You said:
since the e27 is a masthead rig am i bending the mast with the backstay or just compressing the mast.the main sail is not in very good shape so it is hard to tell any difference.any advise on proper adjustment with the masthead set up would be appreciated.
>>>>>>>
Well, whatever else you tension with the backstay, I am sure you are not compressing that aluminum spar. (!)
The cabintop, compression post, whatever's under the post: maybe... but not the spar.
If your main is bagged out, have a sailmaker quote you on a recut and also a straightforward opinion on whether the sail is worth spending any dollars on. If the main is both old and baggy, get a new main pronto. The "fall discount" season for new sails is ending momentarily.
Your reference to using the adjustable backstay to flatten the main by bowing the mast forward a few inches is correct. Trouble is, when the main gets too baggy, this adjustment still will not flatten it enough for heavy air, which was the idea in the first place.
If this does not help, please refine your question and post again...
Happy Holidays,
Loren