Mar-Train Racing has apologised after supplying Michael Dunlop with the "illegal" engine which saw him lose his Supersport podium position.
The Ballamoney man placed second in yesterday's race but was later disqualified after a post-race inspection found a 'technical infringement' with his machine.
The Yamaha R6 engine - which was a spare - was found to have an illegal set of coated cam buckets; a component which had been legal two years ago when it was originally built.
Mar-Train has blamed an 'oversight' in personnel in the team and change in engine builder for the 'obvious irregularity' being missed.
Speaking before he was disqualified Dunlop admitted it had been a struggle to get the bike ready:
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