View Full Version : OS Hyper 50 - Tips and Troubleshooting Gudie
DebianDog
02-09-2006, 11:09 AM
Nice PDF write-up from John Beech (http://www.audacitymodels.com/whitepapers/OS_Max_50SX-H-screen.pdf)
I found that to b4e very interesting. Especially the part about the mufflers.
RC-Bearings
02-10-2006, 10:12 AM
His bearing installation method leaves a little to be desired, though. Any slight misalignment of the rear bearing during installation will cause it to bind and you may have to damage it or the crankcase to get it back out.
A better way to install the bearing is to freeze the crankshaft, place the bearing on the crank, freeze the bearing/crank assy and then install it into the heated crankcase. This assures proper alignment of the bearing during installation.
I wll ALWAYS caution against hitting a bearing with anything if you plan to use it again. One slip and you can put small dents in the races that will accelerate wear.
DebianDog
02-10-2006, 10:23 AM
Thanks for the tip, Paul.
I always get the crankcase hot enough to let everything slide easily into place. When the heat expansion ratio of aluminum is so much higher than steel, and considering that it carries heat much faster, I have never needed to freeze anything. 400º in the oven (speed bake if you got it) and everything will slide together without the need of any rough treatment, and you don't have to wait for the steel to cool down.
RC-Bearings
02-10-2006, 11:50 AM
Debian,
Be very careful heating metals that hot, especially bearings. They are heat treated to be dimensionally stable only to about 300 degrees F. While it doesn't change the hardness to heat them above that, they can change dimensionally whic would cause them to wear faster. :D