cbr 929 clank noise.

fireblade929

fireblade929

Well-known member
hey guys, so ive been hearing this clanking noise on my bike for a while. i only hear it when the bike is on idle. it sounds like something is hitting the engine block. its very sporadic but the last couple of weeks ive been hearing it more constantly, even 2 or 3 times one after another like clank, clank sometimes it goes clank, clank.......clank.
could it be the cct? the bike has 33k and its been meticulously maintained but i cant pinpoint what that noise is.
im gatherin all the tools and parts i need to do a valve check (damn shop wants 1300 to do it) im also going to replace the cct with an aftermarket one hopping that will take care of that damn clanking noise.
the bike does not loose power, everything seems normal except for that clanking noise.
im very worried about that noise.
any help will be appreciated, thanks.
 
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mototireguy

mototireguy

Moto Tire Veteran
Manual CCT is a good non major surgery place to start.

Valve check, fresh air filter, etc good to do mileage wise and for peace of mind but unlikely the source of the clanky clank sounds.
 
fireblade929

fireblade929

Well-known member
i also red somewhere that it could be a bad fuel pressure regulator so im gonna replace that as well.
so if the cct is no longer good and the chain is kinda loose, could it be that the chain is hitting the engine block cuz is loose ergo making that clanking noise? but if the chain is loose doesnt that mean that the valves are out of sync making the bike loose power?
i have absolutely no power issues.
 
Hooli

Hooli

Big Ugly
Cam chains have internal slipper guides. There's no way it could be contacting the block.
 
ST Guy

ST Guy

Well-known member
fireblade929 said:
i also red somewhere that it could be a bad fuel pressure regulator so im gonna replace that as well.
so if the cct is no longer good and the chain is kinda loose, could it be that the chain is hitting the engine block cuz is loose ergo making that clanking noise? but if the chain is loose doesnt that mean that the valves are out of sync making the bike loose power?
i have absolutely no power issues.
Click to expand...

You wouldn't likely notice the difference in power. The "butt dyno" is notoriously inaccurate. Especially if things change gradually.
 
Busy Little Shop

Busy Little Shop

Man behaving bikely...
To troubleshoot an internal noise the first step is to establish the
rate at which it occurs... is the noise in time with the camshaft or
crankshaft??? camshafts rotate 1/2 the speed of the crankshaft...
possible source of camshaft speed noises are shim and bucket
clearances... loose cam bearing blocks... broken valve springs...
possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings...

Another source is normal clutch knock at idle... you see over time
slop develops allowing the gear teeth to knock about and thus the
noise... grab the clutch lever and the inner basket helps align the
outer basket and see if the noise deadens... the only cure to eliminate
the slop with new clutch parts...


To pin point the exact location of the noise hold a long tip screw driver or a
length of garden hose up to your ear and probe the suspected area...

attachment.php
 
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fireblade929

fireblade929

Well-known member
Busy Little Shop said:
To troubleshoot an internal noise the first step is to establish the
rate at which it occurs... is the noise in time with the camshaft or
crankshaft??? camshafts rotate 1/2 the speed of the crankshaft...
possible source of camshaft speed noises are shim and bucket
clearances... loose cam bearing blocks... broken valve springs...
possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings...

Another source is normal clutch knock at idle... you see over time
slop develops allowing the gear teeth to knock about and thus the
noise... grab the clutch lever and the inner basket helps align the
outer basket and see if the noise deadens... the only cure to eliminate
the slop with new clutch parts...


To pin point the exact location of the noise hold a long tip screw driver or a
length of garden hose up to your ear and probe the suspected area...

attachment.php
Click to expand...

the noise is very random. im gonna get an Stethoscope to try to pinpoint the noise.
"loose cam bearing blocks... broken valve springs...
possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings.."
wouldnt the bike loose power if all or some of this was the problem?
tnx
 
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mototireguy

mototireguy

Moto Tire Veteran
fireblade929 said:
"loose cam bearing blocks... broken valve springs...possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings.."wouldnt the bike loose power if all or some of this was the problem?
tnx
Click to expand...

Overthinking it and begging for near useless guesses.

Do the CCT, valve check, oil change (look for any odd metal flakes on drain plug magnet) and report back.
 
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afm199

afm199

Well-known member
Lots of info here, all good.

Start with the simple things. Noises like that are usually associated with bad CCT's, particularly on the Honda's.
 
msethhunter

msethhunter

Well-known member
It's a CCT. Honda is notorious for it, and is usually described exactly how you are describing it. If you haven't done one, make sure you either get help first, or know what you're doing first. If the chain slips, you will have to do a lot more than just replacing a CCT.
 
fireblade929

fireblade929

Well-known member
msethhunter said:
It's a CCT. Honda is notorious for it, and is usually described exactly how you are describing it. If you haven't done one, make sure you either get help first, or know what you're doing first. If the chain slips, you will have to do a lot more than just replacing a CCT.
Click to expand...

thanks but i dont think its cct cuz ive been doing some research about it and it sounds more like a rattling rather than a knocking sound.
but im going to replace that too.
 
fireblade929

fireblade929

Well-known member
a little update:
i did and oil change, didnt find any bits of metal in it (thats good right?) and the knocking sound has been less constant.
ive had 2 929's for the last 10 years and i thought i knew my bike from tail to headlight but this is driving me nuts.
next step is valve check and cct.
i'll keep you guys posted, thank you do much for the replies.
 
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