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| Q&A: Slalom Pro Mike Maysey (2489 Posts)
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David e
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On 1/30/2003 TK
wrote in from
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I don't know much, but that was one bad ass post. Tons of insight. Thanks, TK
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?
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On 1/30/2003 Brady
wrote in from
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I`m just barely grasping what is said here so i`ll keep my question as simple as possible...
It seems that most riders use a differant truck set-up from the front to rear. Either a RTX with TTC or Indy 101 with offset. Or maybe an Indy and Seismic.
If the flex is affecting the turnyness of a truck, how will it affect trucks of varying turnyness thenselves? Generally it`s a faster turning truck up front. So will the flex increase the response or effect of the varying trucks or decrease it?
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thanks for the corrections
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On 1/30/2003
john airey
wrote in from
(63.113.nnn.nnn)
Mike, I get adam's nipple, er, point. when a flat
deck is flexed, even tho the distance from bolt to
bolt on the deck gets shorter, the distance from
axle to axle could get longer if the trucks are
tall. But I think the camber vs. flat argument regarding
cancelling and adding turning effects still
holds since adam's point applies to both board styles.
thank you mr. gordon for your correction about
decrease not increase on turning radius. I damaged
a decent camber vs flat summary by typing the wrong word.
Sadly, SF surf season is winding down Mike,
fall and winter giveth, but spring taketh.
you may have to drive your new hot
rod south if you are itching to get wet! call if
you want dispatch service... there are almost
always working spots. trick is finding the one with
less people and good waves. not always possible.
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Pop
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On 1/30/2003 Farid
wrote in from
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Since we are using suspension as a comparison, we should use the proper terminology.
"Pop" is rebound.
"Damped" is how the rebound (or comprssion) is controlled.
So a board that has no "damping" has a fast rebound or "pop".
A board that does not rebound fast is "damped" or worn out.
In suspension, they damp the shock absorbers so it does not rebound so fast that it might lift the wheel. They also use damp the shock on compression so it does not bottom out.
So, that might be where the next technological breakthrough might be - the ability to damp the comprssion and rebound of the board according to one's weight and the course layout.
Mike, you probably dial all this in w/ your mountain bike shock.
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flat vs. cambered decks
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On 1/30/2003 david e
wrote in from
(63.74.nnn.nnn)
From my experience, giving a deck "camber", or some camber-height, can create a fulcrum-effect over the relative amount of flex inherent in the materials alone. It sort of like a "pre-loading" that causes a cambered board to have a more progressive, stiffer-flex as it is down-weighted in the turn (as opposed to a non-cambered -flat board) Hence the more dramatic "pop" as the cambered board returns to its original shape coming out of the turn. This effect is either maximized or minimized depending on how much downward force a rider puts into the deck (and how much the flex resists this force, i.e.how well the flex matches the ability and weight of the rider). So the “deeper” a cambered board is flexed, the more it resists and the more energy it returns. Another factor is the resistance to twisting, or the torsional-rigidity RELATIVE to the amount of longitudinal flex. The great advancement in ski-technology over the past 20yrs is in this area ; you can now buy a relatively soft, round -flexing ski with a MUCH higher degree of torsional-rigidity than ever before, this results in greater edge pressure at the tip and tail from a shorter ski (hence Bode Miller’s, and all FIS World Cup slalom skiers are now on a lot shorter, softer skis than ever, while going faster). Also, you can now get a better “all-rounder” that works in deep pow and still hold an edge on ice. HG's "cap" technolgy references is this same concept. The similarity to skiing / snowboarding ends with one word, however; trucks. They complicate things!
Both flat and cambered decks have an overall lengthening WB, as well as, a general decrease in king-pin angle through the apex of turn, however this effect is off-set to a degree by the fact the wheels on the inside of the turn are now closer together (shortening wb) and the outside wheels are getting further apart, to the degree that the flex / camber allows. The angles through which the king-pin changes during the turn-sequence will vary according to a number of factors; including torsional –rigidity. One main factor is whether the deck is flat vs. cambered. In this case, the cambered deck can maintain a steeper king- pin angle through the turn, allowing a more sudden change in(tightening) the turn radius to make a cone. As mentioned, the cambered deck should be resisting the turn more,then suddenly release a burst of speed, while the turning response on the flat deck will maintain constant velocity, lending to greater stability and smother re-initiation.
