I could use your help with this one. I just got back from Montana with my new 500 EFI. When driving up hill (w/passenger on the back) under load I'd hear ticking sounds. It didn't sound like knocking but more of a higher pitched "snap" or "tick". The rhythm of the ticking didn't coincide with the cycling of the engine. So to me it didn't seem like it was coming from the engine. FYI, it was operating at 6500 - 7000 feet on 87 octane fuel.

I'm new to atv's so maybe a knocking on an atv sounds like ticking?

Could it be?:

- EFI
- Exhaust system
- Pre-detonation (dieseling)
- Running lean

I've read a couple various posts suggesting a few things but nothing explicit. What is it? Any help or suggestions would be greatly appreciated!

 

Does its frequency relate to ground speed? You said it didn't relate to engine speed, but that doesn't tell us if it's related to ground speed. It might be in the axle or wheel, for example.

On my wife's 2006 SP500 EFI (the same quad as yours), she had a similar "ticking" sound that was speed related. Turned out that one of the plastic A-arm/axle protectors had gotten bent and was rubbing against a tire balancing weight. Warming it up with a heat gun and straightening it solved the problem at no cost.

 

It only occured when the engine was under load. Like pulling the machine up the mountain. When accelerating on flat ground, I noticed it occasionally while picking up speed... But it would go away once I leveled it off...

 

Injector noise, perhaps. Some injectors get louder when the interval increases (i.e. when fuel demands go up). That's not usually a good thing, and can be an indication of impending problems. I'd have it checked out if you can't find any simpler explanation for it.

 

Why do the mysterious things always happen to my vehicles? I always ask a question like this hoping for a simple/cheap/effective answer and I always hear "crickets"....

Well, its in the shop right now for its initial oil change and check-up. I also asked them to look into the ticking. I'm pretty cynical and jaded when it comes to dealerships, car dealerships. So I'm praying my experience with this atv dealership can begin on a positive note.

They'll have a tough time recreating the conditions under which the problem occurs. (Going up a mountain, in AWD, with a person on the back.) Particularly since there isn't even a molehill within 10 miles of the dealership. But they said "They have ways...." I said "I don't want to know!"

 

If they have a dynometer, they can simulate any engine load condition. Or they could rig up some sort of simple mechanical load, such as an improvised sled pull across their parking lot.

 

how many hours dou have on this machine? If it has never had the valves adjusted, check those first.

 

Well, the dealership didn't find anything. Of course, they'd have to actually want too.

I'm starting to wonder if its a cv joint or u-joint? My truck made a similar sound ticking sound under load and it ended up being the u-joint in the driveline.

 

as I have said before I am no engine guy but try this:

Get it warmed up and throttle the crap out of it with the braked fully engaged (becareful) [img]i/expressions/face-icon-small-smile.gif[/img] If it's engine related it will tick. If it doesnt - thats a good thing, look for something else.

I have a prob with my 06 Dodge Ram that ticks under load exactly like you are describing and the dealer told me it was the transmission and it was normal. Of course didnt belive him so I did what I just described (to put the engine under load) whithout moving the wheels and it didnt tick at all.

just my 2 cents [img]i/expressions/face-icon-small-smile.gif[/img]