I'm rebuild the bottom end of a 250r. I took the crank and put it in the freezer to get it cold and heated up the bearing. Didn't work. I was told there is some tool out there that can help me.[img]i/expressions/face-icon-small-mad.gif[/img]

 

Heres a link to a online service manual it should show you how.
Service Manual

 

How long did you cool and heat the crank and bearing, respectively? When I do that, I leave the crank in the deep freeze for at least 24 hours, and I heat the bearing for about 30 minutes with a heat gun on low. That way, all of the material is very near the same temp all the way through. If you don't wait long enough, only the surface of the materials will change in temp, which does nothing. You want the core material to shrink or expand. Also, have the bearing ready to go as soon as the crank is taken out. Don't keep the crank out for very long at all. Metal absorbs heat much faster than it rejects it.