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Engine knock guidance

Devil920

Guest
Guest
Hey guys, I've owned my 98 Connie for about 6 months now and loved it. Put a few thousand miles on it and no serious problems up until this point. I was out riding with my buddy and noticed a light engine knock / tap, we got the bike the 4 miles home and drained the oil, sure enough there's some metal bits in it. Put new oil in and it seems to have gotten louder. There's not much metal in the oil but there's a few specs. First test was a bent connecting rod and as far as I can tell there isn't one. I did notice that spark plug on cylinder 4 was coated in oil and the plug connector even had some on it. I've never done engine work before so I'm looking for some guidance on what to look into / test and learn how to do. Thanks!

*Edit* Forgot to mention the knock sounds like it is from cylinder 3 or 4
 
The oil on the plug/boot is from a well gasket that has failed. That's minor and unrelated to the metal bits - which may not be as bad as it sounds. The starter/alternator chain and the slack device could fail and allow for some metal to metal contact - same with the cam chain if that adjuster failed. I'm sure someone more knowledgeable than me will respond.
These engines are very durable - hopefully it's an easy fix. When I have internal engine concerns I occasionally send a used oil sample in for analysis - Blackstone is fast and reasonably priced. A sample now won't be helpful, but in the future it's a good way to see what the engine's condition is.
 
Hey guys, I've owned my 98 Connie for about 6 months now and loved it. Put a few thousand miles on it and no serious problems up until this point. I was out riding with my buddy and noticed a light engine knock / tap, we got the bike the 4 miles home and drained the oil, sure enough there's some metal bits in it. Put new oil in and it seems to have gotten louder. There's not much metal in the oil but there's a few specs. First test was a bent connecting rod and as far as I can tell there isn't one. I did notice that spark plug on cylinder 4 was coated in oil and the plug connector even had some on it. I've never done engine work before so I'm looking for some guidance on what to look into / test and learn how to do. Thanks!

*Edit* Forgot to mention the knock sounds like it is from cylinder 3 or 4
When my alternator chain tensioner failed the sound resembled a knock . Try the screwdriver stethescope around the clutch cover and elsewhere to pinpoint the sound . When that tensioner fails it can slap the clutch basket and chew it up which may account for the metal you're seeing . It's easy to pull the clutch cover and have a look and not too tough to repair . Do it on the sidestand and youll only lose a little oil .
 
Thanks for the recommendations! I'll update on thursday as I had to leave the bike at my buddies and get a ride home to make it to work.
 
I have a replacement motor...actually, a whole bike...SISF's Seventh Gear, Torque Cams, Carbs with Over Flow Tubes, SPOOFAK, T-Cro's shifter and stick coils, 17" wheels with Radial Mount Front Calipers and Oversize Brake Rotors, ZZR 1200 Rear Shock...etc. PM me if you are interested...

Little Rock...
 
I'm rewriting my last two posts on the thread just to clarify some conflicting information. Knock is coming from the bottom right side after further examination, no metal in oil filter
 
Check for hydrolock (measure cylinder pairs).

A bent rod can be severe enough to cause a knock in that area.
 
Lower right side is where the alternator tensioner lives . Id pull the clutch cover and take a look . If its been slapping the clutch basket you will see the marks where it hits .
 
I did pull the cover, it was holding the chain tight as far as I could see, obviously not under the load of a spinning engine though, there were a few marks on the clutch basket although didn't know if they were related. I'm going back Wednesday and ill upload some photos to show the marks and get advice on if you guys think it's related. Thanks again for all the help so far!
 
You found your issue . Change that tensioner and measure the chain for stretch . Mine was a full 1/8 inch out of spec . I believe I spent about 225 in parts . you can see the end of that tensioner is beat up . Definitely do not ride it until you fix that . It's a grenade waiting to blow .
 
You could take a chance with this . The chain and tensioner is all you need but looks like a good deal . All years should be the same .
Thanks for the great find! Saved me $100 so I pulled the trigger on it and it should arrive on the 9-10th and I'll be able to put it in within a week of that and give an update. Thanks again for all the help!
 
Awesome . Hope ya get back on the road soon . I heard this is a rare occurrence on the concours but there have been several instances lately . More common on the ZRX engines which is basically the same tensioner design .
 
Update, noise is quieter so that was one of the issues, the noise is still there though unfortunately. Sounds like it's probably coming from where the connecting rods attach to the crankshaft. I noticed exhaust on the right side is warmer than on the left if that means anything to anyone. I've attached an audio clip that sounds pretty close to what I'm actually hearing if that helps anyone. Thanks again for all the help so far and any insight someone can offer moving forward.
 
Update, noise is quieter so that was one of the issues, the noise is still there though unfortunately. Sounds like it's probably coming from where the connecting rods attach to the crankshaft. I noticed exhaust on the right side is warmer than on the left if that means anything to anyone. I've attached an audio clip that sounds pretty close to what I'm actually hearing if that helps anyone. Thanks again for all the help so far and any insight someone can offer moving forward.

Where are you located ( since the new forum does not even show a region !šŸ˜ž) ? Maybe a member could drop by and take a listen ?
 
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