# Contact length comparisons



## SnowDragon (Apr 23, 2012)

I'm wondering about comparing board length of two boards I have.

Rossignol Jibsaw 159 - running length 112
Lib Tech TRS Firepower 154 - contact length 115

Obviously the Jibsaw is the longer full length board.
But the running length/contact length measurements (same measurement, different name?) indicate to me that the TRS will feel like the longer board when riding it.

Are my assumptions correct, or am I missing something?
I plan to take both boards with me on Wednesday when I ride next.
I just want to ask if I am understanding the specs posted by the manufacturers.


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## poutanen (Dec 22, 2011)

I honestly think that running length is a useless spec. How often do you run flat? And how does the length of base touching the snow affect your riding?

As soon as you've got any decent angle on the board, effective edge length is the more important measurement. Maybe running length affects powder performance? I've never used is as a measure of board performance.

Cheers


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## SnowDragon (Apr 23, 2012)

Yah, I've always preferred effective edge as a measurement spec over contact/running length myself, but not all manufacturers list it for their boards.

Is there a way I can measure EE myself?


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## poutanen (Dec 22, 2011)

Place the board on its side on a flat surface, measure the distance between the widest part of the tip, and widest part of the tail.

I could see running length making a difference if it's drastically different than another board (i.e. a full camber board vs a full rocker board). But then you'd already know that it was going to handle differently based on the base profile.



Just to muddy the waters a bit, I have two boards with nearly identical overall shapes. Very similar length (159/160) and effective edge (140/144). One board has an early rise nose/nose rocker, and the other is more camber dominant. The camber dominant board is stiffer.

First impression of both boards is that the one that's softer, has a little nose rocker, and a slightly shorter effective edge actually carves better. It's taken me several days to realize I was wrong. The stiffer, cambered board, with a longer effective edge can carve better.

The trouble is it takes more effort to keep it smooth. It wants to chatter through corners unless I'm super aggressive with my riding, really conscious about getting low over the board. And I'm very sore at the end of a day riding it.

The softer board on the other hand doesn't tend to chatter as much when pushed to the limit, I can ride a slightly more relaxed position, and I'm ultimately much less gassed at the end of the day. And it carves almost as well. I'd have to run them through a race course to see if the stiffer one is actually significantly better.


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## SnowDragon (Apr 23, 2012)

Awesome!
Thanks for the guidance.
I'll try it tonight.


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## snowman55 (Feb 17, 2012)

poutanen said:


> Place the board on its side on a flat surface, measure the distance between the widest part of the tip, and widest part of the tail.
> 
> I could see running length making a difference if it's drastically different than another board (i.e. a full camber board vs a full rocker board). But then you'd already know that it was going to handle differently based on the base profile.
> 
> ...



How about for stability when going fast? Let's say two board has same camber profile. Board one is 160 with EE of 116 and board two is 155 with EE of 120. 

Which would feel more stable? My guess would be the shorter board with longer EE. Is that correct?


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## chomps1211 (Mar 30, 2011)

Excellent,… (if still a bit confusing to me) discussion!!! Subscribed!!!

I have been pondering this exact issue myself of late. My new JJ Explorer is a 162, Cam/Rock profile (Early rise nose …mild camber between the contact points,) and it has a _*significantly*_ shorter EE than my 157 Proto CT. 

116 on the Jones compared to 125 for the Proto! :blink:

Last weeks 9 consecutive days of riding (...in Great to Awesome conditions.) allowed me get a much better feel for how the Jones handles and it is without a doubt the _far_ more stable of the two!! :grin:

I realize that this may end up being an Apples/Oranges comparison as the Jones is by far the stiffer of the two boards. Not to mention the profiles being quite different. Setback - slightly tapered, Directional twin for the JJ with the Proto being a true twin CrC. But I am still curious to learn more about how EE differences are likely to effect the overall ride.

And apologies, but just to muddy things up further? Here's yet _another_ confusing variable to add to the mix….. 
*Sidecut radius!!*  How'z this variable factor in along with EE to alter all those ride characteristics being discussed. :dunno: I do know larger #radius ,… Bigger turning radius,… and vise-versa! 

JJ Explorer: straight forward 7.9m. NS Proto: Vario 735
I found the Jones to be quite nimble and quick on steeper terrain and @ moderately higher speeds,.. But when slowing down approaching the lift lines or flat basing the cat tracks etc. The Proto responds & turns quicker and with _much_ less effort!

Hopefully someone smarter than myself can shed some light on this and compare & explain these variables without requiring the reader to have an advanced degree in calculus to understand!  :laugh:


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## SnowDragon (Apr 23, 2012)

LOL!
I intentionally kept sidecut radius out of the discussion because I figured I WOULD need an advanced mathematics/physics degree to understand it!

