Loud clacking sound coming out of my engine when I'm idle.

[Monkeytofu]

Hey guys. I had some free time today so I decided to change my extremely old coolant and flush the whole system. After flushing out the system and replacing some parts I had painted, I took the bike for a test run and there was an extremely loud clacking sound coming from my engine.

I've had some clicking noises before and I suspected by cam chain, but this was way loud and the sound came from an area much closer to my carbs.

I increased the idle speed as it was pretty low sitting around 1K rpm but that seemed to make it louder (at least in my mind) and I haven't touched anything else today.

My friend who worked on my bike with me thought it might be the valves. Here's a video of the engine. Maybe you guys will know better than I do what it is:

Link to original page on YouTube.

[alex.s]

Link to original page on YouTube.

it sounds like your engine is literally about to explode. and i'm not at all kidding right now.

sounds like a piston hitting valves and head and all kinds of good ****... probably time for a new engine

[lgk]

did it sound like this before the coolant change?

[Monkeytofu]

Originally Posted by lgk

did it sound like this before the coolant change?

No, not that I recall. I've had the bike in the garage for maybe 5-7 days (occasional 30 minute trips to the store) and it wasn't this loud.

[DaBlue1]

When was the last time you changed the oil and did a valve adjustment?
How many miles on the bike?

[Monkeytofu]

Originally Posted by DaBlue1

When was the last time you changed the oil and did a valve adjustment?
How many miles on the bike?

I haven't done a valve adjustment, but the previous owner might have. He kept care of his bike from what I can tell. I may go through his mechanic receipts to see when/if he did it.

Last time I changed oil was maybe 1 month ago along with the filter. I have about 18K on my bike, about 4k of that is mine.

EDIT: Looks like the PO didn't do a valve adjustment. No idea why it would start needing adjustment after changing my coolant though. Maybe just coincidence if that's the issue.

[DaBlue1]

Was the engine cold or hot in the video? A cold engine can exhibit a little clacking, but yours seems a bit louder than normal.

[lgk]

pull the oil using a clean pan, see if there is any shavings...

[alex.s]

Originally Posted by DaBlue1

Was the engine cold or hot in the video? A cold engine can exhibit a little clacking, but yours seems a bit louder than normal.

you can hear it getting louder and worse as the engine heats up. op's right the valves wouldn't jump that far out of spec that fast unless something was wrong. like a blown journal bearing sending the piston into the valves and head. you can also hear a nice clunk at every other fire once it starts to run for a few seconds. cam chain doesn't do that. valves clearances don't do that. pistons do that though.

[Monkeytofu]

Originally Posted by DaBlue1

Was the engine cold or hot in the video? A cold engine can exhibit a little clacking, but yours seems a bit louder than normal.

Yeah, it was the same level of sound when it was cold or hot so it wasn't anything to do with engine temperature. Only ever noticed the sound when ever I was sitting idle at a stop light or stop sign though.

Originally Posted by lgk

pull the oil using a clean pan, see if there is any shavings...

What would that show me? I've never messed around with my engine before so no idea what you're looking for.

[lgk]

Originally Posted by Monkeytofu

What would that show me? I've never messed around with my engine before so no idea what you're looking for.

if there is metal particles in the pan then most likely your bearings are gone.

[Monkeytofu]

Originally Posted by alex.s

you can hear it getting louder and worse as the engine heats up. op's right the valves wouldn't jump that far out of spec that fast unless something was wrong. like a blown journal bearing sending the piston into the valves and head. you can also hear a nice clunk at every other fire once it starts to run for a few seconds. cam chain doesn't do that. valves clearances don't do that. pistons do that though.

Is there anything I can check for that would tell me it's the pistons exactly? Any parts of the engine shaking, shavings in the oil as lgk suggested, etc.

I've been slowly learning about engines and bikes as I've gone through and repaired/replaced parts on this bike. I have no idea how to diagnose or repair the pistons or if that's even something that's possible.

[alex.s]

check the oil

[DaBlue1]

At this point I would recommend you take it to the shop and have it repaired correctly. I'm betting that you need a valve and cam chain adjustment. BTW, what weight oil are you using in that hot as hell Texas Heat?

[lgk]

checking the oil, is the cheapest thing to do at this point...

if the valve adjustment was never done, then top end is pretty much worn.

[DaBlue1]

Originally Posted by lgk

...checking the oil, is the cheapest thing to do at this point...

+1

[alex.s]

he probably also needed a valve adjustment before things went down hill... the cam chain is probably out of spec from it. checking the oil is free. you can also look at the spark plugs. they will tell you a lot about whats happening in the engine.

[Monkeytofu]

Originally Posted by DaBlue1

At this point I would recommend you take it to the shop and have it repaired correctly. I'm betting that you need a valve and cam chain adjustment. BTW, what weight oil are you using in that hot as hell Texas Heat?

