ApolloMozart Posted July 21, 2014 Share Posted July 21, 2014 Gents, may I pick your brains (and ears)?Lately my new CBR developed a rattle from around the engine area. I took it to the dealer and they had a ride but (maybe the age of their test pilot is at fault) said they can't hear the rattle. I tried to describe it as much as possible and they said they'll order a new chain tensioner, as this is probably what's causing the rattle.While waiting for the new tensioner, I decided to record the sound of the rattle and share it with all of you, in the hope that someone may either confirm the tensioner theory or come with some other plausible explanation.I'm more inclined to think that it's something loose somewhere.The rattly is more prominent when the engine is hot. The easies way to "find" it is to go at around 30 mph, steady gas, in third gear. Under power all is nice and silent. As soon I roll off the throttle a bit - here comes the rattle.I uploaded the sound to - please have a listen to it and let me know what do you think.Thank you!"> Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted July 21, 2014 Share Posted July 21, 2014 sounds fine to me i would let the dealer change the tensioner and see what happens then as they might of had a couple fail so are doing it rather than wait hoping it is ok Quote Link to comment Share on other sites More sharing options...
ApolloMozart Posted July 22, 2014 Author Share Posted July 22, 2014 This morning the rattle was noticeable louder. I have the feeling it comes from somewhere under the tank/top of the engine.The demo bike I tried at the dealer did not have this rattle.Maybe is harmless, but it spoils the enjoyment from riding the bike...I'll go along with tensioner replacement, but if it does't help I'll take the tank out myself and investigate. Quote Link to comment Share on other sites More sharing options...
Grumpy Old Git Posted July 22, 2014 Share Posted July 22, 2014 Sounds similar to a 'tappet rattle' - When did you have the last top-end service (valve shims, etc.)? Quote Link to comment Share on other sites More sharing options...
ApolloMozart Posted July 22, 2014 Author Share Posted July 22, 2014 The bike is new, only done 650 miles. The valve clearance check is only scheduled at [strikeout]8000[/strikeout] 16000 (edit) miles.It started from day one, after about 10 miles of riding. It was barely audible then, so I thought it may be something normal during running in time. But it got louder and louder.If the tensioner does not make a difference, I need to find a way to make the dealer to look into it properly. They seem to be "unable" to hear the noise. The chap took it for a ride and said all is normal, can't hear anything wrong. Quote Link to comment Share on other sites More sharing options...
Grumpy Old Git Posted July 22, 2014 Share Posted July 22, 2014 Show them your recording - Quite obvious from that. Quote Link to comment Share on other sites More sharing options...
ApolloMozart Posted July 22, 2014 Author Share Posted July 22, 2014 Went down to the parking and played a little with the tensioner - took the little covering bolt and used a screwdriver to pull/release the tensioner. I'll see if this makes a difference in the evening. Quote Link to comment Share on other sites More sharing options...
Lumor_uk Posted July 22, 2014 Share Posted July 22, 2014 leave it alone if it's under warranty let them sort it out. they will tighten everything up when they do the chain tensioner. Quote Link to comment Share on other sites More sharing options...
Rik398 Posted July 22, 2014 Share Posted July 22, 2014 I am sure that some new bikes generally have a cam clearance check quite early on in the service schedule. I think in many bikes they check them at first service and from then they are ok to 16k or whatever the next interval is? Makes sense to me as with a new engine and everything starting to be run in it seems likely that the clearances would alter, and then settle down more later on. Do you have a service book for your bike? It may mention cam clearances in the first service. Don't tinker with it yourself. I am sure they would not need much of an excuse to wiggle out of any warranty work. Quote Link to comment Share on other sites More sharing options...
ApolloMozart Posted July 23, 2014 Author Share Posted July 23, 2014 The old CBR500r I had indeed was checked at 600 miles for valve clearance. For the new bikes (CBR650f, CB650f) they dropped this check from service schedule so the first valve check is at 16k.The sad thing about all this is that I am not enjoying the bike that much anymore... Feel like I've been sold a broken bike. Quote Link to comment Share on other sites More sharing options...
Cpt_Tact Posted July 23, 2014 Share Posted July 23, 2014 I have only ever seen the top end rattle and go pop once on a Honda CBR600RR and it only had 8k on the clock, 3 garages were all certain it was the cam chain/ tensioner and eventually one of them decided to strip the engine to work it out once and for all and low and behold the damage was pretty bad to the point they just bought a replacement to drop in. Your video just doesn't sound at all right, I'd play them the sound and take one out on the back and then when it starts you can shout at him and you can point out exactly the sound rather than some guy trying to guess what sounds right and what doesn't. Quote Link to comment Share on other sites More sharing options...
Rik398 Posted July 23, 2014 Share Posted July 23, 2014 At the end of the day, if you're not happy with it then they will have to look into it. Sounds like they are doing an ok job at the moment, start with the simple things (chain tensioner) and work up. Getting someone to go pillion or handing over the recording does sound the best plan of action to aid in getting them to hear what is going on. Has it had its bolt tourque check yet? Another thing that often happens in the first service. They check tightness of important bolts and things, could be something has come a little loose. When is its first service due? You could get them to give it its first service a little early along with the chain tensioner and see if that eliminates anything. Assuming new bikes these days still have an early first service of any kind? Quote Link to comment Share on other sites More sharing options...
ApolloMozart Posted July 24, 2014 Author Share Posted July 24, 2014 First service is at 600 miles. I don't think they've checked any bolts or anything. They said first service is just to change the oil. Although the guys from Honda look like they're trying to help, but when I'm there, they seem to just try to find an excuse not to do more. I complained about the rattle and one of them went for a ride, came back and said he can't hear anything. I insisted they do something, and he said let's order a chain tensioner.I think the rattle is not from inside the engine. First of all it does not change with rpm. Second it only appears when the engine is not under load. I think something touches the engine somewhere. When the engine is loaded, it moves slightly, increasing the gap and the rattle goes away. When engine is idling or not loaded, the gap decreases and rattle appears. And lastly, it's the way the rattle developed. It started when I went over a speed bump, before that it was all quiet. At the beginning it was barely noticeable, but then it got worse and worse. Maybe something is getting loose and the engine moves more freely... Also if it was the tensioner, it should be louder on the right side of the bike, as it is there. In my case the sound seem to be coming from the top of the engine, under the tank.I tried to explain all this to the honda people but they just didn't want to listen to my thinking. It's the tensioner according to them. Quote Link to comment Share on other sites More sharing options...
Mr Fro Posted July 24, 2014 Share Posted July 24, 2014 Your analysis makes a lot of sense, maybe an engine mount has slackened off a bit... Quote Link to comment Share on other sites More sharing options...
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