Get a metronome. Practice single notes and then double those notes
and triple and quadruple the time over those metronome hits. Then
use the metronome strike as the upbeat and repeat. Then start
playing scales and arpeggios.
Try to think like a bass player rather than a melody instrument.
I listen to more rhythm players these days then melodic players. In
fact there are few melodic players on any instrumet that I find
particularily interesting. Tabla, djembe, bodran, doubek, riq are my
best friends of late. Aside from Mr Peloquin, Mr Ricci and Mr Brooks
if you're nasty! Even Rosco too...
Your best players on any instrument are great rhythm players.
Get your groove on!!