Hey guys! I'm new to this site so tell me if I do anything stupid. I've been searching this site for weeks now looking for help with my CBR.

For a couple of month ago I both my CBR1000f -87 with 40 000km. The bike had been standing in a garage for almost 5 years so it wasn't running smooth. After cleaning the carburetors the machine was up and running. But after a couple of weeks I recognized a slamering/ratteling noise from the engine. I asked the lokal workshop to confirmed that it sounded like the CCT. So I orded one and changed it. The problem was that the "old" cct wasn't looking old. It looked as good as the new one. But I proceed and put the new one in the machine. BUT, the ratteling sound was still there.
After searching this forum for advice I read about the Balance Shaft. So I tried rotate it anticlockwise to the end en then back to the first marker. There was a more whining sound but the ratteling was still there. So I turn on the machine and tried turning it more anticlockwise. The whining got stronger but no effect on the ratteling. So I turned it so the ratteling just went away.

I've tried holding the clutch and also putting in different gears but no difference in the ratteling sound. The sound is just like a chain slammering and the sound disappears at 1800rpm. It sounds when standin still and when riding under 1800rpms.

PLEASE, any suggestion on what to do is extremly helpful.

Also excuse any spelling mistake. I'm from Sweden!

All the best

// Martin Vestling

 

Your cct still ain't 100% imho

 

could it be the valves needing adjustment mixed with a stretched CC? or a sticking valve?

 

"The whining got stronger but no effect on the rattling. So I turned it so the ratteling just went away." - do you mean the whining went away? If you heard whining the balance shaft is set too tightly, you did right to loosen it.

Other causes of rattling:

- alternator / starter chain loose. Sorry to say it, but IIRC that requires the cases to be split. It has a tensioner, and that might be accessible with the oil pan off. Not sure, but others on the board will know. The fact that your sound is rpm dependent points to the chain or tensioner.

- alternator bearings bad. Not my first choice, bad bearings will make noise no matter what the rpm. They are easy to replace, and if you have a good dealer, inexpensive parts. You may not have to go to Honda for those bearings, by the way. Your local auto parts dealer may have the correct size.

Good luck. And welcome to the site.

 

it might be the rocker arm..

 

Is it possible that the CCT is replaced, but you are still using the old stretched out chain and worn cam gears? If so, maybe the CCT cannot adjust for the excessive play.

 

I agree. If the alternator chain tensioner is broken the rattle won't go away & it's a very nasty rattle. You'll think the motor is going to explode. Sounds more like the cam chain itself is worn. Is there any way you can make a recording of the sound so we can have a listen? May help. Also you can use a screwdriver like a stethoscope to help pin point the exact location of the rattle. Good luck & hello. Welcome to the site.

 

So, back here again after 2 weeks working. I wanna thank you all for your great respons! I haven't had any time to search my dear bike until yesterday so I started with a oilchange (and of course new filter). Nothing different in the sound. So I took the bike to a guy nearby who's got a reputation on beeing a good mechanic. He thought the noise didn't had anything to do with the valves needing adjustment. So I started reading as much as my brain could stand on this forum about all the thing you guys said. The only problem is that all of them seems like possible alternatives.

So, here I am again asking for you guidance. For you to be able to help me I recorded my machine for a short time and uploded the movie on youtube. I found it to be the easy way for you to hear the slammering noise. So if you have time please hear it, and if I made any wrong, posting a youtube-clip please tell me.

http://www.youtube.com/watch?v=zzvfd8_r0NY

So, the alternator, still the CCT/CC, valves, or any other ideas?

All the best

Martin Vestling

 

hmm seemed to me and I'm guessing .......maybe weak clutch springs
so the plates are grabbing and chattering ? Or a broken clutch plate
and or bad bearings .........seemed to be clutch side of bike.......

Posting UTube clips is okay anytime I believe