Engine trouble... awaiting diagnosis

[jodyz_imp]

I took delivery of my CB at the end of March and now, with just under 1500 miles, the bike is back at the dealer awaiting a diagnosis to my engine noise. I took the bike back to the dealer at ~150, ~400, ~600 (first service), and now at just under 1500 miles, each time telling the service dept lead that there are noises coming from the motor that appeared to be intermittent. Dealer was unable to hear what I had been hearing since I purchased the bike, until Friday when I dropped the bike off after finally being able to localize the noise while parked. To me, the noise appears to be coming from the front, lower engine case right about where the oil cooler lines enter/exit the motor. Anyway, the dealer finally heard what I was hearing and they won't have a diagnosis until next week. I was told they'd be calling Honda to see if there have been any issues with the motor.

I've babied this bike since day-1. Short shifting and varying engine speed below 5k for the first 600 miles. Since the 600 miles service, I've opened it up a bit more, but I haven't hit 7k+ more than once or twice.

At first, either I, or the dealer, attributed the odd noises I heard to helmet vents (Shoei NeoTec) or my 8+ years away from riding. Coming off a 2002 Honda 919 (18k miles in 25 months of ownership), the air-cooled CB1100 was a different sounding bike to what I am accustomed to.

I hope to know more by mid-week.

[darmahman_imp]

What kind of noises are you hearing? From where exactly?

[jodyz_imp]

I took delivery of my CB at the end of March and now, with just under 1500 miles, the bike is back at the dealer awaiting a diagnosis to my engine noise. I took the bike back to the dealer at ~150, ~400, ~600 (first service), and now at just under 1500 miles, each time telling the service dept lead that there are noises coming from the motor that appeared to be intermittent. Dealer was unable to hear what I had been hearing since I purchased the bike, until Friday when I dropped the bike off after finally being able to localize the noise while parked. To me, the noise appears to be coming from the front, lower engine case right about where the oil cooler lines enter/exit the motor. Anyway, the dealer finally heard what I was hearing and they won't have a diagnosis until next week. I was told they'd be calling Honda to see if there have been any issues with the motor.

I've babied this bike since day-1. Short shifting and varying engine speed below 5k for the first 600 miles. Since the 600 miles service, I've opened it up a bit more, but I haven't hit 7k+ more than once or twice.

At first, either I, or the dealer, attributed the odd noises I heard to helmet vents (Shoei NeoTec) or my 8+ years away from riding. Coming off a 2002 Honda 919 (18k miles in 25 months of ownership), the air-cooled CB1100 was a different sounding bike to what I am accustomed to.

I hope to know more by mid-week.

What kind of noises are you hearing? From where exactly?

It sounds like a rattle or clunking. Also, the valves seemed loud to me since day 1. Again, I attributed that to my unfamiliarity with air-cooled motors. It may be my paranoia that makes me believe the valves are getting noisier as the rattling in the lower engine progressed. I really hope to know something before the end of next week.

[furious_blue_imp]

I took delivery of my CB at the end of March and now, with just under 1500 miles, the bike is back at the dealer awaiting a diagnosis to my engine noise. I took the bike back to the dealer at ~150, ~400, ~600 (first service), and now at just under 1500 miles, each time telling the service dept lead that there are noises coming from the motor that appeared to be intermittent. Dealer was unable to hear what I had been hearing since I purchased the bike, until Friday when I dropped the bike off after finally being able to localize the noise while parked. To me, the noise appears to be coming from the front, lower engine case right about where the oil cooler lines enter/exit the motor. Anyway, the dealer finally heard what I was hearing and they won't have a diagnosis until next week. I was told they'd be calling Honda to see if there have been any issues with the motor.

I've babied this bike since day-1. Short shifting and varying engine speed below 5k for the first 600 miles. Since the 600 miles service, I've opened it up a bit more, but I haven't hit 7k+ more than once or twice.

At first, either I, or the dealer, attributed the odd noises I heard to helmet vents (Shoei NeoTec) or my 8+ years away from riding. Coming off a 2002 Honda 919 (18k miles in 25 months of ownership), the air-cooled CB1100 was a different sounding bike to what I am accustomed to.

