I have developed a high picthed whine, sounds like a turbo spooling up, not noticeable moving in neutral and reving engine. And not noticable stationary when reving, increases in pitch with revs and seems louder in higher gears as the engine loads up, assumption being that it’s the drive train, gearbox or output of drive sprocket. Does anyone remember any particular weaknesses of any bearings. I have not dropped the oil yet as practically new but am not relishing spliting the crankcase looking for a phantom bearing but it seems likely that’s my only option as a hard failure would be expensive? Any thoughts or knowledge greatly received. Nick.
The easiest and most obvious things to check are the chain adjustment and lubrication, front and rear drive sprockets, and rear wheel alignment. I hardly need add: check that there is not some loose component or protruding bolt touching the tyres, wheels, discs, or sprockets. Assuming those matters are OK, here is a question. Is the whine the same in all five gears, or only in certain gears? If a gearbox bearing is collapsing, you would expect first gear to whine most if it is a bearing on the clutch (right) side; but if a bearing on the output sprocket (left) side then second gear would be whining most. Moving on, if the clutch bearings are packing up, this could cause the primary drive gears to whine. You could take off the right side cover, and remove the clutch pressure plate, springs, and drive plates. Then you can check whether there is any play in the two ball races at the back of the clutch - you should not be able to feel any play at all. If none of the foregoing enables you to diagnose the problem, but you feel the whining is too serious to ignore, eventually you might be obliged to strip the whole engine to bits so that all the bearings can be checked directly. you would need a copy of the workshop manual to do that, plus some special tools. Good luck. Do let us know what you discover, if anything.
Thanks for the excellent response, the whine is not there coasting in neutral around thirty which would seem to exclude wheels, chain etc., It definitely follows throttle increasing as revs pick up. With the bike back in the garage on the stand, the noise seemed to be louder in second whist in gear, revving the engine and spinning the back wheel which could be the output sprocket bearing. I will look into the replacement of this first, I have the Ducati workshop manual and will see if this can be replaced with out a crank case split which I hope to avoid for the reasons stated. I recently replaced the clutch and no obvious anomalies where found, no guarantee I know but the output bearing would seem a good place to start will update the thread with findings as they materialize. Thanks. Nick.