I have a '99 F4 and its currently making a odd sound. When the bike is first started and is warming up there are no odd noises...at least none I have heard so far, however, once the bike is warmed up I can hear a knocking sound...very faint at idle but more pronounced at higher RPM's. The higher the RPM the faster the knocking. I have heard a few possible causes but I was hoping someone else would have some ideas. I have heard it could be a lean fuel mix, carbon buildup, valve clearance. The bike currently has 30,000 miles on it, valves were adjusted by a dealer at 20,000. Any thoughts??? If you think its one of the above mentioned problems, any ideas on solutions, or possibly ways to eliminate causes? Would a faulty CCT cause this sound? Ive heard those seem to be a common problem among CBR owners.

 

What no one is up at this un-natural hour that has the answers to my problems?

 

Everyone seems to be an expert on things till I ask a question. Would a sound byte help? This is beginning to get annoying, I'm starting to think im gonna have to go talk to the dealer since I dont seem to have a mechanic friend around to ask. Perhaps ill just go enroll myself in UTI's program and learn the ins and outs of the whole damn bike.

 

I'm thinking cam chain tensioner but without hearing it......

 

I'll post a sound byte when I get a chance..what gets me is that it doesnt make any noise when its cold, only after the temp comes up....that i can hear anyhow.

 

my '95 F3 is doing something similar, at least by what you described. It sounds like a loose bolt/rattle but it only seems to happen when the bikes warmed up and is worst at idle (highest engine vibration). I was told its the cam chain tensioner which im replacing as soon as it comes it. Ill let you know what happens, do post a sound byte if you get a chance. Ill do the same if the weather isn't too nice adn im not in too much of a hurry .

 

My guess is CCT. I have an 02 f4i and just last week changed the CCT and it cured my noise which was a similar noise to what you are describing. Does it seem to be coming from the right top side? You can take a long screwdriver if you don't have a stethoscope and put the handle to your ear and the metal end on different parts of the engine to attempt to locate where the noise is actually coming from. If it is the CCT, it was a tedious process to change out, but with average skills, you can do it yourself. Good luck and keep us posted.

 

try cam chain tensioner anyway my f4 rattled at 3000 to 5000rpm AND on the backoff from a high rpm sprint (sounded like a big end bearing thumping) it was just the CCT what a relief i tell you~! crossy

 

Definitely CCT or you might need to re-lash your valves. They may be fine at cooler temps (i.e. startup/warmup) but tolerances change when it gets hot. Thats where I would start anyway. Keep us posted....

 

Well I ordered a CCT. Hopefully that will solve the problem. This is starting to **** me off....its 70 degrees outside and my bikes hiding from the sun in the garage.