The only thing that happens in 15 mins is the engine warms up and the oil thins as it's pumped around the engine. One possibility is that you have dirty/ contaminated oil. I'd suggest changing the oil if it hasn't been changed recently first....and when you do so look for any metal shards in the oil. You'll see some metal dust in the oil drain plug filter (which is normal) but if it looks to be unusually dirty then plate wear could be going on (and that's not helped by dirty oil). There are lots of bits in a clutch so anything could be going on. Check the oil is the right type and that it's topped up to the recommended level. If the oil level is low before you change it then check there are no oil leaks from the engine gaskets.
On this model bike you have a wet six plate hydraulic clutch and they are usually very good. It might be that something else is going on there - plate wear/ slip or drag in which case a dismantle and overhual will be required at some point. Or even a hydraulic fluid leak which would float to the top of oil when the engine is cold and make plate lubrication difficult. How does the clutch run once you can get it to work? Is it smooth as it should be? Or does it clonk into gear? Is the lever spongy (need to bleed hydraulic fluid possibly) ?
Change the oil first and if the problem continues then come back with a description of the 'feel' of the clutch as you step it into gear and it engages........
Angela.
February 2008
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