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having difficulty seeing how detonation would be caused by the octane level
recommended by honda.. mine has been running on 91RON [= 87PON apprx]
no ethanol for about 18mths with no pinging or detonation, completely stock
and also with a lv evoII slip-on the last 3 - 4 mths..

petrol may be contaminated, esp with water if it includes ethanol..
another factor possible being lugging the engine, such as throttling
from low rpm in higher gears thus overloading the engine causing
increased pressure.. over-lean fuel mix is a factor, together with
high temperature.. i have a slip-on exhaust which should increase
flow to some extent, yet without pinging [or detonation] in over
3 mths, same routes, same petrol etc..

reported rev range of around 5500rpm sounds high enough revs
to preclude lugging the engine, unless this is in top gear
and is part way thru the acceleration sequence, not the start..
it would be interesting to see if using higher rev ranges
for the same gears, and not, starting power uptake
at low revs, has any effect on these 'rattling' engines..

this [pinging, detonation, pre-ignition] should be apparent
to honda mechanics.. interesting if it does not occur
when the same bike is ridden by a honda mechanic..

also interesting if those using richer fuel mix/mapping
with power commanders etc have eliminated their 'rattle'..
 

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opps sorry new to forums ..was refering to 5k engine rattle was on page to sign up to get enough votes ..dont know why it posted here??
 

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Just use a higher grade of fuel, i.e. premium and watch it magically go away.
 

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I'll bet my cbr made exactly the same noise as the other 100,000 cbrs.

its just I never lugged it at 5,500rpm killing the engine so I never noticed it.
 
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this subject has been well aired now, but on responses,
if my bike j[18mths daily riding] engine started to 'rattle'
as in making unusual mechanical noises, it would be
straight into the mechanic for an expert opinion..

given that various things might make a 'rattling sound'
aside from untypical engine noises, first response must be
to go over your motorcycle to ensure all fasteners etc
are secure and not allowing anything to 'rattle'..

members have reported loose fairing panels, engine mounts,
instrument area and foreign objects in fairing belly pan..
ie, as the causes of/solutions to their 'rattles'..

first thing i did after getting black beauty [used, under 600km]
was to go over her checking all fasteners for security..
[had no idea then of any, 'rattle' etc]

if members have gone over their bikes for fastener security etc,
and still have worrying 'engine rattles' then next response
must be to seek advice from a honda mechanic..
 

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I'm not so sure that it's an engine rattle. I have it too but I think it's coming from someplace else. The rattle doesn't sound very mechanical. It sounds like something is slightly loose and starts rattling when vibrations hit a certain frequency at around 5.5K rpms. If it was the engine I would think it would be rattling through the entire rev range but I am not qualified to state that as anything but theory. An uneducated guess if you will.

It's possible that the console unit may be loose but there's a lot of stuff that has to come off to really check it. There are too many possibilities to list. My left side fairing wasn't snug. After snugging it up the rattle got better but not gone completely so I might be on the right track. I check a couple things every chance I get.
Hi just answering to your quest.
I am the owner of a brand new cbr 250r 2011 model but i bought it last january and so far the clock reads 6500 km almost. this bike from the start always sounded like a metall tin with some nail in it. It is the engine that rattles in mine and took me sometime to understand what was wrong with it. I took it back to the dealer where i bought it at first but the did not do much and said to me that it was normal.
I insisted to find the problem myself since i have a little mechanical knowledge and i had the feeling that the engine oil pressure was too low. Since this bike has not got an engine oil alarm light on the dash to be sure i was right i checked the engine myself.
I have removed the engine oil pump from the engine which is located on the right side of the engine just next to the clutch and removed and changed with a brand new an oil pressure relief valve wich is located behind the oil pump and attached to it (i paid 33 euros for it from the honda dealer) close the right cover of the engine and assembled it in reverse to start the engine again. Once everything was ready i started the engine and went for a test ride. Result is the it is now a new bike, the rattle is gone no more little vibrations on the handle bars quite engine and top speed of 160 km per hour. Before this little service it only reached a top speed of 150 kmh. This little valve that i changed it was jammed open which means that engine did not received enough oil to the bearing and shims and therefore it was like it had more friction on them that resulted in the engine to turn slower and make a hell of a metal noise. luckly the engine did not break but i think it went close. This was for my bike but that does not mean that yours has the same problem. Just an advice it could be something to look into it. For the rest the bike is perfect and i have never had any other issue with it i think it is worth the money i paid for it and the quality of the components is very good i hope this coul be helpful for you
all the best
 

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sounds like a easy fix. Did you need any special tools to get to oil pressure relief valve?
Thanks for the info
 

