I know OFF TOPIC
But I did look up your flicr account, some vry nice Bul's are shown there quite interesting!
Any information about your Spanish ride?
And I have an idea why there was welded a second tube to the swing arm. The wheel base
of the TY is very short as an improvement the swing arm can be extended about 25 -30mm.
Normally this is done at the end of the swing arm here it's done with the second axis
very unusual construction.
I saw the other pic's of the Yamaha too ... Well ... this bike needs some serious rebuild ...
thump's up that you will get it sorted ...