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Ok so every week I see a new thread or an old thread pop back up on this " engine rattle". These threads need to go away. My bike did it from day 1 and now has almost 6000 miles on it with no issue what so ever. I have had the top end off my bike and everything seemed perfect, piston to cylinder clearance, valve clearances, rocker clearance. This is what I have come to figure out. Atleast with me it's betweet 5-6000 I can hear it and if I open or close the throttle the slightest amount to where the RPM doesnt even change it go's away. To me it's vacuume related. You'r engine is not going to explode like a grenade. If you take the PCV valve off you'r car/ truck and shake it, that is exactly what this "rattle" sounds like. If you are that worried about it bring it to the dealer don't make another thread on it. Like I said it's a single cylinder bike, it vibrates. It IS NOT GOING TO CAUSE ENGINE DAMAGE! I'm not saying I know for a fact this is what's causing this sound but i'm pretty confident that it's something related to the emissions or evap system. Just RIDE IT!

Sorry had to vent a little.
 

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BAZINGA, Deanohh! :D ZOMG BBs IN A CAN OMG OMG OMG!

Every "beginner bike" forum is chock full of "rattle" threads. and "it sounds like my engine is going to pop if i rev it over 3500 rpm" threads too...

Freaking ride the thing. It's fine. You'll get used to what it sounds like to sit on top of an engine after a while.

And like others said, if you think it's a problem, take it to honda and pay them money to tell you it's still fine. Starting an "OMG WE NEED TO MAKE HONDA FIX THIS!" thread on a forum that is not run by honda, or starting a FB group about it, or posting tweets to #OMGImAn00bAndDunnoWTF is not going to fix your non-issue.

There, I said it. *sigh*

Thanks BBR, I needed that. :D
 

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*heavy sigh*:(:(:(:(:(
 

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Motorcycle dealers should be required to test all perspective buyers for common sense. Those who fail, are sent packing... to the bicycle store down the street. They can still have a two wheeler, just not one which burns gasoline...
 

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My bicycle makes strange noises when I shift gears.

This is obviously a safety hazard, and rather than investigate it further or discuss it with the bike shop, I think I'll join a bicycling forum and cry.
 

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I completely agree with BBR, I wish they were smart enough in my country to understand the nature of this sound. They made such a big deal of it and gave the CBR a bad name. Now the resale price is going down thanks to those morons. For god's sake!!!! It's a single cylinder engine!!!!! common !!! I'm sure it's going to be known as one of the best motorcycles of this decade.
 

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engine rattle possible fix

I have been riding since the mid 60's and just recently bought a cbr250r. It has rattled since day one at 5,500 to 7,000 rpm but it ran very strong.
I waited until after my 600 mile service (which went well and everything was fine other than 2 valve shims had to be replaced). The rattle was still there.
I was curious about the pair valve which is located on the valve cover. I removed the reed valve and the port plate below the reed valve. The port plate was totally loose in there. It is a very inexpensive part, stamped steel plate with holes to direct air to the pair valve. I removed the plate, put everything back together and disabled the pair valve by plugging the air line going in and capping the fitting going out. THE RATTLE IS GONE!
It instantly went from sounding like the engine was going to self destruct to a sweet sounding machine.
 

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Call me crazy.... But I just thought motorcycles rattled/vibrated.... After all you basically have an engine between your legs. Ha!


Sent from my iPhone using MO Free
 

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I have been riding since the mid 60's and just recently bought a cbr250r. It has rattled since day one at 5,500 to 7,000 rpm but it ran very strong.
I waited until after my 600 mile service (which went well and everything was fine other than 2 valve shims had to be replaced). The rattle was still there.
I was curious about the pair valve which is located on the valve cover. I removed the reed valve and the port plate below the reed valve. The port plate was totally loose in there. It is a very inexpensive part, stamped steel plate with holes to direct air to the pair valve. I removed the plate, put everything back together and disabled the pair valve by plugging the air line going in and capping the fitting going out. THE RATTLE IS GONE!
It instantly went from sounding like the engine was going to self destruct to a sweet sounding machine.
Is this a long term solution,would there be any adverse outcomes to doing this? I'm not too familiar with internals.
 

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I think you have a point...the little CBR is such a cool bike it's easy to forget it didn't come with a $10,000 price tag...As for myself, I'm gonna nitpick less, enjoy more...
 

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To be honest, I'd be much more concerned if my bike stopped making noise.

Sent from my not so smart phone using any means necessary
 

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Is it screaming?

Ride it like you stole it!

Is it not screaming?

Start it.

Will it not start?

Put fuel in it.

Is it screaming now?

Yes.

RIDE.
 

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The one thing that bothers me is that theres been no responce from Honda. The sound is annoying to me. Never heard anything like it from any other bike ive ever had.
 

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The one thing that bothers me is that theres been no responce from Honda. The sound is annoying to me. Never heard anything like it from any other bike ive ever had.
I know Tom. I feel ya.
 
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