(But I AM curious...)


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## poutanen (Dec 22, 2011)

snowman55 said:


> How about for stability when going fast? Let's say two board has same camber profile. Board one is 160 with EE of 116 and board two is 155 with EE of 120.


My thoughts on stability: This is a combination of many factors. Camber profile, stiffness, materials, dampness, etc. Effective edge to me is a good indicator of edge hold only. I.e. a board with a longer effective edge, will likely have more edge hold on hardpack.



chomps1211 said:


> I realize that this may end up being an Apples/Oranges comparison as the Jones is by far the stiffer of the two boards. Not to mention the profiles being quite different. Setback - slightly tapered, Directional twin for the JJ with the Proto being a true twin CrC. But I am still curious to learn more about how EE differences are likely to effect the overall ride.


I think you'd find if you were carving at slow/moderate speeds on hardpack, that the NS has more overall edge grip than the Jones (based on the longer effective edge). But as soon as you start ramping up the speed, the Jones is longer, stiffer, more directional, with a base profile that lends itself to carving/stability better. And the longer sidecut radius will lend itself to high speed turn stability. See below.




chomps1211 said:


> And apologies, but just to muddy things up further? Here's yet _another_ confusing variable to add to the mix…..
> *Sidecut radius!!*  How'z this variable factor in along with EE to alter all those ride characteristics being discussed. :dunno: I do know larger #radius ,… Bigger turning radius,… and vise-versa!
> 
> JJ Explorer: straight forward 7.9m. NS Proto: Vario 735
> I found the Jones to be quite nimble and quick on steeper terrain and @ moderately higher speeds,.. But when slowing down approaching the lift lines or flat basing the cat tracks etc. The Proto responds & turns quicker and with _much_ less effort!


Sidecut Radius:

Is a measure of the radius of a circle that would be formed if you continued drawing a circle with your board as the guide.

Here's how it affects a turn. The graphic below shows what happens when you get your board on an edge. The more angulation you get on the board, the tighter the top and tail angle upwards into the corner.



















Where this comes into play with us is, a longer/more shallow sidecut means that you have to tilt the board on a higher angle, to get the same turn radius with the board bent out on the snow. That can make it feel sluggish to turn at low speed (as you experienced).

But at high speed, for the same overall turn radius, the board with the longer sidecut radius will be on a higher angle, with the boards edge at a higher angle to the snow, providing more grip/bite.

Now that I've wrote that, I don't think I explained it very well! Bottom line is a longer radius will be tougher to turn in tight spaces (as you need to get it on more of an angle to execute the same turn on the snow), but more stable at speed (because you need to get it on more of an angle to execute the same turn on the snow... )


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## Phedder (Sep 13, 2014)

@poutanen, I'd say you explained that perfectly. I read the thread on the bus up today and was going to try explain when I got back, but you covered exactly what I would have and then some! Crystal clear 

I used to always prefer a smaller (#) deeper sidecut for how tight I could turn at low/moderate speeds, just cruising around carving back and forth, getting locked onto the rail super easily. Now I've spent some time on a few stiffer boards with a larger shallower sidecut and I can absolutely appreciate the effect that has on the overall ride once you're at a decent speed. Different tools for different purposes I suppose. Of course you can bomb on a deep sidecut, but it'll always feel a little twitchy on edge and more likely to wash out because at the speeds you're going, you won't have enough edge hold due to a lower edge angle to make the carve the boards sidecut wants you to. At low speeds with a shallow sidecut it may feel cumbersome to steer on edge because for the edge angle you need to make the sharper turns, you may not have enough speed to actually balance yourself over the edge and board being inclined that much. 

^Now THAT'S how you poorly explain something...:embarrased1:


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## SGboarder (Jun 24, 2012)

chomps1211 said:


> Excellent,… (if still a bit confusing to me) discussion!!! Subscribed!!!
> 
> I have been pondering this exact issue myself of late. My new JJ Explorer is a 162, Cam/Rock profile (Early rise nose …mild camber between the contact points,) and it has a _*significantly*_ shorter EE than my 157 Proto CT.
> 
> *116 on the Jones* compared to 125 for the Proto! :blink:


No, 116 is the running length. The EE is closer to 120.


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## SnowDragon (Apr 23, 2012)

SGboarder said:


> No, 116 is the running length. The EE is closer to 120.


According to the Jones website, the running length on the 162 Explorer is 119.6.
I'm used to the EE being longer than the running length, so I'm not sure from where the 116 measurement comes.

My 162 Salomon Man's Board has a running length of 112 and an EE of 125 according to their website, so the 116 measurement on the Jones Explorer makes no sense to me.


