Warm water adjustments

[nam1975]

Our water typically goes from 65-70 F to 83-85 as summer warms up.

 

Any tips on both ski and/skier to adjust?

 

I seem to bog down in turns...and end up in the drink more now that it is warmer.

 

I'm ok with wing adjustment and/or removal or a binding tweak. I've never messed with fins much other than initial set up.

 

Thanks Ballers!

[LeonL]

You're gonna get two (at least) theories on the effects on drag based on water temp. So be ready to decipher the results.

[roberto]

Nam , don't be afraid to experiment, you will learn from the experience. Personally I would move both bindings back 1 hole, and then again if not happy. Take notes and evaluate. Within 3 sets you will have formed a better opinion.

 

Skijay's book is definitive on the subject. Skijay put in literally hundreds of sets to develop his knowledge. But you can start too, it will help develop a rounded knowledge of your skiing.

 

Binding position is key to me, the fin setting I can work round. But if your ski is stuck in a hole and stalling you need something more than 0.005" tweak. Subject to style caveats etc. Check out the fin database app and see if you are in the right zone. This is a great tool. Keep notes! Good luck.

 

 

[nam1975]

Thanks all. I did read some past posts on this.

It sounds like I'll start with bindings back.

 

Step 2 would be a little less angle on my wing. It's currently at 8*, so if needed I'll go to 7.

 

 

[LeonL]

What @scotchipman said is correct, despite the majority of skiers claiming that cold water is faster. Science says otherwise. Now the adjustments is where the controversy begins. Some say changing DFT is the key. I think @SkiJay says that is the least noticeable change of the three. Note I said I think that's correct. Memory being what it is.

[markchilcutt]

Move bindings back to lessen tip pressure in warmer water would be the first and easiest move. You can also move your Fin back in small .005 increments in conjunction with the binding move. Just moved bindings back last week with water hitting into the 80's. All is well again.

[skibug]

Take out length and add depth....3:1 ratio. So, for every .003 you take out in length, add .001 in depth. This keeps your fin area relatively neutral.

[Jmoski]

@LeonL - IMHO I think the 3 science observations above actually supports skiers experience of cold water feeling faster...

 

The key is surface tension and not the friction between the ski & the water.

 

The greater the surface tension, the higher pressure the skier can exert against the water without it "giving way" which is what happens when you apply enough force to redirect it - or in other words breaking the tension as you carve up that wall of water.

 

Colder water --> higher water tension --> Higher pressure --> faster cross course speed!

[bigtex2011]

I would NOT agree with moving the fin back. Bindings back an 1/8 to a 1/4. Our water temp is 95

[MISkier]

@Jmoski, that has been my assertion as well. Many say they like warmer water because their ski turns better. Why does it turn better? Maybe because it sinks in and slows down at the turn more than in cold water.

[SkiJay]

@skibug We finally got science to give us at least one definitive answer on fin area.

 

The head of engineering at the top team in Nascar took a swing at a formula that calculates fin areas after changes. Even he came to the realization that a simple formula is impossible because of the lack of any consistent fixed reference point.

 

But one of the things he did establish is that adjustments to FL change fin area vary nearly exactly ½ as much as adjustments to FD.

 

When tuning, however, keep in mind that while fin area and smear will remain virtually unchanged using 2:1, the ski's roll and tip engagement characteristics will change.

[SkiJay]

@nam1975 Regarding the adjustment of setups for warming water, the short answer is that any setup that works well In cold or cool water will remain a good setup in warm or even hot water. (This relationship is less reliable when transitioning from warm to cold water.)

 

Yes, the ski rides differently as the water warms up, but there is little to nothing you can do to compensate for this with ski setup. You can improve space at the expense of turn radius, or vise versa. But you'll most likely be undermining your overall setup with these tradeoffs—assuming you had an optimized setup to start with.

 

And if you do want to test changes, use a second fin and fin block so you can compare the two setups back-to-back within 10 minutes with the same driver. Trying to draw meaningful conclusions one day to the next is touch, even for the best skiers.

[gavski]

Is there a case when the water get s so warm that the skis feels like it is 'ploughing' becaus it is riding so low in the water??

 

I am regularly transitioning between 66-94 degF water. The ski is dialled in - i ski @36, and expect to run 1/2way down 38...but since the water has reached into the 90's, i am really struggling to get my ski moving. At the colder temps, reducing 1deg of wing helps to restore the 'feel'.. would this work at the 'hotter' temps??

[Chef23]

I was driving for a friend who is a mid 38 off skier and he moves his bindings back 1/8" and takes a 1/2* out of his wing for warmer water and leaves the fin unchanged for warmer water.