that did decrease the rattling noise but again, mine is sending out blue/white smoke and loosing oil so I am guessing that I burnt a valve seat or something in the piston rings. It probably is important for all AT owners with this problem to report it so Honda will have to deal with it.

 

One more answer, you asked about it possibly being clutch plates. I also had to have the ECM replaced on mine and when they did that they inspected the clutch plates and found nothing wrong. I will let you know what the next dealer says after I get it up there.

 

all hondas do this it is becouse there is a little slack on the piston rod its the way honda has designed it

 

the only way to get rid of it is to have your motor built by white borhters or someone like that and mine dosnt do it any more but again mine is not stock at all and the new rod they put in is custom its been weighed and cut to go with the stroke

 

Why there is a slack in the piston rod !???

 

its just the way all atvs are

 

So the chattering is from slack in the piston rods? My recon didn't make a noise like this at all. Why does it seem like that it's only the AT's that do it? Thanks for any replys