The diodes allow the CD4017 to charge the capacitors at the base of a transistor but prevent the CD4017 from discharging the capacitor to turn off the transistor and LED.
Add a 10k resistor to ground at the 47k base resistor at the diodes.
Hey Thanks Audioguru I'll try that. I had really strange behavior with it and I
am not sure what it was. When idle it looked great but when I started rolling it would speed up, only light the first few LED's and repeat that.
Not sure if it was vibrations causing it or not. It really acted like it was a bad solder joint or something.