OzVMX Forum

Clubroom => Tech Talk => Topic started by: lms6201 on May 28, 2009, 06:08:51 pm

Title: bearing / crank / case assembly , seal fitment (yamaha )
Post by: lms6201 on May 28, 2009, 06:08:51 pm

thanks to all helpful bits so far , i,ve done this assembly many times , but i,d like to see if there are better ways , , is it better to fit bearings to cases then fit the shaft ? the yams i,ve had to disasemble have mostly been for  tranny issues and when the bearing is tite on the crank and doesn,t need replacement i can,t see the point of going through the trauma of getting it off ,   how tite should they be ?  all the bultaco,s i,ve rebuilt , the bearing / shaft fit is a lot less tight  , also  yamaha seals go castelation,s in , as far as i can tell from diagrams ( i have found them in some of my machines the other way round ) any confirmation ? the heavier seal lip would be inside ? tia

Title: Re: bearing / crank / case assembly , seal fitment (yamaha )
Post by: holeshot buddy on May 28, 2009, 08:06:13 pm

seals go castelation inwards
i usually install bearings in the case first
never have problems ;)

Title: Re: bearing / crank / case assembly , seal fitment (yamaha )
Post by: gorby on May 28, 2009, 08:25:33 pm

cold bearings from the fridge into heatgun warmed cases,then cool crank into warmed bearings :)

Title: Re: bearing / crank / case assembly , seal fitment (yamaha )
Post by: holeshot buddy on May 28, 2009, 08:29:44 pm

WITH COLD BEER IN ONE HAND
AND WARM WOMAN IN THE OTHER ;D ;D

REMEMBER IMS MAKE SHAW TOUNGE IS POINTING RIGHT WAY :P

Title: Re: bearing / crank / case assembly , seal fitment (yamaha )
Post by: lms6201 on May 28, 2009, 09:50:26 pm

thanks for the seal confirmation , try and get this crank looked at tomorrow ,

Title: Re: bearing / crank / case assembly , seal fitment (yamaha )
Post by: vandy010 on May 29, 2009, 12:33:16 am

i usually fit the flywheel side bearing to the crank first, then drop that assembly into the left side case.
i fit the seals after the bearings are in.
to remove the bearing off the crankshaft, i take the crank assembly {with old bearing still mounted} down the the bike shop and have them remove it for me. i just find it easier that way.
i point my tongue to the left when working on the left side case and to the right for the right side case also and have never had a problem in doing so.
some other "motors" will require the tongue facing forward.......
but thats another story.....