Metal Tapping Sound from Engine

[Tiger12XC]

Shouldn't that be covered under warranty bad bearings or wrist pin?

[jbfla]

Originally Posted by CSaddict

Sent the video to friend that ran the service department at the local Yamaha/Suzuki/Can Am dealer and he said it sounds like a wrist pin or crank bearing issue.

Edit. listened again and now thinks rod bearing.

Thanks, CS, I appreciate the effort.

The first thing I thought of when I heard the sound was a "rod knock".

I know what is involved in fixing that.

And that's the last thing I wanted to deal with.

Currently looking for a local shop to get another opinion.

jb

[jbfla]

Originally Posted by Tiger12XC

Shouldn't that be covered under warranty bad bearings or wrist pin?

Yes, it certainly should.

The problem is getting it repaired. There are only two local independent motorcycle shops in town (no major brand dealers). Both are run by "kids", IMO.

The alternative is to ship it back to CSC for repair...

jb

[jbfla]

Thanks to all that offered suggestions as to the cause of the metal tapping noise.

Here is another video of the sound:

http://vid42.photobucket.com/albums/...pszldnffs4.mp4

There has been no definitive diagnosis as of now, except that it is an internal engine problem, and that the sound is not at the same speed as engine rpm.

Here are my options:

...Disassemble the engine myself, find and repair the problem, with CSC's telephone/email assistance.

...Remove the engine myself, crate it, find a shipper, and send the engine to CSC. Then reinstall the engine when it is returned.

...Find a local shop to diagnose and repair the problem.

...Ship the whole bike back to CSC to have them diagnose and repair the problem.


In communication with CSC there was no mention of the option published in Joe Berk's blog and book,

"We'll find an independent shop in your area and arrange whatever maintenance your bike needs directly with them."


If someone had ever heard this exact sound before, and it were simply a matter of removing the engine side cover for a repair, I would attempt it.

However, to blindly take apart the engine without knowing what to look for, is something I am not comfortable doing.

I have made a decision as to what I am going to do.

I am curious to know how many RX3 owners are willing to take the engine apart themselves, and attempt a repair?
.....not counting SpudRider..

jb

[Lee R]

I'd probably check the price for shipping and if it's prohibitively expensive I'd take mine apart with assistance by phone as needed. There's so much content here, on youtube and from CSC that it shouldn't be that bad to do.

Most Singles are pretty easy to take apart and if your meticulous you'll probably do a better job than a shop who's trying to get it done as fast as possible.

Rocky Mountain ATV has some excellent video's that show what's involved with a tear down of a Single.

[kumatae]

that's a total bummer... if you got the time and can afford to have the bike sit around for the time being, i'd attempt it myself but i'm not in that situation as bike makes all the difference in my commute (splitting lanes). might want to look in to shipping the engine but then again, taking the engine out is going to take some time as well. you've got a tough decision...

oh and btw, i'm on my 3rd valve clearance check in last 7 days as well!

[SpudRider]

Originally Posted by jbfla

...I am curious to know how many RX3 owners are willing to take the engine apart themselves, and attempt a repair?
.....not counting SpudRider..

jb

Okay, leave me out of the discussion.



I'm wondering if the noise might be caused by damaged bearings on the hub of the clutch basket, as described by Riceburner, in the following thread.

http://www.chinariders.net/showthread.php?t=16000



Apparently, this problem can be caused by not applying enough torque and/or not bending the lock washer on the nut which secures the clutch basket to the main shaft.

Is is possible the sound is coming from the clutch cover on the right, bottom side of the engine?

[SpudRider]

Originally Posted by jbfla

...Here are my options:

...Disassemble the engine myself, find and repair the problem, with CSC's telephone/email assistance.

...Remove the engine myself, crate it, find a shipper, and send the engine to CSC. Then reinstall the engine when it is returned.

...Find a local shop to diagnose and repair the problem.

...Ship the whole bike back to CSC to have them diagnose and repair the problem.


In communication with CSC there was no mention of the option published in Joe Berk's blog and book,

"We'll find an independent shop in your area and arrange whatever maintenance your bike needs directly with them."


