FJ29ER Posted July 15, 2020 Share Posted July 15, 2020 21K. Valves have been adjusted. 2500 miles ago Manual tensioner installed and adjusted correctly. 2500 miles on current oil change. 10w40 yamalube When cold starting my FJ there is 1 knock/clunk after about 20 seconds of running. I only heard it recently when I changed my routine in the morning by staying with the bike as it warms up. Usually I would start it and go inside for a few then come out and go. So I have no idea when it started. The first time I filmed it from the left side of the bike because I was thinking it was the starter getting stuck or something then disengaging. I did not hear it in the video but could in real life,and it sounded louder from the right side. So when I filmed from right side I heard it in both. My eyes darted directly to the exhaust when it happened so I am thinking it is coming from the rear transmission area. Any ideas? Goinng to try to film every cold start to see if I can get a better origin of clunk. In the video it is about 3.5-4 seconds in. It is faint. Link to comment Share on other sites More sharing options...
kilo3 Posted July 15, 2020 Share Posted July 15, 2020 Almost sounds like your headers expanding/adjusting due to heat. 1 Link to comment Share on other sites More sharing options...
FJ29ER Posted July 15, 2020 Author Share Posted July 15, 2020 37 minutes ago, kilo3 said: Almost sounds like your headers expanding/adjusting due to heat. Could be. I would think it would be a pop/crack kinda noise though. Not a solid clunk. But sound could be changing leaving the exhaust tip. Link to comment Share on other sites More sharing options...
duhs10 Posted July 15, 2020 Share Posted July 15, 2020 Just started mine and let it warm up just to compare.. didn't get that noise, but also harder to hear faint noises over the rumble of the Akro. I'm in agreement with @kilo3that it is most likely related to something expanding or adjusting to heat. Does it happen after startup 100% of the time? '15 FJ-09 w/ lots of extras... Fayetteville, GA, USA Link to comment Share on other sites More sharing options...
Supporting Member roadrash83 Posted July 15, 2020 Supporting Member Share Posted July 15, 2020 Sound like a slight exhaust leak to me. tighten up your head pipe and exhaust clamps if it really bothers you. He who dies with the most toys wins. Link to comment Share on other sites More sharing options...
FJ29ER Posted July 17, 2020 Author Share Posted July 17, 2020 On 7/15/2020 at 2:02 PM, duhs10 said: Just started mine and let it warm up just to compare.. didn't get that noise, but also harder to hear faint noises over the rumble of the Akro. I'm in agreement with @kilo3that it is most likely related to something expanding or adjusting to heat. Does it happen after startup 100% of the time? 100% time on cold start in the morning. and Every once in awhile if I go somewhere on my lunch. I started it yesterday at lunch and put my hand on the muffler/cat underneath and the head pipe and of course it did not do it. Yesterday morning I put my hand on the exhaust tip and did not feel any kind of clunk/crack. So I will further investigate and try to get better video. Maybe just record audio as well. Going to give it some love with oil change, air filter, throttle sync etc this weekend Link to comment Share on other sites More sharing options...
Supporting Member texscottyd Posted July 17, 2020 Supporting Member Share Posted July 17, 2020 Mine does something similar on initial cold start, and I suspect it’s something in the clutch/gearbox that releases as the oil warms up. The clutch has always been a bit noisy on mine, especially when it’s cold, so I haven’t been overly concerned about whatever is making that dull clunk. If you start it on the centerstand, watch the rear wheel to see if there’s any visual change (speed up/slow down of drag rotation, chain/wheel twitches in sync with the noise, etc) My FJ has about 19k miles, so similar to yours. 1 Link to comment Share on other sites More sharing options...
FJ29ER Posted July 17, 2020 Author Share Posted July 17, 2020 53 minutes ago, texscottyd said: If you start it on the centerstand, watch the rear wheel to see if there’s any visual change (speed up/slow down of drag rotation, chain/wheel twitches in sync with the noise, etc) My FJ has about 19k miles, so similar to yours. ooo good recommendation. It is always on the side stand when cold, but after lunch it is on the center. Yea mine sounds almost like a dry clutch since new. Slightly quieter after fresh oil but back within a few miles. Link to comment Share on other sites More sharing options...
Supporting Member texscottyd Posted July 17, 2020 Supporting Member Share Posted July 17, 2020 6 hours ago, FJ29ER said: ooo good recommendation. It is always on the side stand when cold, but after lunch it is on the center. Yea mine sounds almost like a dry clutch since new. Slightly quieter after fresh oil but back within a few miles. I’ll be interested in what you find. I may try and vary my startup routine to see if I can find any repeatable pattern. These bikes do seem to generate a lot of random mechanical noises, don’t they? Link to comment Share on other sites More sharing options...
FJ29ER Posted July 22, 2020 Author Share Posted July 22, 2020 On 7/17/2020 at 3:58 PM, texscottyd said: I’ll be interested in what you find. I may try and vary my startup routine to see if I can find any repeatable pattern. These bikes do seem to generate a lot of random mechanical noises, don’t they? Yes they do! So far after two cold starts on the center stand it has not made a peep....so we will see. 3 Link to comment Share on other sites More sharing options...
FJ29ER Posted July 27, 2020 Author Share Posted July 27, 2020 On 7/17/2020 at 3:58 PM, texscottyd said: I’ll be interested in what you find. I may try and vary my startup routine to see if I can find any repeatable pattern. These bikes do seem to generate a lot of random mechanical noises, don’t they? Still does it. Even on center stand. It is about 11 seconds in. I think I am going to try holding clutch lever in and see if there is a change. 1 Link to comment Share on other sites More sharing options...
skipperT Posted July 28, 2020 Share Posted July 28, 2020 This is going to sound like an odd question, but what if you turn the key on WITHOUT starting the bike, does it still make the click sound with the engine not running but bike powered on? Please wait the same amount of seconds to be sure.... -Skip Link to comment Share on other sites More sharing options...
iitywygms Posted July 28, 2020 Share Posted July 28, 2020 Mine does the same thing. I guess I will worry about it when it breaks. Keeping my eye on what you find tho. 1 1 Link to comment Share on other sites More sharing options...
Supporting Member dazzler24 Posted July 28, 2020 Supporting Member Share Posted July 28, 2020 1 hour ago, skipperT said: This is going to sound like an odd question, but what if you turn the key on WITHOUT starting the bike, does it still make the click sound with the engine not running but bike powered on? Please wait the same amount of seconds to be sure.... -Skip My thoughts as well. Is it an electrical sound? ...relay/solenoid? Link to comment Share on other sites More sharing options...
FJ29ER Posted July 28, 2020 Author Share Posted July 28, 2020 12 hours ago, dazzler24 said: My thoughts as well. Is it an electrical sound? ...relay/solenoid? 13 hours ago, skipperT said: This is going to sound like an odd question, but what if you turn the key on WITHOUT starting the bike, does it still make the click sound with the engine not running but bike powered on? Please wait the same amount of seconds to be sure.... -Skip Def not an electrical click. Unless these have some 80s ford starter solenoid on em that I have yet to find. After 3 starts with clutch in...it is significantly quieter but the knock/clunk still happens but you can hear it more pronounced. I thought this morning I heard a rising valve tapping noise followed by the clunk and it went away.... I had my helmet on already so I will try to get a video again to see if the audio is better with clutch in. I feel like it is acting like some autodecomp mechanisms out of dirtbikes Link to comment Share on other sites More sharing options...
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