Detuning tip/tail on GS cheaters / sport carvers?

[slow-line-fast]

Since forever I've just tuned everything tip to tail. Was recently out on fairly stiff GS 'cheaters' (Nordica GSM piston, 185/20.5) that I haven't skied much yet. They were great in many snow conditions, but on slopes with particularly grippy snow, and only while drifting the top of the turn, the tip and tail were catching and releasing in a rapid, alternating way, creating a weird and unstable chatter. I've not ever had that on my longer radius GS skis (187/26), which I've spend much more time on.

So I think I should detune the tip and tail. How much, and how far back? I'll try 'a little' and keep a gummi stone in my jacket pocket.

 

[François Pugh]

Could be a lot of things causing that catch and release.
Giving you the benefit of the doubt and it's not a technique issue:
Are the very tips of the skis railed?
Have the front of the skis lost some strength- how's the camber?

I would not detune them; if its a problem with the skis you will only make things worse.

 

[slow-line-fast]

Skis have just a few days on them.

Tips maybe very slightly railed, checked with true bar.

Could well be a technique issue (I have many) but I don’t have the problem on longer radius GS skis that are probably a similar stiffness

 

[François Pugh]

while drifting the top of the turn

Simple solution, don't do that!
Technique issues could be your not getting your weight to the tips well enough. It doesn't effect you on the longer, and longer radius, skis because you can't make the catch happen, so there's no release.

Assuming you can make arc-2-arc pure carved turns when you are not trying to drift the top of the turn, which in your case is not that bad of an assumption, the thing is you need to concentrate more on control via tipping and less by weight distribution, i.e. just avoid that exact tipping angle where the skis catch - far less angle when you want to drift and far more when you don't. That criticle angle is going to change with turn radius; the 20.5 m skis are trying to make a shorter turn for a given tipping angle and be more likely to release once it gets dialed in and the angle required for the (now) turning ski increases. The turn will also develop quicker.
In short if you are used to one ski and have some automatic habits, it will take a bit of time to get dialed in on the new ski. (don't ask me about the time I automatically and instantly dropped a 500 cc bike into a double downshift while rev matching for my old 750.)

 

[slow-line-fast]

Thanks, will play with that when next on the skis.

I should have added, I also haven’t had this problem on fis SLs

 

[François Pugh]

It's easier to be precise with shorter skis.

 

[crgildart]

Sounds like the ski is asking for bigger angles than you are tipping them at right now.. Or, the opposite problem, possibly booting out a little bit?

 

[slow-line-fast]

No problem with the GSM when in pure arc to arc carve, problem comes when drifting top of the turn. My longer radius GS skis drift much more smoothly, hence I wonder about detuning the tip/tail of the shorter radius GSM. But improving technique is always the goal anyway

 

[Philpug]

We were jsut on some skis that were way too sharp tip to tail and some slight edge adjustments and a few light passes with a gummy cured all ills.

 

[anders_nor]

Since forever I've just tuned everything tip to tail. Was recently out on fairly stiff GS 'cheaters' (Nordica GSM piston, 185/20.5) that I haven't skied much yet. They were great in many snow conditions, but on slopes with particularly grippy snow, and only while drifting the top of the turn, the tip and tail were catching and releasing in a rapid, alternating way, creating a weird and unstable chatter. I've not ever had that on my longer radius GS skis (187/26), which I've spend much more time on.

So I think I should detune the tip and tail. How much, and how far back? I'll try 'a little' and keep a gummi stone in my jacket pocket.

grippy snow can be challenging, combine with 87 tune and piston plate + heavy rider, imho its just not that easy to not be locked in.

 

[DocGKR]

The Nordica GSR RB FDT in 185/20.5m was the first modern "GS" ski I used after getting the itch 3 years ago to try alpine racing again after a nearly 4 decade lapse. It is a bit wider at 68mm than a true Masters or FIS 65mm wide GS ski. Mine were a bit hard to handle until they got the base ground and a good 0.5/3 tune put on them, as the factory tune was sub-par. I keep my pair sharp to the ends, no detuning. I now use them all over the mountain as a long-turn sport carving ski, as they are very fun, with nice rebound, good edge hold, and are quite manageable in all conditions; however, they do require solid technique, as they are not as forgiving as some of the other recreational pseudo-GS cheaters....

Is your other ski the 187/26m Atomic 65mm wide tweener FIS GS?

 

[slow-line-fast]

Is your other ski the 187/26m Atomic 65mm wide tweener FIS GS?

Yes.

I've tuned both to 1 base / 3 edge.

From my limited time on them, the GSM are great in a carve, but I want to dial back the nervous behavior in a drift. I don't think there is a problem with the ski, but want to see if I can resolve the tune. Problems with the driver can only have longer term solutions.

 

[DocGKR]

For racing, you might want the 187/26m at a 0.5/3. At 1/3 there should not be any difficultly with the Nordicas in a drift. When was the last time they had a base grind? My pair definitely had issues until that was addressed--and many ski shops have no clue how to accomplish that task, so make sure you take them somewhere that actually knows how to ensure a flat base and proper tune....

 

[slow-line-fast]

Factory grind (looks maybe slightly railed in the tip with a true bar, but I've seen far worse), hand tune of the edges, and a couple days of skiing on them.

 

[Tom K.]

We were jsut on some skis that were way too sharp tip to tail and some slight edge adjustments and a few light passes with a gummy cured all ills.

IMO this is not the heinous crime that many make it out to be.

As long as you're subtle about it, there's no real problem in getting it back, so what's to lose?

 

[Philpug]

IMO this is not the heinous crime that many make it out to be.

Yes, there is too much black and white when there are really more shades of gray.

 

[Brian Finch]

If / when you have any question of over skiing, detune the tip!

 

[Wilhelmson]

Did you tune them yourself or did the shop do it? Have you already honed them with diamond stones in case there were some file edges left over?

 

[cantunamunch]

If / when you have any question of over skiing, detune the tip!

You ever do asymmetrical detunes (presumably marking which was and which wasn't)?

 

[Brian Finch]

You ever do asymmetrical detunes (presumably marking which was and which wasn't)?

No, but that is only because I can barely get my boots on the right feet.