Water is a byproduct of combustion and a bike ridden on short journeys only for a period of time will never reach a high enough temperature to vapourise the water and fully burn the petrol, the left over can make its way past the rings into the sump.To many short journeys can cause what you are describing and you mention a 3 mile journey.Change the oil and oil filter, then go for a 30 mile spin at reasonable speed.
10w/40 is 10w/40
Quote from: darrsi on 20 June 2013, 01:07:50 am10w/40 is 10w/40 Not true The are 3 basic types of 10/40 oil Mineral 10/40Semi Synthetic 10/40Synthetic 10/40Neither should be mixed with each other, whereas you may top up semi synthetic with fully synthetic and fully synthetic with semi synthetic, under no circumstances should mineral oil be mixed with fully synthetic of semi synthetic.As I said the specification should match before you decide to mix
Quote from: unfazed on 20 June 2013, 05:14:28 pmQuote from: darrsi on 20 June 2013, 01:07:50 am10w/40 is 10w/40 Not true The are 3 basic types of 10/40 oil Mineral 10/40Semi Synthetic 10/40Synthetic 10/40Neither should be mixed with each other, whereas you may top up semi synthetic with fully synthetic and fully synthetic with semi synthetic, under no circumstances should mineral oil be mixed with fully synthetic of semi synthetic.As I said the specification should match before you decide to mix10w/40 is 10w/40, sure, there is mineral based oil and synthetic ester based oil, but there's no ill symptoms of mixing them, and you'll find that even most "Semi-Synthetic" and "Fully Synthetic" oils are already diluted with upto 20% standard mineral oil anyway!There was an article by the Chief of R&D at Silkolene/Fuchs a few years ago which highlighted exactly this.