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Discussion Starter #1 (Edited)
Hello, CBR 900RR

My newly installed motor is making this light noise while the clutch is out. If I pull the clutch in it stops making the noise. Now my last motor made a similar noise at first, and I bought a manual cct. Never installed it b/c the motor then started to knock. Spun bearing. I am hoping that it is the manual cct that needs adjusting, as i did install it in the new motor. I've ridden it only like 500miles since installed. I guess it was sitting for a while before I bought it. Do you have to break in a motor that has been sitting as you would a motor that is new? Does that not matter? Is it fine to take it up to 14,000 rpm? It's a 1999 motor btw.

I was also thinking of changing the oil tomorrow after I take it to the shop to get it revised and the cct adjusted. Is it recommended to change the oil? I think that I should just to be safe and clear any soot that may have been in there.

I am also thinking that I can look at the oil and see if there are any little flakes of aluminum as well, which may be an indicator of a big problem.

Maybe I'm blowing it out of proportion. I hope so. :hmm:
 

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Discussion Starter #2
Re:900RR Motor Noise!

So i was reading posts here and it seems like i should look for a silvery fuild in addition to lil flakes/what not.

Also it may be the clutch basket.

Another interesting thread mentioned it may be the carbs that need adjusting.

Seems like there could be a vast variety of things that could be the prob.


I will post a video tomorrow.
 

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Hello, CBR 900RR

My newly installed motor is making this light noise while the clutch is out. If I pull the clutch in it stops making the noise. Now my last motor made a similar noise at first, and I bought a manual cct. Never installed it b/c the motor then started to knock. Spun bearing. I am hoping that it is the manual cct that needs adjusting, as i did install it in the new motor. I've ridden it only like 500miles since installed. I guess it was sitting for a while before I bought it. Do you have to break in a motor that has been sitting as you would a motor that is new? Does that not matter? Is it fine to take it up to 14,000 rpm? It's a 1999 motor btw.

I was also thinking of changing the oil tomorrow after I take it to the shop to get it revised and the cct adjusted. Is it recommended to change the oil? I think that I should just to be safe and clear any soot that may have been in there.

I am also thinking that I can look at the oil and see if there are any little flakes of aluminum as well, which may be an indicator of a big problem.

Maybe I'm blowing it out of proportion. I hope so. :hmm:
I can't determine if you mean a newly built motor or a secondhand motor that is merely new to you?
Sounds like normal noise from the clutch basket damper springs. I assume the clutch basket is not new? The CCT will not stop this noise.
No, you do not have to run-in a motor that has been sitting, although you should change the oil to remove any condensation and lubricate the cylinders before turning the engine over. I think up to '99 they still have iron bores, if the intake and exhaust ports were not sealed during storage there's a strong risk of rust in the bores which is likely to eat the rings fairly quickly.
No, it is not fine to take it 14,000RPM unless you want to bend some valves. Peak power is around 10,500RPM so there is no reason to be revving it above that point - ever.
Do you mean that you've done 500 miles on the oil that was in the engine when you bought it?
 

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Discussion Starter #4
The motor is under a load when it's high in rpm, I'm not reving it w/o a load on the motor.

500 miles since new oil and motor has been installed. No oil was in the motor, but there was a little white liquid that had accumulated. It is thought to have been from condensation. That little fluid was drainned.

Yes the cylinders were lubricated w/ new oil before we started it.

I put new oil into the motor. It ran clear caramel like for a while. I think it is darker now.
 

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The motor is under a load when it's high in rpm, I'm not reving it w/o a load on the motor.

500 miles since new oil and motor has been installed. No oil was in the motor, but there was a little white liquid that had accumulated. It is thought to have been from condensation. That little fluid was drainned.

Yes the cylinders were lubricated w/ new oil before we started it.

I put new oil into the motor. It ran clear caramel like for a while. I think it is darker now.
If it's under load then I doubt it's possible to rev it to 14,000RPM since the limiter will come in well before then.
I can't see any reason to drain the oil at 500 miles other than for your own peace of mind. You can put it back in again if it's fine.
 

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And I just remembered that somebody told me the 900RR went to aluminium bores in either '96 or '98 but I can't recall which.
 

