Kinjane
New member
how could the CO settings affect the gearbox's roughness 
Fairly simply actually, the CO bypass outlet tube feeds directly into the bottom of the sump, and it's this same CO enhanced oil that's also used for the gearbox lubication. Unfortunately CO when pumped under pressure through a viscous fluidic medium such as engine oil can cavitate at certain pump speeds which happens to correlate in this instance to between 3-4K rpm. It's this excess CO that makes itself known in the form of tiny bubbles that can be seen quite clearly through the sight glass sitting on top of the oil whenever the engine has been run for a while
OR it could be that it only feels like a gearbox problem because the expansion section of the exhaust is bolted to the bottom of the engine directly underneath it.
The exhaust pulses from the lean mixture is resonating within the 'scrotum' as it's been aptly named, and this vibration is simply being felt elsewhere. Richening up the AirFuelRatio via the CO settings reduces this.
BUT it is also a very very very slight outside possibility that if the bike has been run for the last 5,000 miles on the factory recommended drive chain settings the gearbox ouput shaft bearing is now excessively worn and might be suffering harmonic vibration whilst rotating between the quoted 3-4000 rpm. If so then in all likelyhood the ball race cage will eventually break apart releasing the round shiny balls into the engine which will soon end up looking like dented frozen peas and probably scrapping the engine in the process. I doubt that this is the case.
This is why I suggested a simple easy little test be conducted by the OP. Especially as the EU emissions generated lean mixture problem has a no-cost cure which can be carried out in less than two minutes.
But in reply to the OP's question...Yes, in all likelyhood it's a characteristic of the bike - just not one you have to put up with.
Fairly simply actually, the CO bypass outlet tube feeds directly into the bottom of the sump, and it's this same CO enhanced oil that's also used for the gearbox lubication. Unfortunately CO when pumped under pressure through a viscous fluidic medium such as engine oil can cavitate at certain pump speeds which happens to correlate in this instance to between 3-4K rpm. It's this excess CO that makes itself known in the form of tiny bubbles that can be seen quite clearly through the sight glass sitting on top of the oil whenever the engine has been run for a while
OR it could be that it only feels like a gearbox problem because the expansion section of the exhaust is bolted to the bottom of the engine directly underneath it.
The exhaust pulses from the lean mixture is resonating within the 'scrotum' as it's been aptly named, and this vibration is simply being felt elsewhere. Richening up the AirFuelRatio via the CO settings reduces this.
BUT it is also a very very very slight outside possibility that if the bike has been run for the last 5,000 miles on the factory recommended drive chain settings the gearbox ouput shaft bearing is now excessively worn and might be suffering harmonic vibration whilst rotating between the quoted 3-4000 rpm. If so then in all likelyhood the ball race cage will eventually break apart releasing the round shiny balls into the engine which will soon end up looking like dented frozen peas and probably scrapping the engine in the process. I doubt that this is the case.
This is why I suggested a simple easy little test be conducted by the OP. Especially as the EU emissions generated lean mixture problem has a no-cost cure which can be carried out in less than two minutes.
But in reply to the OP's question...Yes, in all likelyhood it's a characteristic of the bike - just not one you have to put up with.
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