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# Point Of Diminishing Returns With Regards To Ski Length - Page 3

At the link below, in paragraph 2.2, you'll find the following words

In other words it can be used to describe the idea that in a carving turn the front part of the ski digs the track and the rear part of the ski follows this track. Shear force is modelled based on metal cutting theory (Shaw 1984).

http://sport1.uibk.ac.at/SkiProTech/Doc/Abstract%20China.pdf

The article isn't necessarily talking to this conversation but you see that even scientist use the technical term of "digs in" .

Ken

Chiming in to confirm what Oison said:

The boat length formula is basically how fast the displacement type boat can go before it get's sunk by the water it's displacing.  It is not relevant to skiing, nor by the way, to planing boats.

From my experimentation, the ski length (comparing 208s to 165 skis) did not have any significant affect on maximum speed achieved on small hill where the maximum speed was in the 60 mph ball park.  Wind resistance was such a big factor, it overpowered the ski factor. (although  60 mph did feel slow on the SGs and very fast on the SCs).  This experiment did not involve any gates, just maximum achievable speed on a given hill.

It seems intuitively obvious that if your ski is so short and forces so great that float is a factor, gs skis will be faster than snow skates.  How big a difference this makes on a course is not likely to make it a major decision maker; by the time the effect is noticeable, the other effects (skill required to manage fore aft balance for example) will have long ago stopped your progression in the short direction.

Usually "taper" refers to the difference between tip and tail (leaving the waist out of it).  Although you can talk about taper from tip to waist and from waist to tail, you have to be very careful with the words you choose when using the term in that context.  Just say'n.  There was a lot of talk about dual radius skis from the marketing gurus in the last few years, but truth be told Taper has been around for a long long time.

Wider tips do make initiation easier.  Wider tails do make holding on to the turn easier.  There are secondary effects, like a wider tail will help put some counter torque on the tip when the tail interacts with a hard surface, but the primary factors are so great that secondary factors such as how does a wider tail affect initiation via torque balance etc. are like trying to separate fly scat from pepper while a pirate is making off with your spice ship.

What was the question again?

Please rank in terms of importance to you:

Wining Nastar races.

Having fun free skiing

What is your favourite speed while free skiing?

How much do you value making short turns while free skiing

PAY DIRT!!!!!!!!

This should keep me busy until September!!!!

http://e-collection.library.ethz.ch/eserv/eth:28070/eth-28070-02.pdf

Du hast  Recht.

Although, the devil is in the details with these finite element models....

Quote:
Originally Posted by Ghost

What was the question again?

Please rank in terms of importance to you:

Wining Nastar races.

Having fun free skiing

What is your favourite speed while free skiing?

How much do you value making short turns while free skiing

So I'll answer above but first remind that the original question was looking for the formula and not a recommendation.  What I want to use the ski for shouldn't matter.  It's how to determine the size of the ski once you know what you want it for.

The original question :

"Is there a point of diminishing returns on ski length? I'm mostly gearing this towards race skis, mainly recreational race skis."

What I was really trying to figure out, was at some point, the skis become more work than fun.  I was thinking that there is a point that if I was on a 175 cm ski or a 185 cm ski, the extra float/glide/benefit or whatever, would be so insignificant, that I didn't care.

As for what I want the ski to do:

Have fun free skiing ripping around the mountain.

Though I will probably use it in NASTAR, it will be for training (i.e. get me ski legs back).  If I want to go faster in NASTAR, I will use my GS race stock skis.  I consider the ability for the ski to perform in NASTAR also as a silver lining.  I usually spend December and early January race training and then plan for results in late January and February.  I was on track with that this past year until I was early in a gate and put my race ski between the two poles (tore my acl, mcl and lcl).  I strongly recommend not doing that.

Though the accident ended my season, it was a milestone for me because I was carving a 21.2M race stock ski with a race plate so well that 4 gates from the end, I was early and not late (as usual).  My race friends that saw me racing said I was ripping and looked great right up to that gate.  I was finally keeping up with (though still behind) the top racers at the mountain.

