Polaris ATV Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
Recently bought a sportsman 500 ho efi. has 145 hours,and there is some sort of rattling noise comining from the engine,seems to be on the right hand side,i can here it from cold start at idle and seems to get louder at higher revs espeacially riding if I hammer on it and a lot of people say that these bikes all have that noise and its normal howerever I really just want to know what it is! I changed all the fluids and spark plug. checked valve clearance and even took the bindex off and cranked with the pull rope to make sure it wasn't from the bindex.There is nothing that I can find that is loose. Any ideas?
 

·
Registered
Joined
·
7,442 Posts
Sounds like the clutching to me. Normal noise.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #4
The Bendix engages the flywheel. YouTube it. And someone else also told me it could be the clutch but I hear it more on the right side. Do you know anyway of trouble shooting to see if it is the clutch for sure?
 

·
Registered
Joined
·
7,442 Posts
Take the cover off. run the engine. If it's louder, you have your answer.

The bendix is part of the starter. as stated above, it's the part that engages the Flywheel to get the engine started. Once the starting sequence is disengaged, the bendix disengages the the flywheel and retracts back into the starter.
 

·
Registered
Joined
·
1,919 Posts
Ya may want to post up a brief video/audio of 'noise'. These are rather rattly engines to being with, there are many normal sounds! :cowboy:
 

·
Moderator
Joined
·
8,739 Posts
Yep, I know what a Bendix is. Polaris calls it a "starter gear". I've replaced dozens of them.
The OP referred to a "bindex" which kinda threw me.

Pictured below is the source of your rattling noise. I thought the OP was calling it a "bindex"...lol
In my experience, most all the Polaris machines with a recoil starter will have a little rattle on that side after they get a little age on them.

 

·
Registered
Joined
·
9 Posts
Discussion Starter #11
Yea I missed spelled it but like I said I removed the Bendix and ran it so I know the noise is not coming from that. My recoil starter did not have any play in so not sure I understand how it would be coming from there. It has the noise all the time even in neutral. It gets louder as rpm's increase no matter what gear hot or cold.
 

·
Moderator
Joined
·
8,739 Posts
When you had it off did you shake it? There is a whole collection of loose parts that make up the recoil mechanism. I don't think I've ever seen one that wouldn't rattle when shaken. Those big single cylinder engines vibrate a lot when running too.
That may not be what your particular noise is though. Could be clutches or something else. Might get a stethoscope and go over it to isolate the sound.
 

·
Registered
Joined
·
1,094 Posts
if the primary clutch spring is really weak it can cause a rattling noise.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #14
I did that with the stethoscope and it did not sound like it was coming from the clutch on the belt side. To me it sounded loudest up around top of the jug where the valves are. All the valves are within spec,should they make noise?
 

·
Registered
Joined
·
1,919 Posts
... All the valves are within spec,should they make noise?
Yes, as stated before, these are rattly overhead cam engines, there are lots of sounds to enjoy.

As requested before, I'd post an audio of your 'noise'. Are you sure the oil level is Full? That makes a big difference on my old 98's rattle level. :cowboy:
 

·
Registered
Joined
·
9 Posts
Discussion Starter #16
Yes it has plenty of oil and like I said I can't get it to upload for some reason. It up loaded to another forum with no problem but it won't do it with this one.
 

·
Moderator
Joined
·
8,739 Posts
hmm..how many miles/hours on that machine?
What kinda oil in it?
If its that noisy in the top you could have a cam or chain problem or an issue with the compression release mechanism or possibly the chain guide. I have seen all of the above at different times with those engines especially if they've been run with plain jane motor oil. You should use nothing in those engines but good synthetic. I prefer Mobile 1.
Might not be a bad idea to pull the valve cover and have a look see if it gets any worse.
You could drain the oil into a clean white container and open up the filter. Inspect both under bright light if you really think there's a problem. If something is coming apart it should show up in the oil.
 

·
Registered
Joined
·
1,059 Posts
the problem with your problem,you say it's rattling and the next would say it's normal.
how long we can't hear it there is no way to find out.
 
1 - 19 of 19 Posts
Top