Hi all,

I'm new to this board but not particularly new to CBR's. I have a 1996 CBR900RR with 24k miles that I've owned since new. Great, fast reliable bike that I've only had a few problems with in 9 years.

But I am concerned about an engine noise that has been developing, a little hard to describe, the noise occurs when the engine is cold but not upon immediatly start up, it occurs during engine warm up period until completely warmed up. You hear it when holding a steady RPM and let off, it's kind of like a metalic loose or rattling sound when you let off the throttle like when approaching a stop sign. I think it pretty much goes away after fully warmed up.

I replaced the cam chain tensioner a few years ago when the engine was making some noise (I can't remember exactly what that particular noise was like) and luckily it solved that problem. I guess I'm really hoping that it may be the cam chain tensioner again. I'm going to try to turn the cam chain tensioner lifter and see if that does anything, or maybe change it again in hopes that may be the problem.

Does anyone have any other recommendations??? Any help is very much appreciated.

Thanks

 

Could be the CTT again, hard to work with noises. we all seem to interpret them different.

 

Anubis,

Thanks for your response. I'm assuming you mean the "Cam Chain Tensioner" when you say CCT. I haven't had a chance to mess with it yet, but am still hoping that it is the cause. Have you, or do you know people who have replaced these more than once on the 900RR? I guess I'll find out when I replace it. Thanks again for your help...

Brian

 

Most of the poeple that i know that ride Hondas have had to replace their cam chain tensioner at least once. I am getting ready to do it on my 97 the guy that owned my bike before me must have never heard of the word maintanace because I bought the bike at 20K and I have only put about 2 K on it and in that time every known problem that you have to take care of up to 20 K I have had. With that being said I have heard good things about the APE manual cam chain tensioner. I am thinking about going to this as apposed to the OEM one. Has any one used one. If so would you recomend it? As always help is appreciated!!

Thanks

Casey

 

Tbone,

Thanks for your help. I didn't know there was an aftermarket replacement cam chain tensioner available. I'm usually afraid to use aftermarket parts since I've had bad experiences doing this with cars in the past, but it's definitely worth a shot. Good choice to do research on it first.

What else have you had to replace on your CBR?

Brian

 

So far i have had to replace.... Tires, brakes, fork seals <have not done that yet, chain, sprockets, front and rear wheel bearings, checked valve clearances (i thought the noisy cam chain tensioner was a valve tick) but it wasnt i have narrowed it down to an exhaust leak on cyl 4 and a spent tensioner. Right now I have a new air filter in the mail. I am still working on my ign lock but that wasnt the previous owners fault it was the jack *** that tried to steal her!!! Thats where I am at now I noticed that the pet **** doesnt seem to shut completely off. So...... i will probably replace that here pretty soon as well!

 

T-Bone,

That is a lot of stuff, but it sounds like your taking your time and doing it right. Some advice on the drive chain... I replaced mine on my 1996, and the chain was different that year, a unique size like 525 or something. The dealer was insisting on selling me the wrong chain until I proved him wrong. So make sure you know the correct chain for the bike. Good luck with everything.

Brian

 

The APE cam chain tensioner is awesome! I've heard it actually adds horsepower! Oh wait, I'm the one who said that. Anyway, call me and I'll sell you one.

 

hi , i have one the service manual, i currently do not have it with me but i remember it describing the problem that u are describing with the rattling noise when it is cold. it says something about the pistons and how it is just expanding, and when the engine is warm , it would go away.

 

Thanks all!

I replaced the cam chain tenshioner today and (knock on wood) it seems the engine noise is gone! It is much colder outside than the last time I ran the bike but I don't think that should enter into the equation.

Similar to last time, when I remove the cam chain tenshioner I couldn't really find anything wrong or unusual about it... It may be just a lousy design. It has been only 2-3 years and about 3,000 miles since I replaced this thing before, go figure...

But thanks again for your help and suggestions.

Brian