I only bring all that up so you know that I learned how to do that by spending two weeks on my 155 SL race skis practicing my carving and racing in the gates, then another two weeks on the GS race skis.  I'm planning on doing that again this year.  But again, this ski being able to do that better than the 155 SLX is a secondary thought.

I'm also looking training for L2 this season and testing next season.  I will need to demonstrate short, medium and long radius turns and go in the bumps .  I'm not even a weak bump skier so in my head a shorter ski will make it easier on me to learn that.

So free skiing and training for L2 would be the primary reason for the skis.  We get a bit of ice around here and I love the edge hold that race skis give so I would like to stay within race skis whether they are cheater or not.

I have no idea what my (actual) favorite speed is but I get teased by the other instructors about always wanting to ski fast.  I do know that as I get better the speed increases.  I mostly work at carving and because I love to race, I do like going fast.  I spent the previous season learning how to control my speed and can now do that.

Ken

I think there is a chicken and egg problem with ski length.  Some of the performance differences are inherent in length, but a lot of them are design choices.  And people who buy longer skis expect them to be different (stiffer, usually, for example) so the designers make them that way.

Let's not forget what my comments about the tip digging in were in response to.

Oisin said a Slalom skis tip diggs in more them a Gs ski and that is what makes sllaom skis slower in a race course. I still don't beleive that this is the cause of slaloms being slower in a course.

Does the article prove this to be true?

He didn't say "digging in", he said the tip digs the track and the rest of the ski follows in a carved turn, I sadi that about 10 posts ago!

Oisin was sying the tip digs in more then the rest of the ski ina slsom then a gs and this the reason it is slower!

Quote:
Originally Posted by L&AirC

At the link below, in paragraph 2.2, you'll find the following words

In other words it can be used to describe the idea that in a carving turn the front part of the ski digs the track and the rear part of the ski follows this track. Shear force is modelled based on metal cutting theory (Shaw 1984).

http://sport1.uibk.ac.at/SkiProTech/Doc/Abstract%20China.pdf

The article isn't necessarily talking to this conversation but you see that even scientist use the technical term of "digs in" .

Ken

Quote:
Originally Posted by Ghost

Chiming in to confirm what Oison said:

The boat length formula is basically how fast the displacement type boat can go before it get's sunk by the water it's displacing.  It is not relevant to skiing, nor by the way, to planing boats.

Ghost, understand about the bow and rear waves etc. And will (reluctantly) accept that it's of minor or no relevance to groomers. But this has me thinking about powder. In real pow, you do in fact see a bow wave and wake at speed. And the ski is not planing, it's down in the snow, just like a boat hull. I also note the design of the Dynastar Watea shovels, which they state is derived from boat hulls, and will work the same way in soft snow. So is your argument that either bow waves and wakes in powder are illusions, or that skiing powder is not skiing ?

Quote:
Originally Posted by Atomicman

He didn't say "digging in", he said the tip digs the track and the rest of the ski follows in a carved turn, I sadi that about 10 posts ago!

Oisin was sying the tip digs in more then the rest of the ski ina slsom then a gs and this the reason it is slower!

I posted that because you seemed to be hung up on the term, and someone is going to have to prove that a ski with as much taper as a short SL ski, not matter the length, doesn't dig in more than a ski with less taper.

In one of my posts, either last night or this morning, I stated that the tip has to be in deeper than the waist, and in order to carve the waist has to come in contact with the snow.  Since a ski can't be made to bend enough for the edge to be flush with a flat surface, the tip and tail have to dig in more, so there is more digging in on short SL skis that have a lot of taper.

Oisin, and originally me, believe it was more of a pounds per square inch issue, where the same pressure is exerted on a shorter ski so it would dig into the hill more.  I don't believe this any more because I remembered the base still makes a platform and there is more area per square in in a curvy ski in contact with the snow than most would think.

This is the part that is the chicken and the egg; shorter skis usually have more taper so they dig in more due to the taper.  So people gravitate, like I did, to the shortness of the ski causing it and forget about the taper.

A 180 cm ski will probably be close to as slow as a 155 cm ski if the tapers are proportional when compared to a 180 gs ski.

