Question for the Nerdy Kid if you may. Skiing the CS130 with a zipfit for the past season and a half (C19).
Really really like the fit, response. 5'11" and 160lbs me is and Most of the time the flex pattern is spot on with little to no distortion in the clog......but......there are times when it feels maybe a little too stiff to initiate the flex. I have considered relieving the V but I would like to read your thoughts on the leverage effect of increasing the forward lean angle with, I think they (you) call it the power shift? I have tried this with the thick shim at the rear between the clog and the cuff and still only one cuff bolt and it indeed changed, softened, my perceived feel of the flex pattern. No real variation in the outside air temperature or power strap when A-B ing the change. Thanks for any thoughts.
I have tried the thicker shim in my CS130's and also cut the V down some. I also keep the power strap loose around the shell, but snug around the liner (upper band with velcro adjustment). I agree cutting the V is the biggest change, but I would add that it does make a significant change, so as ONK said, do it in small steps till you get "soft enough". Here is what I experienced through my "dialing in" process this past season.Is using the thicker, 5mm shim in the back solving the issue for you? Or is it still a little too stiff?
If you are wishing the boot initiated the flex more easily, I would have the shell Vs cut down a bit. Perhaps just a couple of millimeters at first, then see how that feels. If not enough, do a couple more. I think you will find this to be the best way to arrive at your desired flex pattern because even though it's non-reversible, you are taking off so little that it won't feel like you've done too much too soon.
1. Thicker shim - 18 deg forward lean. I love this lean angle, not too much for me (I have 36" inseam) and it puts me in the almost perfect skiing position. It also means I don't need to flex the boots as much to get the same range of downward body motion. I look at it as I naturally want to flex up and down a certain amount. If in a very upright boot, then you are too straight and need more downward or forward flex range of motion ROM from the boot. If too far forward, can't straighten up enough and you get thigh burn too quick. The CS's 18 feels just right to me. It might have softened the boots flex a little, but not much that I noticed. Personal preference on the forward lean setting for sure.
2. The bootfitter suggested I use a single screw in the top hole on the back of the boot. After installing the 18deg shim, he drilled a hole and put the screw in the top hole. Plugged the bottom hole. Again, minor change but probably something additive.
3. Keeping the power strap loose around the shell, but snug on the liner makes a noticeable difference in stiffness when deep into the flex. It ramps up much stiffer with the strap snug around the shell too. Its a nice feature of the dual zone strap. I have ordered the new professional elastic dual zone strap for next year and that should be even better. Its PN is AZE001686.
4. This plastic (PU) is very sensitive to temperature, as are all high end racing boots that use PU. Its a compromise to get the flex just right. I guess the best target is a little too stiff when really cold and a little too soft when really warm. A plastic not affected by temp but with the identical properties of PU is the holy grail that doesn't exist yet. Girilimid is a pretty temp constant plastic, but a lot different feel than PU. The Hawx XTD touring boot I also own is Girilimid.
5. Cutting the V. I have done this on my Lange RS140 boot and it did not make a large difference. I also did it on my CS130 and it had a much bigger effect. The clog has 3 V lines molded in, I cut to the second line, and I really like the results. Only on really cold days do the boots get overly stiff now. In spring skiing they were perfect. I did it myself with a dremel tool. The boot still has zero shell distortion. I also tried loosening the top buckle one notch looser than normal when skiing moguls and I liked that effect as well. With the top buckle looser, you have more ROM with the tongue padding compression. It really doesn't change the boot flex, but it delays it a few degrees and you don't have to flex as deep into the boot, so its overall feel is softer. Still perfect foot hold even with the cuff slightly looser. When on groomers I snug it back up to normal for a little quicker response. Here are some pic's.
My old Lange RS140's