I have a 7 speed old Trek 1400 bonded Aluminum road bike. I currently have the 8 of 9 cogs specifically a 12-25 9 speed casette with the 14 left off (I can't leave off the 12 because it has teeth on the outside that mesh with the cassette lockring) so it is 12-13-15-17-19-21-23-25. I squeezed in a 130 wheel before but since it is a beater bike at this point I just keep the 126 wheel. Since you have a steel bike if you ever decide you want to get a modern 130 wheel take it to a bike shop and they will spread and allign the dropouts for you from 126mm.