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## SGboarder (Jun 24, 2012)

GreyDragon said:


> According to the Jones website, the running length on the 162 Explorer is 119.6.
> I'm used to the EE being longer than the running length, so I'm not sure from where the 116 measurement comes.
> 
> My 162 Salomon Man's Board has a running length of 112 and an EE of 125 according to their website, so the 116 measurement on the Jones Explorer makes no sense to me.


Not quite. What Jones calls running length appears to the effective edge (maybe the linear measurement of it). But a couple of years ago the website and catalogue showed the contact length - which was 116 for the 162 Explorer.
So the relative measurements make sense.


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## chomps1211 (Mar 30, 2011)

SGboarder said:


> No, 116 is the running length. The EE is closer to 120.


Where are you getting that? Posted stats I have all claim 116 for EE. They do not even mention running length. 

Not claiming the stats I have _can't_ be wrong.... just stating that I have those from multiple sources and none mention running length. Only EE. 

-edit-
Btw... my Explorer is the 2015/16 model. 

Besides.... how could running length be *shorter* than EE? Has that got something to do with the extended, early rise rocker in the nose? 

You're Gonna hafta show me da money on that one! :blink:


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## SGboarder (Jun 24, 2012)

chomps1211 said:


> Where are you getting that? Posted stats I have all claim 116 for EE. They do not even mention running length.
> 
> Not claiming the stats I have _can't_ be wrong.... just stating that I have those from multiple sources and none mention running length. Only EE.
> 
> ...


Running length is virtually always less than the EE (even than the linear measurement of EE) - as GreyDragon correctly noted. Why? Because the contact points are on the upturned part of the board (especially for RCR and for any rocker-dominant profiles - but even true for most 'regular' camber decks).

Sources for the data points:
- 119.6 is straight from the Jones web-site: https://www.jonessnowboards.com/gear/solids/explorer.html
- 116 was what Jones as running length in the 2015/16 dealer catalogue:
Jones - zuzupopo / Catalogues - zuzupopo


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## ItchEtrigR (Jan 1, 2012)

2016 Jones Explorer 162 has a nose length of 23.7 and a tail length of 21.7 as stated by the website

23.7 + 21.7 = 45.4

Overlength 162 - 45.4= 116.6 effective edge

What they mean by running length is beyond me but that 119.6 is a number that doesn't add up. Maybe the length of the true effective edge with taking into account the magnetraction? Basically how long the effective edge is before it's shaped?

Sent from my SM-N900 using Tapatalk


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## chomps1211 (Mar 30, 2011)

ItchEtrigR said:


> 2016 Jones Explorer 162 has a nose length of 23.7 and a tail length of 21.7 as stated by the website
> 
> 23.7 + 21.7 = 45.4
> 
> ...


Yeah,.. I'm still a little confused myself. The specs for the '17 model Explorer have to be somewhat different as they've added that "lifted" contact point, Spoon tech to that years model. The 2016 model I have doesn't feature that! 

:shrug: I always was a little "Dyslexic" when it comes to numbers & math! :blink: Don't get me wrong,… I can add, subtract, multiply and divide! But I have a tendency to flip & transpose numbers so that even now I will often make stupid, obvious mistakes with plain old _basic_ math that I just don't see! Not until _after_ I've made myself look like a complete "Tard" anyways!!!! :laugh:  Happens to me No matter how often I double check my numbers or proofread. _(...Algebra gave me absolute *fits* trying to understand!!!)_

What I'm saying here is,.. You'll have to cut me a little slack if I'm missing something that's obvious to everyone else, cuz I'm DEFINITELY no "Rocket Surgeon" when it comes to numbers!!  :laugh:


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## ItchEtrigR (Jan 1, 2012)

chomps1211 said:


> Yeah,.. I'm still a little confused myself. The specs for the '17 model Explorer have to be somewhat different as they've added that "lifted" contact point, Spoon tech to that years model. The 2016 model I have doesn't feature that!
> 
> :shrug: I always was a little "Dyslexic" when it comes to numbers & math! :blink: Don't get me wrong,… I can add, subtract, multiply and divide! But I have a tendency to flip & transpose numbers so that even now I will often make stupid, obvious mistakes with plain old _basic_ math that I just don't see! Not until _after_ I've made myself look like a complete "Tard" anyways!!!!   Happens to me No matter how often I double check my numbers or proofread. _(...Algebra gave me absolute *fits* trying to understand!!!)_
> 
> What I'm saying here is,.. You'll have to cut me a little slack if I'm missing something that's obvious to everyone else, cuz I'm DEFINITELY no "Rocket Surgeon" when it comes to numbers!!


Basically your dead on with your first assumption of it being 116 its the websites tech details that doesn't fully explain what that figure represents. 

