Lets look at it another way who is still racing 125/250/400,s let me see,
Ok the following is a list of possibles.
1. Mark Parrett Honda CBR 400
2. Dave Madsen-Mygdal Honda RVF 400
3. John Burrows Honda CBR 400
4. Paul Dobbs Yamaha FZR 400
5. Steve Linsdell Yamaha FZR 400
6. Kevin Ago Murphy Honda CBR 400
7. Paul Corrin Yamaha FZR 400
8. Roy Richardson Honda RVF 400
9. Johnny Barton Yamaha FZR 400.
10. Darren Slous Yamaha FZR 400.
11. Robert J Price Yamaha FZR 400.
12. Robert A Price Honda VFR 400.
13. Mike Hose Kawasaki ZXR 400.
14. Manfred Vogal Kawasaki ZXR 400.
15. Tony Moss Honda CBR 400.
16. Henry Bell Yamaha FZR 400.
17. Richard Bairstow Honda CBR 400.
18. Wade Boyde Honda RVF 400.
19. Patric Martin Honda RVF 400.
20. Anita Buxton Kawasaki ZXR 400.
21. Heinz Chittka Honda CBR 400.
22. John Crellin Honda RVF 400.
23. Peter Magee Yamaha FZR 400.
The following top runners in the TT Big Bike classes who have rode 400 in the past 3 to 4 years who might be up for it again.

24. John MacGuinness Honda RVF 400 RLR.
25. Martin Finnegan Honda RVF 400.
26. Jim Hodson Yamaha FZR 400.
27. Jason Griffiths Yamaha FZR 400.
28. Ian Armstrong Kawasaki ZXR 400.
Then you have possible entrys from riders on Suzuki SV 650,s should the class be opened up to let them in.
Then of course you have the Dunlop Clan who would more than likley ride either 125,s or 250,s and their are a few riders like Bruce Anstey who i think would love to have a go on a 250 GP Bike again the list is endless if you look into it in debth and ask them riders them selves not everybody logs on to TT website .com you could Run the 125,s, 400,s and 650 twins in one class and the 250,s in the race as a seprate class like the old days 2 races in one these are my own thoughts i think its quite possible if it was put out to the riders and see what responce we get entry wise.....