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Discussion Starter #1
ADVICE...................SCRAP IT OR SORT IT........................................

I have developed a knock (pretty damn audible) that sounds to be coming from the valve train............having spoke to a few guys over the phone it has been suggested that my timing has jumped a tooth and possibly bent a valve or 2 which would be a very costly job

now I have a dilemma..............do I scrap it or do I sort it.........

THE HISTORY.....................

Fitted a manual tensioner a few weeks back, seemed to run fine, pulled like a train, last 2 days the engine has started to give out this highly audible tick, clatter, knock, seems to come from the valve train, gets hot quick, I swear I can smell fuel from the engine oil, no funny idle, idles fine, was getting vibrations, put screwdriver to my ear and went over the engine............definate knocking in the vale train/cylinder head, no loss of oil pressure, still starts and runs but was running funny, getting to high revs but loss of power I would say..............

what say you?
 

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Put the old CCT back in and see what happens, maybe the noise will go away.

Sometimes the chain will skip one, and the valves can open incorrectly causing pinking or detonation, but without hitting the pistons. You might be lucky enough that it just needs the timing reset. And a proper CCT.
 

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Discussion Starter #3
well I thought that it could be CCT needing adjusted, but I adjusted it ever so slightly and it is still knocking its head off, definite top end, would say over a few valves, bit hard to pin point with an aftermarket can, but it is highly audible, and definite knock, knock, knock................
 

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Might just be detonating.

IF you really had a valve knocking, I doubt the engine would run, it certainly wouldn't run on 4 cylinders.

STOP running the engine with the manual tensioner in it.
 

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ADVICE...................SCRAP IT OR SORT IT........................................

I have developed a knock (pretty damn audible) that sounds to be coming from the valve train............having spoke to a few guys over the phone it has been suggested that my timing has jumped a tooth and possibly bent a valve or 2 which would be a very costly job

now I have a dilemma..............do I scrap it or do I sort it.........

THE HISTORY.....................

Fitted a manual tensioner a few weeks back, seemed to run fine, pulled like a train, last 2 days the engine has started to give out this highly audible tick, clatter, knock, seems to come from the valve train, gets hot quick, I swear I can smell fuel from the engine oil, no funny idle, idles fine, was getting vibrations, put screwdriver to my ear and went over the engine............definate knocking in the vale train/cylinder head, no loss of oil pressure, still starts and runs but was running funny, getting to high revs but loss of power I would say..............

what say you?

At least do some diagnostics.
Check compression.
Are all four headers at similar temperatures?
Is there fuel in the crankcase?
Has the tensioner come loose?
 

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Discussion Starter #6
all four headers are cooking hot, small smell of fuel (I believe from the dipstick), oil looks kind of thin but is brand new, was burping cooling system this morning, some bubbles but not a lot, have a recording (audio), just back from a very knowledgeable and experienced bike tech (33 yrs all bikes, ducati certified), going in next week for diagnostics, will have to wait and see......

the tap seems to be on #3 cylinder valves, just hoping it's not big end bearing creating play and piston kissing the valve, but guy reckons it could be as simple as poor carbs/synch, I don't have any experience so it's a waiting game, fingers crossed it's not going to be bad............I love my blade, breaking my heart this...............
 

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What bike is it?
 

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Discussion Starter #13
this waiting is doing my head in, I've been hammering the sites and info, so I have a few questions...............

I've already sourced a engine, although it is in a bike and is gonna cost me in the region of 1500 to buy the bike but its only done 15k miles so I'm thinking buy that take what I need and punt the rest to cover some of the costs...... anyway the questions,

if my head gasket was knackered would it cause the noise I'm hearing, as if either water was getting into the oil thereby thinning it out, or if oil was getting past the gasket and somehow clogging the plugs and/or getting onto the valves?

I'm doing somersaults in my sleep and my butt is doing cartwheels trying to figure this out, I'm not good at waiting, esp when I have a small window of opportunity on what seems to be an ideal solution......................
 

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View attachment 58834 this is the audio...............sorry about the quality, I had the mic sitting at the cylinder head, above the headers

I can't hear anything that sounds like there's a dramatic problem.
If you block the muffler perhaps I might hear better, but I wouldn't be concerned.
 

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Discussion Starter #15
M8 I can't tell you the stress I'm encountering, i would get another recording but I'm laying off running her (damage limitation), i just have to make it to tues when the tech picks her up, have heard nothing but great things about this guy, real proper tech, pricey, but genius when it comes to bikes, a real old hand with loads of marques, really knows his tech.

I just have serious paranoia and nightmares over this, shes my everyday transport, work is a fair bit away, trying to strike a balance between cost and outcome.............more damage limitation lol...........examining all options with a very fine toothcomb.........i hate waiting lol
 

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Discussion Starter #16 (Edited)
View attachment rec_140305_170933.mp3

View attachment rec_140305_171630.mp3

ok guys heres another few recordings, rag over the muffler to drown out exhaust noise.....................

few things i have noticed, i took the radiator cap off to check for air bubbles, now i started her, took the cap off and let her get up to temp, now what happened was the coolant started to swirl, started to see bubbles appear, the coolant started overflowing the radiator neck (left a nice puddle on the floor) when i finished recording and turned her off the level in the radiator dropped right down, wayyyy down, so i topped her up and replaced the cap............................

a few other things,the clutch is noisey as hell, not much left in adjustment in the cable, also these wicked vibrations through the pegs and bars, but when i pull the clutch in they subside a lot................

other than that just the same old tap tap tap tap tap in the top end, tried listening in other locations but can hear the tapping no matter where i listen, do you think the CCT could need adjusting and this is causing the tap in the valves which is then transmitting through the casings and that's why i hear it everywhere?
 

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"if my head gasket was knackered would it cause the noise I'm hearing, as if either water was getting into the oil thereby thinning it out, or if oil was getting past the gasket and somehow clogging the plugs and/or getting onto the valves?"

Probably not the head gasket. That can sometimes sound a lot like and exhaust leak and you have poor performance all around. Also the coolant gets into the oil and makes it milky and foamy.
 

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Discussion Starter #18
i would say that her performance has dropped a little, she still revs high but there is a seeming lack of power, not as much oomph and she does seem to slow pretty rapid when i shut off the throttle........ah well will have to wait til wednesday and get the experts opinion, over 100 views and only a few replies....................communication breakdown!....lol
 

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All Honda CBR's have that rattle thru the bars, frame, and pegs until clutch lever is pulled. You can even hear it a bit. 100% normal.
You probably never noticed it before, but now you are looking for every little nuance and finally noticed it.
 
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