Ken

slaloms have less taper angle in the tail nad less taper angle between the tip and tail. In other words a GS ski tapers more!  Taper means from wider to narrower so again the closer the tail dimension to the tip the less taper angle the ski has.

Or from waist to tail,  a wider tail tapers less so it has less taper angle a narrower tail tapers more so it ha smore taper angle.

The tip digging in still is not the reason slaloms are slower then GS !

Quote:
Originally Posted by L&AirC

I posted that because you seemed to be hung up on the term, and someone is going to have to prove that a ski with as much taper as a short SL ski, not matter the length, doesn't dig in more than a ski with less taper.

In one of my posts, either last night or this morning, I stated that the tip has to be in deeper than the waist, and in order to carve the waist has to come in contact with the snow.  Since a ski can't be made to bend enough for the edge to be flush with a flat surface, the tip and tail have to dig in more, so there is more digging in on short SL skis that have a lot of taper.

Oisin, and originally me, believe it was more of a pounds per square inch issue, where the same pressure is exerted on a shorter ski so it would dig into the hill more.  I don't believe this any more because I remembered the base still makes a platform and there is more area per square in in a curvy ski in contact with the snow than most would think.

This is the part that is the chicken and the egg; shorter skis usually have more taper so they dig in more due to the taper.  So people gravitate, like I did, to the shortness of the ski causing it and forget about the taper.

A 180 cm ski will probably be close to as slow as a 155 cm ski if the tapers are proportional when compared to a 180 gs ski.

Ken

Quote:
Originally Posted by Atomicman

slaloms have less taper angle in the tail nad less taper angle between the tip and tail. In other words a GS ski tapers more!  Taper means from wider to narrower so again the closer the tail dimension to the tip the less taper angle the ski has.

Or from waist to tail,  a wider tail tapers less so it has less taper angle a narrower tail tapers more so it ha smore taper angle.

The tip digging in still is not the reason slaloms are slower then GS !

OK.  I had not figured out the correct use of the word "taper".  Thank you.  I now know.

This is what I'm talking about, the numbers in yellow:

Notice that the difference between the Men's FIS SL ski and the Men''s FIS GS ski?  That is what I'm talking about when I incorrectly use the word "taper".  Since 52.3 is greater than 33 (at least it is when I'm not skiing ) the SL tip and tail are going to DIG IN more than the GS tip and tail.  Does that clear up the point I'm trying to make?  When you carve or even on dry land, bend the ski, the difference will seem less significant but the tip will still be in the snow deeper than the waist.  You can't get the edge flat unless the ski is so soft you can't break it.  I tried it on a GS race ski and could NOT do it.  It will break first.

I'm not trying to argue.  Only trying to sort this our via the internet, which is proving difficult.

Please let me know what the correct term for what I'm describing is.

Ken

I look at taper angle in % not hard numbers, I took my Head i.SL Rd's and yes you can touch the waist and have the entire ski touch, the problem is you are trying to push it straight down at what???  a 90 degree angle???  iI you bend the ski in the middle while up on edge it is extremely easy to have the entire edge touch at once.

think about it the forces when you are skiing decamber the ski and this is what makes the entire edge cantact. And the ski bends into an arc.

So let's take Oisin's Injected snow (have you ever skied on it?) exmple, no part of the ski is going to penetrate that but the ski is still bent into an arc and slalom's trun more sharply then Gs's.

It is the shape of the ski up on edge and the tip and tail are not in the snow any fartehr then the rest of the ski.

If the tip and tail dug into the snow farther as you tipped your ski up, what would cause it to bend further as you increased the edge angle???

the ski is not designed to bend the direction you are trying to bend it! It is designed to bend into an arc on edge as you push the center away from you.

Quote:
Originally Posted by L&AirC

OK.  I had not figured out the correct use of the word "taper".  Thank you.  I now know.

This is what I'm talking about, the numbers in yellow:

Notice that the difference between the Men's FIS SL ski and the Men''s FIS GS ski?  That is what I'm talking about when I incorrectly use the word "taper".  Since 52.3 is greater than 33 (at least it is when I'm not skiing ) the SL tip and tail are going to DIG IN more than the GS tip and tail.  Does that clear up the point I'm trying to make?  When you carve or even on dry land, bend the ski, the difference will seem less significant but the tip will still be in the snow deeper than the waist.  You can't get the edge flat unless the ski is so soft you can't break it.  I tried it on a GS race ski and could NOT do it.  It will break first.