If someone had ever heard this exact sound before, and it were simply a matter of removing the engine side cover for a repair, I would attempt it.
...

If the problem is caused by bad clutch bearings, the repair only requires removing the clutch cover, and the clutch basket. The process is described in the Clutch Assembly tutorial, located at the following link.

http://www.chinariders.net/showthread.php?t=15612



However, you are certainly justified to "find a local shop to diagnose and repair the problem."

[jbfla]

Originally Posted by SpudRider

Okay, leave me out of the discussion.

Spud, there is no leaving you out.

As chief cheerleader for CSC/Zongshen, second only to Joe Berk, your posts, like it or not, are probably responsible for many sales of RX3s.

I know they greatly influenced my purchase.

Originally Posted by SpudRider

I'm wondering if the noise might be caused by damaged bearings on the hub of the clutch basket, as described by Riceburner, in the following thread....

Is is possible the sound is coming from the clutch cover on the right, bottom side of the engine?

I have re-read Riceburner's thread about the clutch bearings.

I'm not averse to removing the clutch cover and taking a look.....I'm due for another oil change.....

If it is the clutch bearings, wouldn't the sound change when the clutch lever is pulled in, or when the clutch is engaged when in gear?

It doesn't change in frequency or pitch when going through the gears.

Originally Posted by SpudRider

However, you are certainly justified to "find a local shop to diagnose and repair the problem."

I have taken the RX3 to the only two independent motorcycle shops in town.

Neither shop will even consider working on a Chinese bike.

At the first shop I did get 3 guys to listen to the engine, after offering to buy them lunch....

All 3 agreed that the sound was from inside the engine, but could not agree as to what was making the sound.

At the second shop, 2 guys listened to the engine running...without having to resort to bribery...

Again, they did not know what the sound was, but agreed it was coming from inside the engine.


Back at home, I used the stethoscope once more to listen to where the sound was the loudest.

It still sounded like it was in the valve train/cylinder area, but I know that can be deceptive.

In Riceburner's posts, the first 2 mechanics that listened to his engine thought it was a piston/rod/bearing knock.

jb

[CSaddict]

What about a broken chain guide?

[katflap]

Just a guess, I wonder if it is a problem with the cam auto decompression mechanism.

Broken spring or perhaps an issue with the supporting washer.

see here

http://www.chinariders.net/showpost....08&postcount=4

[maxhdrm]

Hey, it is not only Spud but all you guys that are willing and eager to share your knowledge that influenced my decision to purchase a RX3. Keep the knowledge coming!

[Eco Mouse]

It's almost always a muffler bearing that goes bad. In some rare and unusual cases, it's the Johnson Rod or Kuhneutson Valve. But judging by the sound, I'd say your due for new Piston Return Spring.

Which reminds, me... I need to check my blinker fluid. It's overdue for a flush, and I probably need to get a Round Tuit.

[SpudRider]

Originally Posted by jbfla

...If it is the clutch bearings, wouldn't the sound change when the clutch lever is pulled in, or when the clutch is engaged when in gear?

It doesn't change in frequency or pitch when going through the gears....

The sound would not necessarily change that much.

I mentioned the clutch bearings as the potential problem, because others have had this problem, and checking for this problem requires the least amount of work. I doubt you would even need to replace the gasket for the clutch cover. However, you would need a clutch holder and a torque wrench.

Since the local shops won't touch your bike, I think you are also justified to ask CSC to find a 'local' shop which is willing to work on your RX3.

If I were not on the other side of the country, I would certainly come by and help you, JB. I don't know for certain what is causing the noise. However, I'm sure a partial disassembly of the engine will reveal the problem.

[SpudRider]

Originally Posted by katflap

Just a guess, I wonder if it is a problem with the cam auto decompression mechanism.

Broken spring or perhaps an issue with the supporting washer.

see here

http://www.chinariders.net/showpost....08&postcount=4

Once again, it doesn't cost any money to remove the rocker cover, and inspect the rockers, cam shaft, tappets, et cetera. The rocker cover does not have a gasket. Instead of replacing a gasket, you merely spread a little black RTV between the mating surfaces of the cylinder head and rocker cover.