8  Boast in Siouan language (4)

 9  Before start of engagement, performing quintette's standards for good online behaviour (10)

10 Rotten Mongolian tent gives worry (6)

11 Norwegian composer consuming French alcohol, generating distress (8)

12 Unlimited fast gauges for officers in charge of weights and measures (8)

14 Beam about score in Hampden Park; uncommon thing (6)

16 Tolerate ill-mannered fellow (4)

17 Torment essentially digging small trench (5)

18 Hear about speed (4)

19 Good old feast producing bellyache (6)

21 Highly attractive hospital department killing in Hollywood (8)

23 Vivid red colour of part of scratchcard in a lottery (8)

26 Jewish teacher with time for insignificant person (6)

27 Instrument of sweetheart finally able to court in a sentimental way (10)

28 Half of team regularly fall for dark greenish-blue colour (4)

 2  With greater number of small offshoots; more like a sixties fashion model? (8)

 3  Section of vent re-engineered for means of access (6)

 4  Pistols casually taken up for better in the market (4)

 5  Hoard of young nobleman involving one hand followed by the other (8)

 6  Work very hard at beard (6)

 7  Shock when small lumps of coal turn up (4)

13 Pines about verbal attack (5)

15 Twisted carnality with touch of nastiness characteristic of 22 (10)

17 Nondescript nature of white horse, say, on headland (8)

18 Old weapons roughly cut backsides (8)

20 Excessively turbulent when Democrat supplants Republican (6)

22 Cruel dictator's hollow thundery bombast (6)

24 Partly open a wide-mouthed vessel (4)

25 Can name simple-minded person (4)