thx graham, yeah jbot linked to his thread
it i think he initially used a gy? spring then went to a zuma/jog spring. which is what ive bought.
you are right, all of this stuff has been asked about before and is old news to most but i'm new to mobylettes and a bit of a noob. i find if someone mentions a solution i then use the search (not only on here) to find good info.