My feeling is that a flat or slightly concave, non-cambered deck (i.e. Ick-stick Carrera) excels on a faster GS course where the wide off-sets turns are more carved than pumped and the cambered deck will excel where a high degree of acceleration is possible from a quick downward pumping force (i.e. flatter terrain. Again, this all depends on the boards flex being correctly matched to the riders weight and ability. The flat-decks might be easier for beginners since they are closer to the shape of the turn from the get-go. The camber-deck has to be first compressed to neutral and even heavy riders (as JG points out below) sometimes do not generate the downward force enough to get beyond neutral, relying on the trucks do the work from there.JMHO.
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Axles from Decks
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On 1/30/2003
Mike Maysey
wrote in from
(66.236.nnn.nnn)
The distance from the deck to the axle remains constant. Unless you use very spongy riser pads.
If I take a piece of paper and bend it up in the middle to create 'camber' with my fingers at either end, when I move my hands apart the 'camber' goes down or gets shallower. If I imagine my fingers are trucks, the trucks are getting further apart.
If you hold the same paper flat and push my hands together, the paper either bends up or bends down creating 'camber' or 'rocker.' Again, if I imagine my hands are trucks...they are getting closer together.
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girls on trampolines
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On 1/30/2003
Adam Corollla
wrote in from
(68.160.nnn.nnn)
The further the axles are away from the flexing deck the further the axles will "move apart" when the board is flexed for the same flex- even on a flat deck. The further axles are away from the deck the further apart the axles would move for the same flex. Wheelbase is the distance between the two axles.
Now for the less bland explanation-
The larger the cup size for a given woman jumping on a trampoline the further her nipple is from her chest- for a breast of the same firmness (Angelina Jolie vs Wynona Ryder) the larger breasts nipple Ie. the "whee!base" moves. Several hours of slow motion replay might be required at the end of "The Man Show" to determine this.
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geometry
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On 1/30/2003
hg
wrote in from
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John A -
2b. flat - the flex which makes the trucks more "turny" will decrease the turning radius. Agreed that the effects do add.
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camber and wheelbase
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On 1/30/2003
Mike Maysey
wrote in from
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Thanks John A. That makes sense and reads very quickly. Hey John, where's the good surf gonna be this weekend?
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camber and wheelbase
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On 1/30/2003
john airey
wrote in from
(63.113.nnn.nnn)
mike, here's my own summary so far
(I got an "A" in geometry once, possibly twice):
1. concave (not camber) can stiffen a deck. (more pop, :-)).
2.A. camber: wheelbase gets longer as board flattens through
turn and trucks get wedged (more turny).
these two effects can cancel each other so turning radius can stay more nearly constant.
2.B flat: wheelbase gets shorter as board flexes through
a turn and trucks get wedged (more turny).
these two effects can add so turning radius will
increase through the turn.
3. flex 'period' is perhaps more important than flex
'amplitude'. short flex period is good for turns that take less time. longer flex period is good for turns
that take more time. usually flex period and flex amount
do go together but not always. some materials flex faster
than others.
5. derivative of flex. save this for 2004.
---
comments:
mike, a board with too long of a flex period will hold
you back. I think this matters more than how much it
actually flexes. If your TS board flexes more but flexes
faster (faster period) you are okay with it. the flex
time just has to match your turning speed. if it is
rebounding in time to make the next cone keep riding it.
you can correct my summary as needed.
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Progressiveness of Flex
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On 1/30/2003
Mike Maysey
wrote in from
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Hey John,
Wow, that's quite a lot to try and absorb. Please do tell us about the progressiveness of flex. I think I've felt it before, but I'm not sure. Is this the feeling that you are overpumping the board? Like when you really jam on it, it's just not there? Or is this something more along the lines of a progressuve shock absorber? It starts out easy and gets progressively harder. I have shocks on my mountain bike like that. Well, I abjusted them that way so they'd take up all the little bumps and stuff in the road and would still come to play when there was a big rock, stump or some other big object in the trail and not bottom out. This is interesting...I can think of different boards I've ridden in my SHORT stint in slalom and the ones I rode that we less progressive we always very flexy boards...and the ones with more progressive have been stiffer. Am I totally off base? Do board builders even take into consideration the progressiveness of flex? Is it something worth considering? I think so, what do you think? Opinions...
