Man, I haven't updated this thread in forever.

The RR-01 (now called the XV-01 R) is now 4WD, with a ball diff in the rear and a spool in the front. The rear springs were stiffened from blue-stripe to white-stripe (the hardest TC springs Tamiya offers), and the carbon-fiber shock towers were "downgraded" to carbon-reinforced-plastic because they twist less. The Vaterra tires wore down too fast, and the Vaterra wheels cracked all around the rim, so I switched to HPI wheels and V-Groove Pro Compound tires.



After a couple gearing changes, it can now hit 45mph on a slight incline, and just today I finally motivated myself to finish a second body for it so I can save the first one for display purposes.









This is now my fastest car, slightly edging-out my RS4 rally car, and it handles marvelously. The gyro almost never has to do any work, as determined by shutting off the gyro and driving it around a bit. It handled almost exactly the same, but considering how fast this car can get into trouble, I'd rather have the gyro there to compensate for sticks and stones and damp spots on the pavement.