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Main Area => General GS500 Discussion => Topic started by: Rollin668 on November 04, 2003, 06:32:07 PM

Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Rollin668 on November 04, 2003, 06:32:07 PM
Sorry for all the caps - I'm a "tad" frustrated.

I recently got the bike running after replacing the ignition rotor but this morning on the way too work I noticed an unusual sound coming form the engine.  I clanking coming from the engine.  Couldn't quite place it.  It was raining this morning so I attributed it to that and figured I'd let it sit, cool down, and see how it goes on the way home.

Started off towards home (I work about 30 miles away from my work).  After so many miles the clanking got MUCH louder.  Almost violently loud.  And the shaking - GAWD - the shaking.  Anyway.  I pulled off the highway once I couldn't take it anymore and still was unable to figure out where the sound was coming from.  I also checked the oil and noticed it was a bit low so I put in more oil (nasty 10w40 Shell gas station oil!!!).  I swaid F-It and started on my way home.  The sound got louder and now it feels as if soming is loose in the engine.

I do feel a noticable loss in power (but it will still get up to crusing speed), the sound goes totally away when I pull in the clutch and let off the throttle, it's obvisouly engine related because as I accelerate it gets louder.  I'm pretty sure both cylinders are firing because without one cylinder I know there is a serious loss of power.  Anyway - I'm reserving the weekend to open the engine and start looking and poking around.  Anyone have any ideas?


Thanks.


UGH
Rolly
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Blueknyt on November 04, 2003, 06:46:38 PM
sounds like you have posibly spun a rod bearing. hard to say unless we hear it ourselves
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Rollin668 on November 04, 2003, 07:25:23 PM
So I'm gonna look into htis possibility, however, is the piece in question actually called the rod bearing?  I'm looking in the repair manual and the BikeBandit.com schematics, but no luck.  Can you steer me in the right direction?

And what do you mean by spun?  

thanks.


Rolly
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: KevinC on November 04, 2003, 07:36:06 PM
I'd actually bet on a counter balance shaft bearing. I have first hand experience with too many bottom end bearing failures at this point!

CB shaft bearing failure lets the engine run OK, but it makes horrible noises and vibrates like hell.

Spun means the bearing stuck to the shaft, and turned in the cases, or in the case of a rod bearing, it turns in the rod end.

Unfortunately, if it is a spun bottom end bearing, the cases will be toast, as well as the CB shaft. If it was a rod bearing, probably only the crank and the one rod would need replacing. Easier to find a used engine, and swap them.
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Yohan on November 04, 2003, 08:14:06 PM
Maybe you've got the wrong gas inside of the bike.
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Briliu on November 04, 2003, 08:16:06 PM
would too low an octane cause the nasty vibration? It will cause pinging, but thats not as loud as he is describing. I dont know if predetination will make the bike behave like he's describing either...

Heh, why am i posting when i dont know?! I guess to find out  :cheers:
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: KevinC on November 04, 2003, 08:20:07 PM
No.
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Blueknyt on November 04, 2003, 09:49:34 PM
low octane would just make it ping alot
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: yamahonkawazuki on November 04, 2003, 10:35:01 PM
get ready to spend some time&money on this one im afraid :cry:  :cry:
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Rollin668 on November 05, 2003, 11:49:34 AM
Okay so this weekend I will easily check the first obvious issue - the cam chain and tensioner.  If either is bad, it's a simple replacement.  

The 2nd thing is the counter balancer shaft?  How does one check this thing.  Will it be broken, will a piece be missing, or am I looking for slight variations in dimensions or size or something?  

Help!!!



Rolly
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: KevinC on November 05, 2003, 11:53:29 AM
When you pull the side covers off the engine you will be able to see the ends of the CB shaft. If it is a CB shaft bearing, you will have play in one end of the shaft - it will move up and down, and it ain't supposed to.

If you pull the oil pan off the bottom, and it has drifts of metallic "flour", then it will be a bearing. The finely ground metal is the remains of the bearing surface from one of the shell bearings.

It is pretty obvious when you split the cases. The bearing will look terrible, and likely the surface in the case where the bearing sits will be chewed up as well.
Title: LOUD CLANKING NOISE IN TH ENGINE!!!
Post by: Rashad on November 05, 2003, 04:46:41 PM
If its a rod bearing and you keep running it.. then youll konw, because the motor will lock up nice and tight, and one of your rods will turn black from the heat..(dont ask how i know) :x