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More techno drivel
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On 1/30/2003
John Gilmour
wrote in from
(68.160.nnn.nnn)
Wesley, yes Tod (TOD is the correct spelling as it is really his initials Theodore Otto Drescher but for everyones health don't call him Theodore) Drescher has ridden my fullnose a lot- and true to what you are saying- the board for my weight is pretty stiff- though I do flex it when ridden hard. When TOD rides it he does not flex the board as much because he isn't generating downforce. (He really doesn't have to to get much traction as he weighs so much he is readily deforming the traction patch on his urethane wheels-flattening them as he rides- getting more grip than the rest of do at his 250 lbs.)
"Note that with a non-cambered board, the downforce through the curve will shorten the wheelbase, which effectively generates a decelerating force."
Well with a flat deck if you actually measure the distance from axle to axle you may find that the wheelbase actually elongates when flexed. And the downforce allows you to drive the board harder latterally to acellerate.
There are a few things going on in regards to flex.
Firstly in regards to the road we have several different kinds of things going on- in regards to flex in the system and maintaining the "correct suspension" ie road contact.
1. We have to absorb the larger surface imperfections in the road (cracks bumps etc.)
2. We must maintain contact with the road surface despite the surface abnormalities on the near micro scale.
3. We must adjust our suspension for differing g-forces through the turn and the effects on turning.
SO for "1" our "macro" suspension is our legs and we endeveor to absorb cracks in the pavement by "deweighting our decks". Since we don't have true shock absorbers and Independent suspension we must deweight the entire deck (not so good a way to deal with it) it would be like comparing how a regular car handles potholes and how a guy in a "hopping lowrider" might try to "pre hop" a pot hole ever so slightly to not bottom out his low ride.
Number "2" handles the courseness or "pebbleyness" of the road. This is optimized through durometer choice- and the thickness of the supported and unsupported uerthane on the wheel. Obviously the ground is not as smooth as glass so our traction patch is reduced. We want enough deformation into the surface to increase our traction patch, but not enough to mush in front of the wheel (Ie pushing a wavefront that is optimally too large relative to the diameter of the wheel) Such a overly deforming wheel would be slow. Go too hard in the wheel or too little supported and unsupported uerthane and you are only riding the "peaks of the pebbles" and with such a small contact patch you can "wax out" during a turn. Not to mention it is a hard ride.
Obviously the more level the asphalt is- the harder a durometer you can run- except to the point of running too hard a wheel which "deforms the pavement on a hot day" and pushes a "pavement wavefront" (yes its on a very micro scale- but sinec pavement is so much more viscous it doesn't take much of a wave height ot have a similar effect)in front of the wheel - also bad and slow.
In "3" we see how the cornering affects grip of the system. in a hard corner we exert more lateral force on the ground and urethane. In a ZERO flex deck the ability to "dole out" a smooth progressive increase in pressure that is perfect in regards to the arc of a turn is limited by the prowess of the rider. And for the harder and faster the run the harder it is to "modulate" the amount of force needed.
Most riders opt for having the FLEX deck do this by loading the deck and having the deck "remodulate" the force to the pavement. Also the deck may be able to assist in "remodulating" the force better than the rider can. For instance....we could all throw a spear, and certainly we could throw a spear the size of an arrow- but using a flexing bow helps to convert one aspect of our fitness into another. Ie we are converting Strength into Quickness- using the flexing bow for conversion.
How the bow accelerates the force is a function of the design of the bow/flexing skateboard and the duration of the speed is the "pop- period" of the deck. The shorter the "pop-period" the better the deck is suited to short turns of fewer degrees at high fequency (TS). The longer the "pop-Period" of the deck the better the deck is suited for drawn out turns that take a while to complete (GS).
