We've taken the motors and put them side by side on a table. We have taken them apart before like I've said and might have tampered with the grease and whatnot. We know it's not electrical because when spinning the output shaft coming out of the clutch, one motor is more stiff than the other and they make different sounds (in terms of pitch) when spun. So all we need is for our motor expert to show up a meeting. Yeah...

Thanks for the ideas.

In programming, if you want to go straight, drive the slower motor at full speed (254) and drive the faster motor at some speed less than 254, determined by testing.

Have you also checked to make sure the little plastic ring on the transmission is in the same location for both? That is what switches the gears on the drill motors.

Shopping Cart Stability
 

jpsaul7usa,

You say your robot has two motor driven wheels and two casters. If you drive with the casters in front, like a shopping cart, such a robot tends to be inherently directionally stable. If you drive with the casters in the rear, the robot is INHERENTLY UNSTABLE and may quickly spin out, no matter what the driver does.

I leave it to you to discover the physics. If this is the problem, the solution is DRIVE "BACKWARDS." We discovered this with our first year's robot, after the competition. We coulda been a contender..............

Does this apply? Good luck.

Dodd