I'm not trying to argue.  Only trying to sort this our via the internet, which is proving difficult.

Please let me know what the correct term for what I'm describing is.

Ken

I think a lot of the reason that you see so much taper in GS skis is because it allows them to make a tip that really pulls without breaking the radius rules. I think they'd probably like to give it more tail too, but a more balanced ski with the same radius wouldn't pull you into the turn as hard.

Anyway, L&AirC, I don't think that the math is helping find you the right ski. I think it's steering you toward the wrong ski. Some of us have been where you are, some of us help skiers that are where you are now, and I don't think many of us would choose or recommend the skis you seem to be gravitating towards. I say forget the math and go with intuition, and learning from the mistakes of others.

Sorry to be so obstinate, but actually the tip on the curren tFIS gs skis in no wider then then they ever were ((during the shaped ski era)  and if so by a very small increase. No,  the waist is much wider! Look at the 188 FIS ski above it has a 68MM waist, that is as wide as an old all-mountian mid-fat.  And now DH's and Sg's are as wide as 70MM

My non-FIS Atomic D2 179 has a 70mm, that is as wide as an old R:11.20 and R11 Beat-Puls a full out all mountain mid-fat!

Shaped GS skis a few years ago had waists of 63-65MM  (I think Deborah Campanogni's old Dynastar in the 1998 was 62mm at the waist (and I thought she got busted for having a ski that was too narrow at the waist. I have old Atomic 10.22 Beta Race that between 99mm and 101mm sitting in my garage, but the waist was 65mm.

I just measured a pair of 2004 186cm World Cup Atomic Gs11. 100mm in the tip 64.5 in the waist

Quote:
Originally Posted by epic

I think a lot of the reason that you see so much taper in GS skis is because it allows them to make a tip that really pulls without breaking the radius rules. I think they'd probably like to give it more tail too, but a more balanced ski with the same radius wouldn't pull you into the turn as hard.

Anyway, L&AirC, I don't think that the math is helping find you the right ski. I think it's steering you toward the wrong ski. Some of us have been where you are, some of us help skiers that are where you are now, and I don't think many of us would choose or recommend the skis you seem to be gravitating towards. I say forget the math and go with intuition, and learning from the mistakes of others.

I don't think I said the tips have gotten wider.

You didn't?????

Quote:
Originally Posted by epic

I think a lot of the reason that you see so much taper in GS skis is because it allows them to make a tip that really pulls without breaking the radius rules. I think they'd probably like to give it more tail too,

Quote:
Originally Posted by L&AirC

So free skiing and training for L2 would be the primary reason for the skis.  We get a bit of ice around here and I love the edge hold that race skis give so I would like to stay within race skis whether they are cheater or not.

I have no idea what my (actual) favorite speed is but I get teased by the other instructors about always wanting to ski fast.

#1 The video was useless.  A really good skier on *perfect* snow carves at medium speed on 165s. On crud on my 195 (sitskiing) even I would beat him, an amazing proposition since I'm a poor skier (wasn't always) because his skis won't rail on crud.

#2 Lose your instructors.  Most of the joy of skiing IS speed, a different speed and pattern for each person at a given time.

#3 Free skiing involves variable snow, for that you need to go longer.  Look, you'll probably find a 155-170cm slalom ski that nearly maximizes speed with *your* dynamics if you demo a lot.  But it will be a lot less fun than longer skis in other applications.  Short skis are great for slalom and ok for billy-goating, not great for other uses.  If you demo skis of widely different types in different conditions, you'll learn what works best.  Since as a teacher you'll need to ski switch a lot, a semi tail rise is good.  But that won't help you carve.  As someone versed in physics, you must realize that your height, size, ability, and average ski course are only some of the variables to consider.  More important are qualities unique to your mind and body that you cannot quantify.  A certain profile of vertical and longitudinal and torsional stiffness, length, radius, camber, taper, damping, base and edge tuning, and all the other characteristics I can't recall will give the ski a certain feel TO YOU.  THIS is why your formula quest is useless beyond its current state, unless you want to make a lifelong devotion to this topic.