I'm actually not sure

My mechanic only has it listed as "repsol" on my receipts and I never asked him what he used exactly. I'll be doing it myself the next time it needs to be changed, which might be tomorrow if draining the oil is the best advice right now.

[Monkeytofu]

Assuming there's no metal in the oil when I take it out (in case I don't have access to the forums tomorrow) what else do you think it could be?

Also should I just use a synthetic 10W-40? I haven't had any issues with the the oil my mechanic put in during the spring even when I took ride in 100 degree weather. I mostly ride during the night, so high heat isn't usually an issue for me.

[lgk]

either way it would be a bad idea to ride it until you figure it whats wrong.

[alex.s]

however if you do decide to risk it, please record it. bikes exploding make the best youtube videos.

[lgk]

Originally Posted by alex.s

however if you do decide to risk it, please record it. bikes exploding make the best youtube videos.

wear a cup though...

my girlfriend said i had balls of steel, but it still stings after being hit with shrapnel...

[davenay67]

Check your valve clearances too. To be honest, valves that are too loose will make this exact same noise. You *might* have nothing worse than valves that need a good adjustment.

Relatively quick and easy to check clearances.

[the big mike]

Let it be, it sounds almost like a Ducati

[Monkeytofu]

No metal shavings in the oil. About to adjust the valves. My cam chain looks perfectly fine as well.

There should be no play in the cam chain right? While I'm in there, is there anything else I can check/adjust?

[davenay67]

Originally Posted by Monkeytofu

No metal shavings in the oil.

Did you pull the oil screen, or just drain/inspect the oil..?? Any shavings/debris will be trapped in the oil screen.

[alex.s]

measure the cam chain and see if its out of spec

[Monkeytofu]

Originally Posted by alex.s

measure the cam chain and see if its out of spec

How would I go about doing that? Three of the valves were waaaay too tight, and we're in the process of fixing those. Two down 4 to go.

[alex.s]

uh maybe @Motofool remembers the service spec. you measure the distance between 20 axles in the chain. its something like 125mm-127mm. over it and the chain is done.


dont forget if you dont retract the CCT when you put it back in, you'll put unwanted force on the cam chain and stretch it out. edit: no idea what kind of cct is in the pregen so this may not be needed??

its a good idea to check the oil screen when you change the oil. larger pieces wont make it through and the only flakes you will see will look like glitter. if the oil is old enough you wont even see it if you dont run it down a slope and thin it out

[Monkeytofu]

Originally Posted by alex.s

uh maybe @Motofool remembers the service spec. you measure the distance between 20 axles in the chain. its something like 125mm-127mm. over it and the chain is done.


dont forget if you dont retract the CCT when you put it back in, you'll put unwanted force on the cam chain and stretch it out. edit: no idea what kind of cct is in the pregen so this may not be needed??

I haven't taken it out of the actual engine, Going to adjust the valves while I have the cover off. I'm just going off what I can see from the top where the chain is going over two gears.

I'm thinking the only issue right now is for some reason or another these valves just reached a point where they became waaaay too tight. Might be just a coincidence with the coolant change, but we'll find out if this fixed it once we can get the bike started safely again.

[alex.s]

maybe you didnt bleed the coolant properly and it overheated a bit and threw the valve clearance out of spec. i would make sure and look behind the oil screen just in case. measuring from on top of the cam gears should be ok. you would probably want to make a few measurements in different parts of the chain to make sure its not uneven.

[Monkeytofu]

Took the screen off, there were two very very small shavings after I cleaned the dirt away. We also found a couple of rocks on the screen but they don't seem to be metal

Thoughts? The little ridge above some of the cam lobes are very slightly worn if you look at them closely.

[alex.s]

interesting... take photos of the shavings? what do you mean rocks? i would put a catch pan under it and run a bit of oil through it with everything open and see what flows out

[Monkeytofu]

Originally Posted by alex.s

interesting... take photos of the shavings? what do you mean rocks? i would put a catch pan under it and run a bit of oil through it with everything open and see what flows out

We accidentally dropped a socket in the engine, and now we're trying to get that. Idiot mistake I know :x

it was a small, brown and gray rock. I'll get a picture of the rock and the shavings to you guys in a few.

[Monkeytofu]

Sorry for the blurry pic, phone can't focus that well. You can see the shiny metal specs in the black filter though.

[alex.s]

what color are they

do they look tanish orange like brass?

[Monkeytofu]

Originally Posted by alex.s

what color are they

do they look tanish orange like brass?

One of them may be or it could just be covered in oil. but the other 2 flecks are shiny silver.

[alex.s]

maybe its nothing

[alex.s]

this is what bearing debris looks like:

[Monkeytofu]

Yeah, it's nothing even close to that. I think the rock was from the ground and made it on to the screen. I don't think the previous owner had cleaned it. Socket pulled out and we're back to business.