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Hi just answering to your quest.
I am the owner of a brand new cbr 250r 2011 model but i bought it last january and so far the clock reads 6500 km almost. this bike from the start always sounded like a metall tin with some nail in it. It is the engine that rattles in mine and took me sometime to understand what was wrong with it. I took it back to the dealer where i bought it at first but the did not do much and said to me that it was normal.
I insisted to find the problem myself since i have a little mechanical knowledge and i had the feeling that the engine oil pressure was too low. Since this bike has not got an engine oil alarm light on the dash to be sure i was right i checked the engine myself.
I have removed the engine oil pump from the engine which is located on the right side of the engine just next to the clutch and removed and changed with a brand new an oil pressure relief valve wich is located behind the oil pump and attached to it (i paid 33 euros for it from the honda dealer) close the right cover of the engine and assembled it in reverse to start the engine again. Once everything was ready i started the engine and went for a test ride. Result is the it is now a new bike, the rattle is gone no more little vibrations on the handle bars quite engine and top speed of 160 km per hour. Before this little service it only reached a top speed of 150 kmh. This little valve that i changed it was jammed open which means that engine did not received enough oil to the bearing and shims and therefore it was like it had more friction on them that resulted in the engine to turn slower and make a hell of a metal noise. luckly the engine did not break but i think it went close. This was for my bike but that does not mean that yours has the same problem. Just an advice it could be something to look into it. For the rest the bike is perfect and i have never had any other issue with it i think it is worth the money i paid for it and the quality of the components is very good i hope this coul be helpful for you
all the best
Got any pictures of the install process?
 

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The noise I get is definitely from either a valve chain or adjuster/tensioner. I have less than 200 miles on my CBR and I find that when I hold the revs at the start of the noisy engine, it definitely sounds like a cam chain loose and rattling on the engine case. All this happens between 4000 and 5500 rpm. Sounds like the engine is just noisy from what I have read on here so I am not too concerned but I will mention it to the dealer when I get them to service and adjust the valves. If it doesn't improve I might be inclined to do some investigation myself.
 

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My PCX150 has the bb in a tin can rattle pretty much all of the time. It's not quite as heavy or loud as the CBR even if it is 100 times more frequent. Oh well. I really don't believe it is a longevity issue and the dealer still apparently have no tech bulletins on it so I can't worry about it.
 

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Hi just answering to your quest.
I am the owner of a brand new cbr 250r 2011 model but i bought it last january and so far the clock reads 6500 km almost. this bike from the start always sounded like a metall tin with some nail in it. It is the engine that rattles in mine and took me sometime to understand what was wrong with it. I took it back to the dealer where i bought it at first but the did not do much and said to me that it was normal.
I insisted to find the problem myself since i have a little mechanical knowledge and i had the feeling that the engine oil pressure was too low. Since this bike has not got an engine oil alarm light on the dash to be sure i was right i checked the engine myself.
I have removed the engine oil pump from the engine which is located on the right side of the engine just next to the clutch and removed and changed with a brand new an oil pressure relief valve wich is located behind the oil pump and attached to it (i paid 33 euros for it from the honda dealer) close the right cover of the engine and assembled it in reverse to start the engine again. Once everything was ready i started the engine and went for a test ride. Result is the it is now a new bike, the rattle is gone no more little vibrations on the handle bars quite engine and top speed of 160 km per hour. Before this little service it only reached a top speed of 150 kmh. This little valve that i changed it was jammed open which means that engine did not received enough oil to the bearing and shims and therefore it was like it had more friction on them that resulted in the engine to turn slower and make a hell of a metal noise. luckly the engine did not break but i think it went close. This was for my bike but that does not mean that yours has the same problem. Just an advice it could be something to look into it. For the rest the bike is perfect and i have never had any other issue with it i think it is worth the money i paid for it and the quality of the components is very good i hope this coul be helpful for you
all the best
Anything to report after 2 months of changing the valve?
 

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I've got a metal on metal sound coming from the front of the engine. 2011 Honda cbr250 with 8km on the clock, does it with the clutch in and out but only when I hit the throttle. Even the tiniest touch to the throttle makes this sound. For a showroom bike its quite worrysome, I checked the oil and the fuel doesn't seem stale but that will be replaced. Going to a mechanic next week to get a diagnosis. My ninja doesn't do this....
,
 

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I've got a metal on metal sound coming from the front of the engine. 2011 Honda cbr250 with 8km on the clock, does it with the clutch in and out but only when I hit the throttle. Even the tiniest touch to the throttle makes this sound. For a showroom bike its quite worrysome, I checked the oil and the fuel doesn't seem stale but that will be replaced. Going to a mechanic next week to get a diagnosis. My ninja doesn't do this....
,
Does it have coolant in it? That masks a lot of noise but is noisy if it is empty or low.
 

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I've got the 5-6k rpm rattle also. Had it from day 1 (which was only two weeks ago). New rider, first bike, so I'm kinda' bummed. Gonna have the service techs take a look at it. Will report back what's found.
 

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I had the rattle too around 5500RPM. I put some little bits of foam between the washers and brackets of the pegs and pillion pegs, seems to have gone I think. Haven't noticed it as much.
 
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