I hope to know more by mid-week.

What kind of noises are you hearing? From where exactly?

It sounds like a rattle or clunking. Also, the valves seemed loud to me since day 1. Again, I attributed that to my unfamiliarity with air-cooled motors. It may be my paranoia that makes me believe the valves are getting noisier as the rattling in the lower engine progressed. I really hope to know something before the end of next week.

ugh.. rattle or clunk from the lower front of the engine.. bearing going bad ? sucks about the downtime. I'll be curious what it turns out to be.

[Wereignsupreme_imp]

I just bought one as well, have about 300 miles on it. I noticed the same thing today, along with another issue I'll be posting about (I'm not very versed in mechanical things). I thought the rattle was possibly a loose gasket on the exhaust manifold, but that probably isn't it.

Hope you get good news from the dealer, I hope to take mine in soon as well.

[Guth_imp]

I've noticed a noise on my bike that I thought could be the valves. It can be heard as a clicking that occurs just as you begin to twist the throttle. After some research, I've come to attribute this to the fuel injection system. This is the first fuel injected bike that I've ridden and I have to admit to not being familiar with such things.

As far as the rattling goes, I'll be interested to hear what your dealer discovers. I noticed once when cleaning my bike that a small rock had become trapped down in the area where all four headers join. I wasn't expecting to find it there, but I could see how it might happen every now and then. Don't know if it's happened to anyone else here or not, but I could see where that could make some noise as well.

[Deanohh_imp]

I just bought one as well, have about 300 miles on it. I noticed the same thing today, along with another issue I'll be posting about (I'm not very versed in mechanical things). I thought the rattle was possibly a loose gasket on the exhaust manifold, but that probably isn't it.

Hope you get good news from the dealer, I hope to take mine in soon as well.

cam chain? Just guessing. You can use a length of small diameter hose as a "stethoscope" to pretty closely locate the noise.

[darmahman_imp]

This engine is so tight and quiet that I think it would be easy to mistake some noises as problematic that aren't. I would find it totally amazing and will eat major crow if even one, let alone 2 new Honda motorcycles here on this forum have an engine problem.

[jodyz_imp]

I've noticed a noise on my bike that I thought could be the valves. It can be heard as a clicking that occurs just as you begin to twist the throttle. After some research, I've come to attribute this to the fuel injection system. This is the first fuel injected bike that I've ridden and I have to admit to not being familiar with such things.

As far as the rattling goes, I'll be interested to hear what your dealer discovers. I noticed once when cleaning my bike that a small rock had become trapped down in the area where all four headers join. I wasn't expecting to find it there, but I could see how it might happen every now and then. Don't know if it's happened to anyone else here or not, but I could see where that could make some noise as well.

I had to pull over one day on my way to work because gravel had gotten on top of the exhaust pipes and was making a tremendous racket. It sounded like the entire crankcase had come apart. When I pulled over and put the bike on its side stand, a couple pieces of gravel fell onto the ground.

This engine is so tight and quiet that I think it would be easy to mistake some noises as problematic that aren't. I would find it totally amazing and will eat major crow if even one, let alone 2 new Honda motorcycles here on this forum have an engine problem.

I kept telling myself the same thing. I sincerely hope you're right, and it turns out to be nothing, but it has my dealer concerned enough (now that they have heard the same noise) that they intend to contact Honda on Tuesday.

[ridesalot_imp]

jodyz, a few general thoughts on the noise you are hearing. If the noise is coming from the inside of the motor, rattling sounds can be produced by a malfunctioning cam chain and its tensioner. It will be interesting to hear what the mechanics discover.

If the source of the noise is outside the motor it should be easier for you to find it by checking for tightness on all nuts and bolts which attach to either the motor or the frame.

A normal sound which you can hear is produced by the AIS (air injection system). During idle and low engine speed the AIS introduces air into the exhaust stream acting like an afterburner to burn any unburned fuel that reaches the header. This is accomplished using valves which are opened and closed by the CPU. The resulting clacking noise is audible. The AIS can also produce a popping noise on trailing throttle.

I believe that at idle and low rpm I can hear the cam doing its job. I would have to think of this as normal noise as well.