With just over three weeks to go until the first practice session, many TT sidecar crews have plenty of work to do to ensure their machines make the start line.
A large number of the field need to replace the passenger platform, as many of the outfits currently do not meet the requirements set out in the supplementary regulations.
Lap record holder Nick Crowe has criticised the timing of the announcement and fears many will not make the deadline.
Current world champion Tim Reeves (pictured) is making his debut around the Mountain Circuit this year.
He says he has only been made aware of the serious consequences of the situation since coming to the Island this week:
Boxing: Jamie Devine's title fight called off
Athletics: Top-five for Cain at Swansea Half Marathon
Jamie Cringle 'a couple of steps closer in the right direction' after TT crash
Football: Castletown and 'Youthie' into Paul Henry Gold Cup final
Jade Burden 'so fired up' for rearranged title fight