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  The motor is very compact with tiny sand cast magnesium crankcases.  It does not hold much gearbox oil at all.  It has carbon fiber motor mounts in the front and an aluminum cradle in the rear.  The swingarm actually passes through the rear engine cradle.  The motor mount bolts are titanium and the outer case screws are aluminum.  The porting arrangement favors mid range power as the transfer ports are huge. (see cylinder in "works parts") The reed cage is very large and is fed from a 38mm mikuni (stamped OW40) made just for this bike. Different pipes for different powerbands were available.  The kickstarter is titanium.

             

             

   A very small ignition (stamped OW40) uses a map curve just for this bike, and has a very small rotor.  The revs build up instantly.  This is all connected to a very small black box that is mounted in a fabricated aluminum bracket just ahead of the ignition coil.  Notice how close the countershaft sprocket is to the chain buffer.  Also notice the access hole in the frame to get at the upper motor mount bolt.                                

                    

  The rear hub is a very small sand cast magnesium unit that looks like it belongs on a 125.  It is laced to a Sun rim with Buchanan stainless heavy gauge spokes.  Bob preferred this over the larger ones used by the rest of the team.  The chain adjusters are machined from aluminum with brown anodized inserts that hold the chain adjusters in place when the axle is removed.  The ring that you see bolted to the hub is made from stamped steel.  It's purpose is to keep a derailed chain from getting tangled.  Very Clever.  In the lower photo, notice the custom wing nut extended far enough back for easy brake adjustments.  The rear torque arm is made of chrome moly and attached at both ends with heim joints for smooth performance.  The entire rear wheel assembly is very light.

                    

                    

   Anyone that had a Yamaha YZ in the late 1970's wanted a swingarm like this.  The shock mount was much lower than stock.  And the long sleek looks really stood out.  It is a work of art.  Check out the welds in the lower photo.  There were several lengths that the riders had a choice from.  This was the longest and Bob used this for the whole season.  The bike tracked very well with this set up.

                    

                                                          

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