Coventry Bees' place in the 2011 Elite League season is in doubt, BBC Coventry and Warwickshire understands.
New regulations relating to rider's averages, put into place at the Annual General Meeting of speedway's governing body, prompted The Bees to walk out.
It is thought Coventry had agreed a deal to sign Kenny Larsson from Newcastle and his average would be notably higher under the new rules.
The Bees are currently the reigning Elite League champions.
The Bees were joined in their walk-out by Peterborough Panthers.
It is believed the new regulations would alter the way that riders from the Premier League had their averages altered, when stepping up to the Elite League.
At the moment the average is halved but the BSPA now wants the riders to retain 70% of their previous Premier League average.
A BSPA source said on Wednesday morning: "The BSPA are likely to issue a statement within the next 24 hours which will confirm that Coventry Bees will not defend their Elite League title next season."