Listen to the really good skiers here like BWPA, they learned something on the way.

Quote:
Originally Posted by epic

I think a lot of the reason that you see so much taper in GS skis is because it allows them to make a tip that really pulls without breaking the radius rules. I think they'd probably like to give it more tail too, but a more balanced ski with the same radius wouldn't pull you into the turn as hard.

Anyway, L&AirC, I don't think that the math is helping find you the right ski. I think it's steering you toward the wrong ski. Some of us have been where you are, some of us help skiers that are where you are now, and I don't think many of us would choose or recommend the skis you seem to be gravitating towards. I say forget the math and go with intuition, and learning from the mistakes of others.

+1

On the other hand you could probably get 164 Bros and be happy everywhere : )

Edited by whippersnapper - 7/17/11 at 6:08pm
Quote:
Originally Posted by Atomicman

You didn't?????

Nope. I didn't say that they have gotten wider over time I said that they have taper and why I think they have it. Anyway, I'm really not interested in arguing the minutiae of GS skis.

The various forces including the skier's weight are resolved into an angle that varies throughout the turn. ideally the skier'd body aligns with the resultant angle and so no skidding. The weight will act upon whatever is bearing on the snow. If that is mainly the edge and a little bit of base then that is where the weight is acting. Perpendicular to the base would be the ideal I guess. think you may be  right that weight is likely the decision maker regarding speed skate length although skate shape and turn radius are factors there also. Someone more sufficiently anal will undoubtedly explain this better than I.

Oops I think this discussion has gotten way ahead of me!  I was replying to something on the last page I think.

Edited by oisin - 7/17/11 at 6:15pm

Did too!

Quote:
Originally Posted by epic

Nope. I didn't say that they have gotten wider over time I said that they have taper and why I think they have it. Anyway, I'm really not interested in arguing the minutiae of GS skis.

Yeah, Get out your ouija board and see if it'll tell you what to ski on. Ask your wife, women have great intuition!

Jeeeezuz, go demo some skis for Chrissake! I told you that in the 13th post of 82. Ya gotta go ski on some shit man!

Quote:
Originally Posted by whippersnapper

#1 The video was useless.  A really good skier on *perfect* snow carves at medium speed on 165s. On crud on my 195 (sitskiing) even I would beat him, an amazing proposition since I'm a poor skier (wasn't always) because his skis won't rail on crud.

#2 Lose your instructors.  Most of the joy of skiing IS speed, a different speed and pattern for each person at a given time.

#3 Free skiing involves variable snow, for that you need to go longer.  Look, you'll probably find a 155-170cm slalom ski that nearly maximizes speed with *your* dynamics if you demo a lot.  But it will be a lot less fun than longer skis in other applications.  Short skis are great for slalom and ok for billy-goating, not great for other uses.  If you demo skis of widely different types in different conditions, you'll learn what works best.  Since as a teacher you'll need to ski switch a lot, a semi tail rise is good.  But that won't help you carve.  As someone versed in physics, you must realize that your height, size, ability, and average ski course are only some of the variables to consider.  More important are qualities unique to your mind and body that you cannot quantify.  A certain profile of vertical and longitudinal and torsional stiffness, length, radius, camber, taper, damping, base and edge tuning, and all the other characteristics I can't recall will give the ski a certain feel TO YOU.  THIS is why your formula quest is useless beyond its current state, unless you want to make a lifelong devotion to this topic.

Listen to the really good skiers here like BWPA, they learned something on the way.

+1

On the other hand you could probably get 164 Bros and be happy everywhere : )

Quote:
Originally Posted by Atomicman

Yeah, Get out your ouija board and see if it'll tell you what to ski on. Ask your wife, women have great intuition!

Jeeeezuz, go demo some skis for Chrissake! I told you that in the 13th post of 82. Ya gotta go ski on some shit man!

