thanks !
this is very interesting : my HDN KL has the same salto of the KX ( the jump is almost the same of the Pretzer ) while the KR is much slower.
so we have two different situations with 3D balls :
1) fast balls rohling ( like K.Otto , Kobisch .... ) with KR much faster than KX and KL even when the balls is brand new : the difference I have noticed in these balls is around 8-10 cm.
2) some rohling balls that become slower after years ( like HDN and others ).
some of the gummi components must be really " unstabil " !
in any case the HDN is a very good ball : I bought 2 KL and in 2006 I changed one with a superfast 085 blau ..