Strangley enough....when the turns are very long and wide and drawn out- though small in degrees- we have a turn that is "Slow" enough in terms of building g-forces to react using our body. Such an example would be akin to using a servo controlled subwoofer because the waves are at a low enough frequency for a slow servo to be considered "fast acting" for such a system. Our legs can react fast enough at long drawn out turns in Super G and so long travel flex can become uneeded in these situations- especially where the deck could hit a resonant fequency. (look at how the rider lowers himself in a super g turn and how bent his legs are- he is "human suspension" and pavement changes in terms of very elongated waves are treatable using this riding style- extreme flex would be more a detriment than a help)
Lastly in "3" the wheelbase ELONGATES during high flex- the center of gravity LOWERS and the turning geometry of the trucks INCREASES. Hmmm sounds like we are making any deck more into a GS deck ie longer wheelbase, slightly increased turning geometry for both trucks, and lower camber. And indeed this is what happens.
We are making our board more suited for the longer turn by altering the boards characteristics while riding it- simultaneously increasing our traction by deforming the wheel with downforce (as opposed to overwhelming the wheel with lateral force)and by loading the wheel first in the downward direction we are taking up some of the slop which might otherwise be used to overwhelm the wheel in the lateral direction.
The shortest distance between two points is....a straight line.
So in hitting the apex of the turn in a widely offset course - at slow speeds-sub 15mph (otherwise the wheels might be overwhelmed latterally) a board with significant flex and high camber would allow the turning arc to get much tighter resulting in a "Z" turn (note the shape of the letter Z) with increased steering "around the cones" and straighter steering "between the cones". Such a deck was ridden by Marus Stroble in Morro Bay 2001.
Add a lot of speed and the "Z" turn becomes useless (lateral forces build too quickly due to lateral g's which overwhelm the system) and a different line and board truck type should be used.
So board flex is part suspension, part truck geometry. The flex should match the rider's weight for the intended course and the riders ability to drive into the deck.
And of course we haven't touched on how important the first derivitave of flex ie the acceleration or progressiveness of the flex is.
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concave
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On 1/29/2003
hg
wrote in from
(208.14.nnn.nnn)
Any amount of concavity along the longitudinal axis of the deck is going to reduce flex. You can see that if you take a piece of notebook paper and prop it up like a Quonset hut, and you'll see that it really doesn't want to bend along the main axis. If you look at cap construction in rolled rail decks, you'll see this stiffening phenomenon on a smaller scale.
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camber
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On 1/29/2003 Brady
wrote in from
(66.21.nnn.nnn)
I should probably go lurk with Dr P as my last post didn`t really say much. I just wanted to add the complexity of concave with camber and how it relates to flex in this bit.
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Why do we wedge?
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On 1/29/2003
Mike Maysey
wrote in from
(66.236.nnn.nnn)
So the wedges play a role in tuning and detuning trucks? The amount of wedging then will probably be based on how much camber a board has. So you wouldn't use the same wedge on a 1.5" camber board and a .75" camber board...or would you...things that make you go, hmmmmmmmm.
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Dr. P
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On 1/29/2003
Mike Maysey
wrote in from
(66.236.nnn.nnn)
That's Sergent to you, soldier. heh
Isn't learning fun?
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37yr old freshman
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On 1/29/2003 Dr P
wrote in from
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No sir, I just here to learn. Sir.
(...back to lurking.)
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Camber...
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On 1/29/2003
Mike Maysey
wrote in from
(66.236.nnn.nnn)
Dr P,
Are you making fun of us who 'know it all?'
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Camber
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On 1/29/2003
Dr P
wrote in from
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Ahem, I don't really feel qualified to step up and speak in a room with such dignitaries but...
I would think that the purpose of camber would be to keep the "travel" of the board's flex centered around Neutral or flat. Standing on the board will (should?) bring the camber close to neutral. Weighting and unweighting would dynamicaly wedge/de-wedge the trucks geometry with respect to neutral.
My (and I guess Gareth's) question would be: Since we often alter the truck' geometry anyway, is wedging/dewedging of a balanced camber preferable to the wedging/more-wedging obtained by flexing a flat or rocker board?