My wife can't stand skiing and I save the ouiji board for work.

Not sure about where you are but it's 10PM here and almost 80 F.  If I want to ski, it would have to  be on shit.

I have close to 130 days to think this through.  This pursuit will keep me busy until then.

More than likely I'll have made my decision long before that.

Sometimes you have to do some research, make a plan and act on it.  To do a demo correctly, would take me a season.

If I don't get the right ski, I'll sell it and buy another.

I still believe science can be applied.  There's no way it can't be.  We (I) might not know what it is yet, but once discovered it will work.

Quote:
Originally Posted by whippersnapper

#1 The video was useless.  A really good skier on *perfect* snow carves at medium speed on 165s. On crud on my 195 (sitskiing) even I would beat him, an amazing proposition since I'm a poor skier (wasn't always) because his skis won't rail on crud.

#2 Lose your instructors.  Most of the joy of skiing IS speed, a different speed and pattern for each person at a given time.

#3 Free skiing involves variable snow, for that you need to go longer.  Look, you'll probably find a 155-170cm slalom ski that nearly maximizes speed with *your* dynamics if you demo a lot.  But it will be a lot less fun than longer skis in other applications.  Short skis are great for slalom and ok for billy-goating, not great for other uses.  If you demo skis of widely different types in different conditions, you'll learn what works best.  Since as a teacher you'll need to ski switch a lot, a semi tail rise is good.  But that won't help you carve.  As someone versed in physics, you must realize that your height, size, ability, and average ski course are only some of the variables to consider.  More important are qualities unique to your mind and body that you cannot quantify.  A certain profile of vertical and longitudinal and torsional stiffness, length, radius, camber, taper, damping, base and edge tuning, and all the other characteristics I can't recall will give the ski a certain feel TO YOU.  THIS is why your formula quest is useless beyond its current state, unless you want to make a lifelong devotion to this topic.

Listen to the really good skiers here like BWPA, they learned something on the way.

+1

On the other hand you could probably get 164 Bros and be happy everywhere : )

#1 The video was made with a different intent.  At the time I was trying to figure out a different way to pick the binding location.  When I had the gs ski on the bench, I had it at an angle on its side and it was supported at the base towards the tip and tail.  I used a 4x4 under the strap to press the center of the ski.  That was the closest I came.  I tried several different methods to include bracing the tip and tail and pressing all my weight at the center of the ski.  Still could not get the entire running surface to touch the bench top.

Anyway, after cranking down on the strap one time, I realize that when it let go, it was going to snap, so I positioned my daughter at a safe distance with the video camera.  I originally posted it to show the energy a ski stores.

I posted the video in this thread just to show that I really do stuff like that.

To do a demo correctly will take you part of 1 day!

i did it by skiing on 3 skis!  took about 2 hours including lift rides!

And the my ouija board post was directed to Whippersnapper! (I was not hammering you LAC)

Quote:
Originally Posted by L&AirC

My wife can't stand skiing and I save the ouiji board for work.

Not sure about where you are but it's 10PM here and almost 80 F.  If I want to ski, it would have to  be on shit.

I have close to 130 days to think this through.  This pursuit will keep me busy until then.

More than likely I'll have made my decision long before that.

Sometimes you have to do some research, make a plan and act on it.  To do a demo correctly, would take me a season.

If I don't get the right ski, I'll sell it and buy another.

I still believe science can be applied.  There's no way it can't be.  We (I) might not know what it is yet, but once discovered it will work.

Edited by Atomicman - 7/18/11 at 9:15am
Quote:
Originally Posted by Atomicman

To do a demo correctly will take you part of 1 day!!!1

i did it by skiing on 3 skis!  took about 2 hours including lift rides!

And the my ouija board post was directed to Whippersnapper! (I was not hammering you LAC)

That will be 1 day after 130 days.

I haven't narrowed down to three skis yet.

That's OK.  I didn't think you were.  I still save the ouiji board for work.

