Seeing the fact of vtr clutch covers being so expensive..can an rc51 clutch cover be used?

 

No.

 

What are the differences? They appear fairly identical

 

Completely different bikes and motors

 

Perhaps you are mistaking a VTR1000 for a VTR1000F and thinking the covers are the same...when looking for them on line and thinking they are "fairly identical"?

Pretty sure if you were to see a RC51 and SH cover side by side, you would never mistake them as interchangeable...