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What about concave?
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On 1/29/2003
Brady
wrote in from
(66.21.nnn.nnn)
The only deck I have that sports concave is my Pumpkin but I heard some Comets do as well as Icks. On my Pumpkin, the concave is 3/4" but rolls across the whole deck rather than at the edges on a newschool deck.
Everyone including me assumed the concave would eliminate the camber (1 1/4") but it doesn`t.
Now as GBJ was talking about snap and buck of the camber, memories of the black and green Turner Needkenose I used to have and it`s tendency ro get away from me on the snap...arrrghhhh!!!
My Turner popped. My Roe Hester snaps, and my Pumpkin just absorbs bumps in the road.
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slalom board camber
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On 1/29/2003
hg
wrote in from
(208.14.nnn.nnn)
The boards are cambered to create an accelerating pop when the rider generates a downforce in a turn.
When moving straight, flexing the board through it's camber as no real effect, as the wheelbase is lengthened and shortened on the line in which the board is moving.
When moving through a curve, the downforce on a cambered board changes the radius of the curve on which the board is moving, effectly creating a push or force by the rear wheels against that curve. This will generate some acceleration. Ideally, the downward motion occurs during the turn and the upward return of the board occurs when the path has straightened.
Note that with a non-cambered board, the downforce through the curve will shorten the wheelbase, which effectively generates a decelerating force. A non-cambered board would make sense for courses where braking is desired (e.g. downhill). That's why some riders find that a flipped cambered downhill board works better than an unflipped board.
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Corrections from an Uncommon Man
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On 1/29/2003
Wesley Tucker
wrote in from
(152.163.nnn.nnn)
Last sentence, second paragraph reads, "Well, it probably hasn't, it's just that the rider his pumping A LOT harder and making the board feels more mushy."
That should say, "Well, it probably hasn't, it's just that the rider IS pumping A LOT harder and making the board FEEL more mushy."
Everybody needs a good copyeditor!
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Flex for the Common Man
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On 1/29/2003
Wesley Tucker
wrote in from
(152.163.nnn.nnn)
Well, Mike, since you asked . . . :-)
As I mentioned before regarding John Hutson, another factor that cannot be trivialized is STRENGTH. As some one skates more, gets in better condition and rides with more authority, the rider may also consider adjusting his flex/camber requirements.
Let's put it this way: Gilmour can pump so hard he bends truck axles. Now, if someone starts skating today on a new cambered medium flex board, is it possible that board will have the same performance a year from now when the skater drops 20 pounds, reduces his BMI and raised his overall muscle? The board won't change, but the rider will feel like his once-perfect "medium" flex has gone soft. Well, it probably hasn't, it's just that the rider his pumping A LOT harder and making the board feels more mushy.
Again, this is a matter of personal preference. Let's say, though, for example a guy who skates two hours a day for 10 years weighs 170 pounds and another guy who started slaloming last week also weighs 170 pounds. They both decide on a "medium" flex. Well, Gareth builds one for both of them rated for 170 pounds. Guess what? The newbie probably thinks it's too hard and the veteran will wonder what Gareth was thinking shipping him a box full of mush.
How do we rectify and adjust this quandary? Simple: we skate and skate A LOT. There's no substitute for just doing it getting a feel for what works best FOR YOU. So, the veteran has learned a hard lesson: next time, tell Gareth he really weighs 185. Maybe getting a "medium" flex board for someone who weighs 15 pounds more might feel "just right" for the guy who's ripped and ready.
And the newbie? Well, when he calls Seattle to complain, Gareth just tells him in the most soothing voice he can muster, "trust me, my friend, you'll grow into it!"
That's about the best anyone can expect.
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Flex/Camber
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On 1/29/2003
Hamm
wrote in from
(63.175.nnn.nnn)
Mike, correct me if I'm wrong, but I think you answered:
Why do slalom decks flex?
and not
Why do slalom boards have camber?
Pocket Pistols TS decks have more camber than the HS & GS decks similar to the ICKs
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flex...
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On 1/29/2003 psYch0Lloyd
wrote in from
(198.160.nnn.nnn)
...pattern
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