Wirth Fork Springs

Has anybody installed the Wirth progressive fork springs from Tourtech?

Does anybody have any opinions as to whether or not they're Wirth it

Whats the difference between the 047 and o48 versions (please don't say one is the left and the other the right?)

I have installed the Progressive Fork Springs, & they do improve the front end.

I did not, however, pay TT prices for them, but got them from www.hagon-shocks.co.uk for £62.50 & free UK postage.