You would want to be in the Red group.
Bikes that pass you on the straight won't hold you up in the corners, and, your corner speed won't be an issue. Your lines will be good and it won't be an issue for a faster bike to get by.
I ride towards the top end of Yellow and constantly have the issue of passing a litre bike out of a corner only to have them pass me back on the straight. Often these are riders who don't know the track (and take unpredictable lines) leaving me stuck behind them for a lap of more to make a safe pass. This doesn't happen in the Red group.
Occasionally I'll ride with the Red group and enjoy it much better; any bike that passes me, stays passed me.
Bikes that pass you on the straight won't hold you up in the corners, and, your corner speed won't be an issue. Your lines will be good and it won't be an issue for a faster bike to get by.
I ride towards the top end of Yellow and constantly have the issue of passing a litre bike out of a corner only to have them pass me back on the straight. Often these are riders who don't know the track (and take unpredictable lines) leaving me stuck behind them for a lap of more to make a safe pass. This doesn't happen in the Red group.
Occasionally I'll ride with the Red group and enjoy it much better; any bike that passes me, stays passed me.