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Hi All, i have been reading these forums for a while but never posted as luckily didnt have any reason.

However now i have noticed that when im in neutral and have the clutch relased out i can feel a rattle through the foot brake and frame. As soon as I pull clutch in, the engine is very smooth.

Is this normal or showing signs of failure? Also the bike sounds a bit strange on startup and sounds fine again when clutch pulled in, however this is very temperamental, maybe once in a month.

its a 2017 CB500f with 5500 miles on the clock. ive checked the clutch freeplay and thats all good, so wondering whether something inside is lose or not right?
 

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Hi All, i have been reading these forums for a while but never posted as luckily didnt have any reason.

However now i have noticed that when im in neutral and have the clutch relased out i can feel a rattle through the foot brake and frame. As soon as I pull clutch in, the engine is very smooth.

Is this normal or showing signs of failure? Also the bike sounds a bit strange on startup and sounds fine again when clutch pulled in, however this is very temperamental, maybe once in a month.

its a 2017 CB500f with 5500 miles on the clock. ive checked the clutch freeplay and thats all good, so wondering whether something inside is lose or not right?
I can only say my bike has no noises what so ever. But that doesn't help you. Have you had a check round of all bolts and fastenings. You could do with some experienced ears to listen to it Have you got a stethoscope, if not get a piece of hose pipe put it to your ear and go round the bike when it is rattling, that will give you a idea of where the noise is coming from.
 

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This is usually due to an uneven idle, as the engine is not ideling evenly (usually due to incorrectly synchronized carburetors or inlet throttle plates) the gears are constantly being accelerated slightly and then decelerated on every revolution of the crankshaft, this causes the gears to rattle and usually a small vibration can be felt. Once you pull the clutch level in, it adds a small additional loading to the transmission system and smooths things out, this is common on all motorcycle, not just your CBR500. It is not doing any harm, but if it bothers you, getting the carbs or inlet throttle valves balanced usually cures it.

Gary
 

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I'll second the sensation being normal.

The 500 has a 180-degree crankshaft meaning the two cylinders fire 180-degrees apart. This is followed by 360-degrees of crank rotation before another combustion event occurs. Something like "*__..." (where '' is a power stroke and each character represents 180-degrees of rotation of the crank.) This "uneven" firing results in subtle crank speed differences at uneven intervals throughout the cycle. Put this through the primary gears, the clutch and the straight-cut constant-mesh transmission and you're going get some noise as the parts rattle against one another within their normal mesh tolerance.

Even bikes with even firing intervals (e.g. flat-plane crank I4s) will still make a similar noise just maybe not to the same degree.

My Tuono V4 has a 65-degree bank angle and a 180-degree crank; cylinders 1 and 2 share a crankpin and 3 and 4 share the other. That thing has a crazy uneven firing interval. When it's idling in neutral with the clutch lever released it sounds like this is going on inside the engine case:


As long as the oil level is correct and of the right type and viscosity, the clutch isn't grabbing or slipping and the transmission is shifting up and down smoothly, I wouldn't worry about it.
 
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