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Discussion Starter #9
BR, you crazy son of a b*tch! I like your style man! AWESOME! And does that benefit me b/c they wont rust? Hummmm....i hope I'm freakin out b/c I got a steering stabilizer and this motor pulls! This bike is...i cant explain it. Bliss. I'll build it again if it breaks. I don't care! :rotfl:
 

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BR, you crazy son of a b*tch! I like your style man! AWESOME! And does that benefit me b/c they wont rust? Hummmm....i hope I'm freakin out b/c I got a steering stabilizer and this motor pulls! This bike is...i cant explain it. Bliss. I'll build it again if it breaks. I don't care! :rotfl:
If the bores are plated then they won't rust. But if the rings aren't chrome then they can still rust if water gets into the cylinder.
The Blades are good fun alright :)
 

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Discussion Starter #11
so i went to two different shops.

both said it sounds good nothing wrong.

my buddy mechanic's coming by later to tripple check. guess i'm tripping.

i added a little oil. it was on the low end of the glass.

have to wait and see. I guess just ride it no. :)
 

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Hello, CBR 900RR

My newly installed motor is making this light noise while the clutch is out. If I pull the clutch in it stops making the noise.
I had a similar situation, mine had a light noise that would stop if I pulled the clutch in or had it under load, wouldn't knock any other time and it still had a spun bearing, although it was barely spun and the crank was machinable.

Not saying that is your problem, but you may want to put forth the effort to actually find the location of the noise. They have automotive stethoscopes, but a broom handle cut to 12-16 inches will do the trick too. Cup one end in your hand, put it to your ear and start placing the other end around the engine until you find it.
 

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I had a similar situation, mine had a light noise that would stop if I pulled the clutch in or had it under load, wouldn't knock any other time and it still had a spun bearing, although it was barely spun and the crank was machinable.

Not saying that is your problem, but you may want to put forth the effort to actually find the location of the noise. They have automotive stethoscopes, but a broom handle cut to 12-16 inches will do the trick too. Cup one end in your hand, put it to your ear and start placing the other end around the engine until you find it.
A bearing knock that stopped when you disengaged the clutch?
Does it still make the same noise now with the same clutch basket?

When diagnosing engine noises hold a handful of rags in the muffler outlet to eliminate the exhaust noise.
 

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A bearing knock that stopped when you disengaged the clutch?
Does it still make the same noise now with the same clutch basket?

When diagnosing engine noises hold a handful of rags in the muffler outlet to eliminate the exhaust noise.
It's really hard to determine for sure now with the engine in pieces on my workbench :rotfl:

But the noise was coming from the bottom of the block on the left side, right where the spun bearing had been, no noise on the clutch side and it would stop when I disengaged the clutch in neutral or put the engine under a load. It was kinda strange in that the big end was loose only through part of it's travel when I tore into the block and checked it, so maybe that was a factor. You did just give me an idea though, I might install the old basket in the used engine I have coming just to see if it was the bearing or the basket.

Good call on the rag idea.
 

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Balancing the carbs or throttle bodies can make a huge difference on engine noise at idle with the clutch out. The reason is that the crankshaft pulses are not even and it shakes the clutch basket, kind of like a Ducati dry clutch. I had a 6 cyl CBX that made a ton of clanging and banging at idle. I balanced the carbs which were way out and it was like a new engine. Even as you turn the adjustment screws and watch the vac gauges even up, you hear the engine go quiet. This makes the cam chain and clutch basket stop rattling.
 

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Balancing the carbs or throttle bodies can make a huge difference on engine noise at idle with the clutch out. The reason is that the crankshaft pulses are not even and it shakes the clutch basket, kind of like a Ducati dry clutch. I had a 6 cyl CBX that made a ton of clanging and banging at idle. I balanced the carbs which were way out and it was like a new engine. Even as you turn the adjustment screws and watch the vac gauges even up, you hear the engine go quiet. This makes the cam chain and clutch basket stop rattling.
This is definately true, keeping on top of engine maintenance will make the engine sound much smoother.
 

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Discussion Starter #19
YUP. I THINK I MAY HAVE TO TAKE IT TO THE DOCTOR AND HAVE THE CARBS SYNCRONIZED. MY FRIEND SAID IT LOOKED LIKE IT HAD A JET KIT. IT'S RUNNING LEAN AS IT BACKFIRES! POP!:devil:pOP!
 

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YUP. I THINK I MAY HAVE TO TAKE IT TO THE DOCTOR AND HAVE THE CARBS SYNCRONIZED. MY FRIEND SAID IT LOOKED LIKE IT HAD A JET KIT. IT'S RUNNING LEAN AS IT BACKFIRES! POP!:devil:pOP!
Popping and backfiring are two very different things.
Popping can indicate a lean condition but it's most commonly due to air leaks in the exhaust system.
 
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