I have a ’99 SX 600 triple that has about 8,800 miles on it. Right now I am going through the entire sled fixing or replacing everything that is worn out (basically doing a major complete rebuild). Last night I took the reed cages out to replace the reeds so I took a look at the crank and piston skirts. The skirts all look like they are still brand new. Not a mark on them or any wear. However, the crank bosses on the mag-side of each connecting rod bearing have some pretty heavy “blueing” indicating that they have gotten pretty hot at one time. Is this blueing from the mfg process of the crank or is it from an overheating condition in the engine? If it were from an overheating condition I would like that the crank boss on the clutch side of each bearing would show the same blueing but they do not.
I was using the clutch to slowly spin the engine over to view everything and noticed that there is a little backlash in all of the crank/connecting rod bearings - is this normal? If so, how much is normal and how much is out-of-spec?
Also, the clutch seemed to have a little bit of backlash in it as well. I grabbed the clutch by the spider towers to rotate the engine and noticed that that half of the clutch rotated a slight bit before the stationary sheeve began to rotate. Is this normal? I had the local Yamaha shop take the spider out of the clutch to replace all the bushings about 800 miles ago and I am wondering if they didn’t get it tight when they put it back on.
Last question – does the reed cage notch really improve the performance of the engine that much or is it not worth doing? I have already spread the reed stops out 1mm which gave me maybe a little bit better mid range and top end performance but, if I am not going to get much out of the cage notching then I am not even going to mess around with doing it.
Thanks for any advice you can give.
Mills
I was using the clutch to slowly spin the engine over to view everything and noticed that there is a little backlash in all of the crank/connecting rod bearings - is this normal? If so, how much is normal and how much is out-of-spec?
Also, the clutch seemed to have a little bit of backlash in it as well. I grabbed the clutch by the spider towers to rotate the engine and noticed that that half of the clutch rotated a slight bit before the stationary sheeve began to rotate. Is this normal? I had the local Yamaha shop take the spider out of the clutch to replace all the bushings about 800 miles ago and I am wondering if they didn’t get it tight when they put it back on.
Last question – does the reed cage notch really improve the performance of the engine that much or is it not worth doing? I have already spread the reed stops out 1mm which gave me maybe a little bit better mid range and top end performance but, if I am not going to get much out of the cage notching then I am not even going to mess around with doing it.
Thanks for any advice you can give.
Mills