hi i was having trouble on hills with my DNA 50 slowing to 10mph and revs dropping, so I replaced the stock contraspring with a white makuni rated at 1000rpm. This improved hills somewhat. I have fitted a new polini variator but the kit comes with a blue spring rated 50mm / 20kg. It doesn't show an equivalent rpm rating. Can anyone tell me if this blue polini spring is stiffer or softer than the 1000rated one? Spring appears thinner but it's also a little shorter?
