1982 vision crankshaft end play spec

[turbovision]

Hi ;
I am hoping someone can shed some light on this question.I need to know the spec for crankshaft side to side play on my 1982 vision that I have been restoring for many years,The shop manual does not give a listing for this,shy of stating the crankshaft thrust face to thrust face should measure 104mm which mine does exactly,with the crankshaft installed and crankcases tightened up I measure 21 thousandths side to side play using a dial indicator,this seems too much to me,the thrust faces which are intergral with the crankcase halfs show no signs of abnormal wear at all.Perhaps nothing is wrong,If someone could give me a idea from their experence working on their bike.

thanks to all in advance
Jim Ruska

[fret not]

I don't know the answer.  What comes to mind is that there is not much to cause any side thrust.  No helical gears.  I think you should be OK.  The engine needs a bit of expansion room when it warms up.  Maybe I should check some of my spare motors. 8)

[Rikugun]

If the crank width is right and there is no apparent damage to the thrust surfaces on the crankcase halves I'd think you are probably ok. There is no thrust on the crank so I don't know why there would be excessive wear. Is your measuring setup solid and accurate? Does the installation of the primary gear take any of the clearance away through spacers/thrust washers?

[turbovision]

Hi
Thanks for your reply,I was very carefull while measuring the end play.There are no other parts or gears including the primary drive on either side of the crankshaft that could possibly affect the crankshaft end play.
Thanks Again
Jim

[motoracer8]

 That is quite alot of end play for a small engine, a V8 Chevy has less.
  Since the thrust surface is machined onto the cases there is no easy way to adjust it.  A 70's BMW twin with a simular crankshaft setup, plain bearings, has a .004 to .006 end play.  As stated in other posts there is little to no side thrust on the crank with straight cut primary drive gears. The rods are suppose to have .013 to .017 side play on the crankpin, thats probbably to put up with the floating crankshaft.

  Ken G.