Plug, Straight Screw(2nl) Xs850l 1980 (a) Usa

Drive shaft assemblies (especially Japanese engineered types) are both reliable and durable over the longer term, and of course avoid the need for constant lubrication and adjustment that chain drives require.
But, eventually, you will experience drive line shunt when closing and opening the throttle, play between the shims will become more pronounced and possibly develop lubrication leaks - but rarely a complete failure.
However, "a stitch in time saves nine", an old English saying, stating that early preventive maintenance could spare a whole heap of expensive trouble down the line.
Striping and inspecting the shaft drive assembly and the ancillary components would be a sensible winter task. Some of the parts you may require, apart from this component, are listed below.

4H74612500
4NK4610100
9011610593
9011610361
9011608427
9581710050
1FK4615300
9321060426
9330630533
9310138098
4H74612301
90201166R5
9017916661
2H74610200
1J717537Y030
1J717537Y040
1J717537Y015
1J717537Y050
9310130084
9331601403
9331143729
22U4611800
22U461180012
22U461180014
22U461180016
22U461180018
22U461180020
1FK4615201
9321154698
9531708600
9533708600
9310270167
56W1759000
9034014135
9290708700
1J746117Y030
1J746117Y025
1J746117Y040
1J746117Y045
1J746117Y050
1FK4615400
1FK4615600
1FK461570015
1FK461570020
4NK4617200
4XY4617200
9310823007
9310843013
90201231A2
9341022039
4X74618000
9331121044
9339999926
9050116491
9344020088

Preventive maintenance can help avoid major problems down the line.

Add as many items as you wish to the same shopping cart, new fasteners and seals for example, and still only pay the same single fixed price shipping cost.

This component may have other applications within the Yamaha model range.