Leeroy,
On the track the rear bump steer dosent impact much (unless you run off the track) but on the road where there are lots of bumps its a feeling that the rear is moving about more than you would like.
For those that have a 300kw billy cart just jump up and down on the rear and watch the wheels change toe angle.
Apparently there is a guy in NZ with a CR that has worked it all out but I have no details. Mando may have designed his out too when he carried out major surgery to his CR to get the dished wheel look .
Understeer can be cured with more power to the rear wheels
Spoke to Michael at Pedders, he is going to do an initial run of 6 bars plus one for a pattern should there be any further interest.
Phil