Quote:
Originally Posted by L&AirC

BPA,

I know what people do.  What I'm asking for is why other than that's what all the kids are doing.  If the skis are all 188-194, they are probably FIS.  You can't tell me that someone that is 5'6" and 180# on Fischer WC 188's and someone that is 6'2" and 220# on the same ski are getting the same thing out the ski for the effort put in.  The 5'6" person has to be working a lot harder.  Why should a 5'6" person buy a ski that long other than they are FIS if they work just as well for someone taller and heavier.  If the 188 is right for the smaller skier above, shouldn't the larger skier want a ski that is proportionally fit?  Most FIS GS skis are all within a couple inches (even Fischer's GS WC only spread 4 inches) of each other but most skiers aren't.  The forces and leverage each is able to apply to a ski have to vary quite a bit.

So, if there aren't any FIS rules, how do you figure the optimal ski length?

once you get to the fact that most skier regardless of size "turn force" at speed is pretty much the same.  IE the 180lb person and 220 lb person are actually pulling roughly the same force though turns. The limiting factor is going to be quad strength/weight ratio.

Let me tell you a story about perfect engineering. Prior to ever skiing, prior to ever posting on this board I was taking Mech. Engineering at the University of Pittsburgh. I was a member of our SAE team. For those that do not know what the SAE competion is build a small open wheeled race car, powered by a 600cc sport bike motor. My team insisted on two things the practical side of me saw no point in exploring. First they wanted it be as light as possible. They figured out the yields of our materials, different designs  for our frame work, and roughly how much force would be exerted on the car. They built the lightest car they could possible build. I said we should throw all the number out and build its strong add at least 50 percent more strength than we ever thought we would need.  They also wanted a perfect neutral car with no detectable under steer or over steer.  The thing is when actually driving something imperfection is faster in regards to handling. A little bit loose with a progressive breakaway point is alot faster than a neutral car. I fought them with this to the bitter end but their thick fing skulls could not get though their heads on why this was not a good idea. Number do not lie right?

So I was far and away the best driver on our team. During testing the car was flat out undrivable. When you got anywhere near the limit the neutral car would break its front tires loose without any warning but as soon the understeer started it would quickly go to snap oversteer. At least at the test and tune I made the car handle progressively loose and at least made it drivable. It had less overall grip but was now faster because me and the other drivers could drive it. Not that it mattered though, the cars frame broke just prior to the competition and we never got to race it.

STUPID ENGINEERS.

numbers are not as important as people make them out to be, and over engineering by people with very limited skills is a horriable idea. We probably would have won if the dam car did not break just because my driving skill was superior to anyone else in the contest.  L&AirC what your doing now is the same thing as these guy who ultimately failed at their goal. Your letting numbers get in the way of a practical choice that was already made much eariler in the thread. You just way to smart(or is it stupid)  to go that way, because its what are the cool kids with no data is doing. You know why they do it? because it works.

Quote:
Originally Posted by BushwackerinPA

I fought them with this to the bitter end but their thick fing skulls could not get though their heads on why this was not a good idea. Number do not lie right?

STUPID ENGINEERS.

numbers are not as important as people make them out to be, and over engineering by people with very limited skills is a horriable idea.

I'm shocked!  Especially with your proven track record of diplomatic communication skills and humble approach.

I'm slightly confused by how the two highlighted statements ended up in the same post.  Seems like you're arguing with yourself.

OK.  All kidding aside.  This is just an exercise for me and apparently of several others to learn from.  It's summer.  This is what I do in the summer.  Maybe there isn't an answer and anytime someone wants to buy a ski they should 1) ask a forum or 2) go demo.  Some how manufactures use data to figure out what to make.  Consumers should be able to use some data to figure out (at least a small pool) what to buy.

Ken

Edited by L&AirC - 7/18/11 at 7:20pm

All things being equal a longer ski glides better because it has more wetted (lubricated) running length and is more streamlined compared to a shorter ski. There is a reason that XC skis are still 210 cm X 48mm wide.

Maybe you're right?

Quote:
Originally Posted by tromano

All things being equal a longer ski glides better because it has more wetted (lubricated) running length and is more streamlined compared to a shorter ski. There is a reason that XC skis are still 210 cm X 48mm wide.

Edited by Atomicman - 7/18/11 at 11:58am
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