BusyLittleShop said:The risk of increased wear is thouroughly documented in various books and manuals on the subject (hence the ones I previously used as references)
There is no shortage of book and manuals on the risk of increase wear
but there is shortage of first hand knowledge that someone worn out
their motorcycle engine running their choice of oil... in the real
world the vast majority grow tired of their bike and sell before they
wear it out...
If we analyze the actual Cts numbers between Motul 300V 10w40 and
Mobil 1 0w30 at operating temp of 212F we note the difference in
viscosity is only 2.6 Cts... thats not 2.6 Cts thinner or thicker...
the measurement is 2.6 Cts in flow... although 2.6 Cts more flow
increases the amount of HP at the rear wheel... 2.6 more flow doesn't
risk increase wear... our modern engines protected by modern oils don't
operate with in a narrow 2.6 Cts range of risk...
Motul 300V 10w40 @ 212ºF 13.2 Cts
Mobil 1...........0w30 @ 212ºF 10.6 Cts
Difference..............................2.6 Cts
.
BusyLittleShop said:The risk of increased wear is thouroughly documented in various books and manuals on the subject (hence the ones I previously used as references)
There is no shortage of book and manuals on the risk of increase wear
but there is shortage of first hand knowledge that someone worn out
their motorcycle engine running their choice of oil... in the real
world the vast majority grow tired of their bike and sell before they
wear it out...
If we analyze the actual Cts numbers between Motul 300V 10w40 and
Mobil 1 0w30 at operating temp of 212F we note the difference in
viscosity is only 2.6 Cts... thats not 2.6 Cts thinner or thicker...
the measurement is 2.6 Cts in flow... although 2.6 Cts more flow
increases the amount of HP at the rear wheel... 2.6 more flow doesn't
risk increase wear... our modern engines protected by modern oils don't
operate with in a narrow 2.6 Cts range of risk...
Motul 300V 10w40 @ 212ºF 13.2 Cts
Mobil 1...........0w30 @ 212ºF 10.6 Cts
Difference..............................2.6 Cts
.
I don't mean to sound rude, so please don't take it in that frame of mind, but what you're saying is that you agree there is no shortage of books or manuals (from respected motorcycle manufacturers and tribologists that are engineers and chemists in their respected fields) that do show the increased risk of wear with thinner viscosity oils, but because you haven't witnessed increased wear or mechanical issues you dismiss factual information?
I find it difficult to beleieve that the big four Japanese manufacturers felt it was necissary to design an entire oil class and specification for no reason at all, especially when they state, "can cause clutch slippage and gear pitting wear in motorcycle transmissions...leading to poor gear durability with these problems TESTED AND OBSERVED IN THE FIELD". If you're looking for real world testimony from motorcycle manufacturers that warranty, repair, and inspect motorcycles, I don't know what else you could ask for. Just because motorcycle oil failures aren't a regularly discussed topic, it doesn't mean they don't occur, like how Eric Buell's latest EBR motorcycles had experienced engine failure from oil with a lack of oil film strength and lower ZDDP concentrations.
Again, while 10W30 is acceptable when within the ambient temperatures set by the manufacturer that is one thing, but you haven't commented on how my coworker was able to maintain the same consistent lap times when going from 10W40 to 20W50 if he was down a further 1-2 hp, how would that be possible? Also the fact that once the oil shears via the VII's and fuel dilution can also take place, how well would a 0W20 protect your engine and gearbox?
Again, I dont mean to sound short, and I understand your position and the differences in the centistokes measurement, and that viscous drag can reduce power by 1-2 hp, but I would rather lose an unnoticeable 1-2 hp and follow the manufacturers and engineers guidelines for the longevity of the bike, especially in the harsh conditions racing presents.
BusyLittleShop said:The risk of increased wear is thouroughly documented in various books and manuals on the subject (hence the ones I previously used as references)
There is no shortage of book and manuals on the risk of increase wear
but there is shortage of first hand knowledge that someone worn out
their motorcycle engine running their choice of oil... in the real
world the vast majority grow tired of their bike and sell before they
wear it out...
If we analyze the actual Cts numbers between Motul 300V 10w40 and
Mobil 1 0w30 at operating temp of 212F we note the difference in
viscosity is only 2.6 Cts... thats not 2.6 Cts thinner or thicker...
the measurement is 2.6 Cts in flow... although 2.6 Cts more flow
increases the amount of HP at the rear wheel... 2.6 more flow doesn't
risk increase wear... our modern engines protected by modern oils don't
operate with in a narrow 2.6 Cts range of risk...
Motul 300V 10w40 @ 212ºF 13.2 Cts
Mobil 1...........0w30 @ 212ºF 10.6 Cts
Difference..............................2.6 Cts
.
I don't mean to sound rude, so please don't take it in that frame of mind, but what you're saying is that you agree there is no shortage of books or manuals (from respected motorcycle manufacturers and tribologists that are engineers and chemists in their respected fields) that do show the increased risk of wear with thinner viscosity oils, but because you haven't witnessed increased wear or mechanical issues you dismiss factual information?
I find it difficult to beleieve that the big four Japanese manufacturers felt it was necissary to design an entire oil class and specification for no reason at all, especially when they state, "can cause clutch slippage and gear pitting wear in motorcycle transmissions...leading to poor gear durability with these problems TESTED AND OBSERVED IN THE FIELD". If you're looking for real world testimony from motorcycle manufacturers that warranty, repair, and inspect motorcycles, I don't know what else you could ask for. Just because motorcycle oil failures aren't a regularly discussed topic, it doesn't mean they don't occur, like how Eric Buell's latest EBR motorcycles had experienced engine failure from oil with a lack of oil film strength and lower ZDDP concentrations.
Again, while 10W30 is acceptable when within the ambient temperatures set by the manufacturer that is one thing, but you haven't commented on how my coworker was able to maintain the same consistent lap times when going from 10W40 to 20W50 if he was down a further 1-2 hp, how would that be possible? Also the fact that once the oil shears via the VII's and fuel dilution can also take place, how well would a 0W20 protect your engine and gearbox?
Again, I dont mean to sound short, and I understand your position and the differences in the centistokes measurement, and that viscous drag can reduce power by 1-2 hp, but I would rather lose an unnoticeable 1-2 hp and follow the manufacturers and engineers guidelines for the longevity of the bike, especially in the harsh conditions racing presents.
Quite right.
There is no track in the world, where in real life qualifying conditions one could ever possibly measure 1-2 hp(actual) difference between two motorcycles, that are for all intents and purposes identical.
Even when ridden by the same rider and set up exactly the same way to the rider's requirements for maximum performance.
A figure of 4-5 hp or more is realistic to be able to measure a difference in qualifying track times, but 1-2 hp is dreaming.
I'm not even convinced that one would get 4-5 hp difference between running a 10w-30 grade oil and a 15w-50 grade oil in the same assembly that's producing 125+ hp anyway.
A 5w/10w-40 grade oil has been proven to be adequate in virtually all applications like the OP's. Especially given the requirements of the transmission as has been mentioned by yourself.
I personally would rather follow the manufacturers/engine builder's recommendations and be happy with what I'm doing.
For example, DUCATI even spec/recommend a 15w-50 grade full synthetic oil for their heaviest hitting street legal race bikes that develop in the order of 195+ hp.
Further.
Oil pressure and or flow are not the be all and end all(holy grail) of the full lubrication requirements of any shared sump assembly.
The engineers that designed the machine know the best out of anybody in the world.
I suppose one could easily run a 0w-20 grade oil and get away with it.
For a little while at least.