You can always grab a ruler and go to work if in doubt, but that number looks right to me considering thst their tip and tail length is indeed accurate.

Sent from my SM-N900 using Tapatalk


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## wrathfuldeity (Oct 5, 2007)

presuming groomer blasting...the down low...is you want longer edge contact and shallower radius if u are going fast (say 50+mph) for the feeling of stability and locked in cruise missle. If ur humping around...under 40mph then shorter edge contact and deeper radius for hot rodding around for ground to air or air to air blasting.


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## chomps1211 (Mar 30, 2011)

wrathfuldeity said:


> presuming groomer blasting...the down low...is you want longer edge contact and shallower radius if u are going fast (say 50+mph) for the feeling of stability and locked in cruise missle. If ur humping around...under 40mph then shorter edge contact and deeper radius for hot rodding around for ground to air or air to air blasting.


Ok... that makes sense to me. I already knew longer EE tended to = better edge hold & stability. 

I was just talking to someone else who explained the difference between EE & RL in a way that cleareed it up perfectly for me. (...it also expanded on Pouts diagram of what's going in when tilting the edge!)

This is how it was explained to me...

"EE is the length between widest point of the edge. (...essentially contact pount to contact point.).

*Running length is the length of the base touching snow.* For the Jones, since it has rockered nose, the EE is longer than RL. On a pure camber, both are +/- the same.

Put the Jones on a the floor. Kneel beside it an look from the side. You will see how much the base is touching the floor: That's where the measurements are done for running length.

Now,.. tilt it until its perpendicular on one edge to the floor. See how the length of the points where the edge touches the floor increases the more you tilt it? As soon as the widest points touch the ground, you're at the EE width."

That explanation along with Wraths & Pouts makes things a *lot* clearer for me! Hope it helps GD & others also! :grin:

-edit-
...oh! And I was mistaken about the Explorer being slightly tapered. Tip & tail are the same width. It's a directional twin because of the slightly setback stance. My Bad!!


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## poutanen (Dec 22, 2011)

chomps1211 said:


> You'll have to cut me a little slack if I'm missing something that's obvious to everyone else, cuz I'm DEFINITELY no "Rocket Surgeon" when it comes to numbers!!  :laugh:


The main thing is, don't get too caught up in the numbers. A 160 cm board with a slightly shorter effective edge than another 160 cm board, may still tend to carve better for most people, depending on the construction, sidecut radius, etc.

The numbers are only an indicator of roughly what the board *should* do. Just like sizing boots to feet, really the best way to tell is to try the board on... :grin:

For what it's worth, race boards generally run about 11-20m sidecut radius, with the higher numbers being used for more GS type events. And they've got huge effective edge... like 160 cm of EE for a typical 180 cm board.


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## chomps1211 (Mar 30, 2011)

poutanen said:


> The main thing is, don't get too caught up in the numbers. A 160 cm board with a slightly shorter effective edge than another 160 cm board, may still tend to carve better for most people, depending on the construction, sidecut radius, etc.
> 
> *The numbers are only an indicator of roughly what the board *should* do*. Just like sizing boots to feet, really the best way to tell is to try the board on... :grin:


Absolutely. And that's where it gets confusing for some of us,.. especially if we're a little fuzzy about what exactly some of the nomenclature or spec numbers are referring to. 

Prior to reading & researching this thread,.. I would have thought EE & RL were referring to roughly the same thing. Now I know better! >

Thanks to all who helped explain things in a simpler, less tech jargon manner.


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## SGboarder (Jun 24, 2012)

chomps1211 said:


> "EE is the length between widest point of the edge. (...essentially contact pount to contact point.).


Yes.



chomps1211 said:


> *Running length is the length of the base touching snow.* For the Jones, since it has rockered nose, the EE is longer than RL.





chomps1211 said:


> On a pure camber, both are +/- the same.


No. As I had explained even on pure camber boards the contact points are generally on the upturned part of the board/lifted of the ground. In addition (but less important) EE should properly measured along the curve of the edge (and hence be slightly longer than the corresponding straight line measurement).



chomps1211 said:


> Put the Jones on a the floor. Kneel beside it an look from the side. You will see how much the base is touching the floor: That's where the measurements are done for running length.
> 
> Now,.. tilt it until its perpendicular on one edge to the floor. See how the length of the points where the edge touches the floor increases the more you tilt it? As soon as the widest points touch the ground, you're at the EE width."


Pretty much that - and these are some of the most basic elements of snowboard design/shaping and has been discussed/explained many many times on this forum.
http://www.snowboardingforum.com/boards/166945-effective-edge.html
http://www.snowboardingforum.com/bo...h-vs-effective-edge-length-2.html#post1676785
http://www.snowboardingforum.com/boards/40915-contact-length-vs-effective-edge.html


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