Hi Harald
I can appreciate your hesitation to cut a brand new pair of boots/springs, I too had the same reservations. Looking back on my experiences I would suggest you do a few things different than I did. Here are a few ideas that may help to ease you into your new boots. The idea behind the test/steps is to start with a stiffer spring setting and slowly test slightly softer settings until you find one that is best suited to you.
Test 1
First ride your NW boots without any modifications at all, get to know them a bit, let the liners break in. I too did this. Spend a lot of time with the forward lean settings first, add the small 'nut' to the threaded adjustment so that you can make very accurate adjustments that will not move as a result of vibrations. If your range of motion feels restricted, continue to play with the lean. If the restricted feeling continues, go to test two.
Test 2
Cut ONLY the yellow (stiffest) bottom spring as Patrice did (1/3 - 2/3). Install the springs in the following way:
Very bottom spring - 1/3 Yellow (Heel Side)
Stack top springs - 2/3 Yellow + full UNCUT blue NW spring on top
(The stacking length of the Blue+Yellow is not a prefect match to the rod length, but still works well. There is .5cm of free play, that you may really like.)
This will allow for a greater range of forward movement. If the restricted feeling continues, go to test three.
Test 3
Leave the bottom 1/3 spring.
Leave the top, full length UNCUT, blue NW spring
REMOVE only the 2/3 Yellow spring
Install a SOFTER spring to replace the removed 2/3 yellow spring.
I would buy springs that are EXACTLY the same dimensions as the stock blue NW spring, but with a softer flex. Cut this new spring exactly in half.
Stack the stock Blue NW spring and the new 'cut in half' spring.
This will allow for an easier range of forward movement. If the restricted feeling continues, go to test four.
Test 4
Cut and install the NW springs in exactly the same way that Patrice has done in the previous posts (picture). If the restricted feeling continues, make small cuts to the tongue of the NW boots. Cut the tongue where the natural bending point is.
Some Background Info
This summer I pondered machining a longer 'rod' for my NW boots. This would enable me to use the stock NW yellow spring (heelside) and still permit me to have a longer range of forward motion (toeside). After a good e-mail exchange with Jacques in learned that the original modification served two purposes: 1) A longer range of forward motion. 2) J&P found the original stock uncut yellow NW spring created too much movement during a heelside EC turn. The longer backward range of motion caused J&P to loose their balance backwards during a heelside. Cutting the yellow spring made it harder and solved the balance problem.
Hope this helps
Rob