[Dave101]

Tapping, Ratteling, BB's in a can

lot's of people complain about rattle between 5500 to 6000 rpm.

Forgive me for asking, but when you say "lot's of people" are we talking about something like 8,000 of the 60,000 CBR250R units being produced world wide in 2011 by Honda Thailand or the 6 or 7 owners being vocal on this forum?

I have 400 miles on mine so far and haven't heard any of these noises (knock on wood). I grew concerned about this issue before I picked up my bike but could this issue be being blown out of proportion here? No disrespect, but those of you that have these noise problems are much closer to the issue and I defer to ask how wide spread have any of you discovered this to be?

If there was an issue I suspect I would be reading about it all over the net.

Anyone with engine noise mysteries care to state what month their bike was manufactured?

 

[Rossman]

Month made

Feb, 2011.

 

[Dave101]

Feb, 2011.

Thank you. That's a start. I tried to start a thread titled Month Made? a week or so ago to accumulate this kind of information and you and 2 others were the only ones that responded.

Rossman, you might be one of the earliest builds. Maybe if others start chiming in with their build dates and whether or not they have issues we might see a picture start to form.

Mine was March by the way, and no issues.

 

[250 Tom]

Seems strange some motors are doing it and others are not. Had the dealer look at mine and they agreed it was noisey. As I get more miles on the bike is seems to be not as loud. Maybe im just getting used to it. Maybe it will go away. We will see

 

[Dave101]

Tom

Note the exposed vin sticker on your frame on the gear shift side of your bike. Look in the top right corner of the sticker for the date of manufacture. What month was it made?

 

[250 Tom]

3/11

 

[Dave101]

Huh... same as me. Would you mind posting that in the Month Made? thread under general discussion - and I will get out of your thread and leave it be.

 

[CeeBeeArr]

2/11
Interesting indeed. I can definitely hear that noise in mine but the strange thing is, it is not consistent. It is torque related (or at least throttle related) and happens when it is hot.

For example, I was out for a morning ride and thought the engine had never sounded better. Went for another ride in the afternoon and noticed a distinct light tick that was louder under load and almost disappeared when cruising. Actually pretty scary because that kind of load related tick is usually not a good thing.

Then today, a morning ride, all good, and afternoon ride and there is the tick again. BUT, halfway home on the afternoon ride, the tick went away.

I am afraid to voice any suspicions but will say that this cannot be a serious problem because things that make that kind of noise tend to get worse pretty quickly.

But you can put me squarely in the 'Rossman' corner on this. It exists but I don't know what it is. The next thing to do is record it and calculate if it is a crankshaft speed noise or a camshaft speed noise or neither in which case it might be a timing chain noise or transmission noise.

 

[TheMente]

The bad thing here is that you can't check what it is while riding, and when you're off and could check you're not riding so the noise isn't there.
I am with ceebeearr when he sais it tends to get worse, but is seems just something metallic not properly fixed that, at certain rpm/torque/vibrations start ticking.
I don't feel it coming from the engine, anyway.
Someone should take it on a dyno and record it with a camera

 

[Carbonado]

Black ABS 2/11
I have the engine rattle at about 5500 rpm. I don't hear it when I use earplugs so a proper survey would require everyone to listen without the earplugs.

 

[Rossman]

Dyno

Someone did post a dyno graph on here, and it looks as though our bikes are putting out the most torque at 5500-6000 RPM, so there could be a direct co-relation. Like I said before, I've still got my head open and have squarely inspected anything. My gut still tells me it's noise related to the rockers skating back/forth, or even the dowels that hold the rockers in place seem to be hitting the caps on the side of the motor (bolt caps). That being said, my components look perfect though. No play in roller bearings, no cam scoring, etc. Something that we might not be able to see though, and it could be, is a light form of piston slap.

 

[CeeBeeArr]

... Something that we might not be able to see though, and it could be, is a light form of piston slap.

This crosses my mind too except that it comes and goes on my engine. Also, in the old days, piston slap tended to happen more when cold. Maybe the cooler thicker oil cushions it. I am running 10W40 because I was curious if it would make a difference but no difference that I can hear.

I guess somebody needs to blow one up and find out what broke...

 

[Redline]

it comes and goes on my engine.

