So...I just picked up a used CBR929 for 3900$, and as i was in the process of driving it back from the buyers house, it made a loud mechanical clatter...any ideas as to what this could be? The bike has 36k miles on it, is incredibly clean, was garaged all it's life...it doesn't seem like it should be having any problems. The guy is the original owner, has multiple bikes, seems to take really good care of all of his stuff...could it be something as simple as a failed cam chain tensioner? There was a definant loss of power when the sound started.

Thanks!

 

Did it make that noise when you test rode it? Or before you purchased it? How about the gas in it? Bad gas will make it pre-detonate and cause a pinging sound, like in cars when the timing chain rattles. How are the valves? Sometimes, I've heard of the cam lobes pitting. Not like craters, but like little volcanoe structures and the valves don't have the correct lash because of it. Let the section know what you find out. Everything helps. Good luck.

 

No, no noise when i test rode it. It developed it and immediately lost power, about 50 miles into my 70 mile ride home. The clatter follows the rev range, seems to be sync'd to reving...According to the buyer, it was coming up on it's next valve adjustment in about 6k, and last time it had been adjusted only a few were out.

This is not a pinging noise, or the sound that a cam chain makes when it's smacking into it's runners, it's a very loud metal on metal type noise.

 

So the problem turned out to be a loose spark plug...it had backed out of the threads because it hadn't been torqued down correctly, and was causing it to not fire on the #2 cylinder as well as being loud as hell. The bike is fine now, with everything installed and torqued correctly!

 

good to hear it was a cheap and easy fix.

 

tell me a little more about this. same thing just happened to me yesterday. everything seemed all cool and when I pulled out ofa parking lot, POW and hella noise as well as a huge loss in power. turned out to be the same thing as happened to you.

the reason Im asking for more info is because is sounded like my valves were ticking a little in the weeks before this happened. did that happen to you? now I'm debating a valve check while the airbox and tank is off. I know I should do it but everything I hear and read on valve checks on hondas is that they are usually dead on. I'm still a little concerned about the ticking noise though. if you had a ticking before the incident, did correcting the problem cause the ticking to go away?

thanks for any info.

 

when is a good time to change the plugs?

 

I've had the ticking noise for a few months but only around 2500-3000 rpm's but no power loss. I was thinking it just needs a valve adjustment.