Handling..ermmmm, yeah
But I can't understand how power delivery in this day and age could be an issue
If it's not right fix it! With the technology and parts available over the counter nowdays to joe average where be the problem? The engine is only what you make of it
The TS/TM400, though far removed from the RN factory bikes, did infact make very good power. Tuned correctly there aren't too many bikes of the '71-'74 era that can match them for shear grunt