Yes, strange. Same on mine.

I'm still not fully convinced it's from inside the engine.

I changed to a cheap full system pipe for two days and the bike was visibly vibrating more (windscreen and mirrors), and the buzzy rattling sound was worse than usual.

Perhaps it's some part around the front of the bike that vibrates at those harmonies.

Anyone strip off all the plastics and dash and ride it naked?

 

[Redline]

btw, when mine first started at around 500km and then got worse by 1500km and got the dealer to check it out, most of the rattle was coming from one of those little convex mirrors that you stick on the original mirrors to get rid of the blind spot. The actual mirror had come loose and was buzzing around in it's case at those rpm.

Took 'em off, but was still left with the much lighter buzzy/rattle that many suffer from.

Perhaps there's some component attached that becomes ever so loose around the front area that vibrates.


Someone really needs to strip the bike bare and test it with nothing but the engine and the frame.

 

[TheMente]

I was suggesting to put it on a dyno and record it with a camera while running through gears to have a visual check of what can vibrate at that rpm.
I am still not convinced it's IN the engine, but that it's AROUND that. I clearly hear the engine running smooth, when I ope throttle and when I leave it, but the vibrating noise is there: that's why I am not complaining.

Second thing: the vibrating sequence is constant: if it was rpm-related, should have varied through rpm intervals: starting slower than becoming faster at higher rpms. I can't recall anything like that.

 

[Rossman]

Update

So here's the latest. My new shims came in for the exhaust, and I put them in. They now measure exactly .011 as required. Take the bike out for a ride, and the rattle seems to have diminished at the 5200-5800 rpm mark, but is still there a bit at 6K. It's definitely made a difference. Also, when my bike is idling now, I can hear the tappet noise from the valves whereas I didn't before when they were tighter.

 

[Panamera]

dealer checked mine out.
agreed there is such a rattle.

said that is exactly in the middle of the RPM range, and the engine just isnt happy there and i should above that RPM range around 5.3k RPM. as the engine is wanting more load and pretty much what the gentleman above said about it having the most torque there.

said i shouldnt worry and if anything goes wrong they know about it.

it is rather annoying though when i cant hear the engine noise over it

 

[Redline]

That sounds pretty vague, and is a crap excuse tbh.

That the engine isn't happy at that RPM so makes a loud, buzzy, annoying rattling sound.

Doubt Honda will be printing that in the next broucher.

And still doesn't answer what exactly it is.

That's crap feedback from a dealership tbh, and it should be reported to Honda HQ that they're dealers are telling customers that the new bikes are making loud, shitty noises because the engine isn't happy at particular RPMs.

Which happen to be in the middle of the rpm range so hardly fucking easy to avoid.

 

[CeeBeeArr]

dealer checked mine out.
agreed there is such a rattle.

said that is exactly in the middle of the RPM range, and the engine just isnt happy there and i should above that RPM range around 5.3k RPM. as the engine is wanting more load and pretty much what the gentleman above said about it having the most torque there.

said i shouldnt worry and if anything goes wrong they know about it.

it is rather annoying though when i cant hear the engine noise over it

The dealer would get more respect (from me at least) if he said, 'I hear it but I don't know what is doing it. Thank you for bringing it to our attention. If we learn anything we will let you know; if you learn anything please let us know.'

When these people literally make up these excuses, and that is all they are, it diminishes them. There is no particular reason for a dealer to know every answer about their motorcycles and this is a pretty obscure problem. But to pretend you know the answer to everything. Well, we know about those kind of people.

Also a bit hard to believe that the engine is 'isn't happy' at the point in its power curve that is the sweet spot (IMHO). Maximum torque is a sign of an engine being in a 'happy place' I would think.

And gosh, if that is the exact middle of its RPM range, can I use it a 500rpm? My engine seems to like 3000RPM or above so, let me see, that puts the rattle exactly in the most usable range for typical riding.

Other than the rattle though, the engine seems great so I remain hopeful.

 

[somebody5788]

As far as I can tell the noise is not the engine but more likely something attached. It's either something like a clutch cable end rattling in it's holder or something similar. It's just that those RPM happen to be the most vibration prone. I can hear my valves and they aren't making the noise.