Needle bearing in vector Motor ?

[sportster64]

I was looking at the microfich of the 2005 vector motor. I see that the shaft that sits in front of the crankshaft on the crankshaft piston microfiche is assembled with a needle bearing. Dealer told my that is a balance shaft. Is anyone concerned that yamaha put a needle bearing in there ? What about durability ?

 

[rxrider]

No need to worry, the needle bearings used is very tough. The 2strokes had needle bearings between connection rod and piston wrist pin, some cars have them in their transmission/gearbox.