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Roller Derby Forum Discussions about banked-track and flat-track roller derby events, teams, skaters, and training methods.

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Old August 7th, 2015, 08:54 AM   #1
marlowebeach
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Default 78 not sticky enough?

Fifth season in derby, primarily jam. 130 pounds, currently skating Bont Hybrid Carbon/Venus. We just went to uncoated polished concrete from sport court, and I'm having trouble staying upright. I was relatively fast and happy on the sport court on either 94 Ikons or 95 Zombies.

First I went to Poisons. Then 4 Poison, 4 of my old Ghosts (slim 80s). I still can't get to a full sprint. Borrowed someone's outdoor Kryptos (78). A little better but I'm still sliding several feet in every turn and not even at full speed. I have good form (I've been told) and I'm consciously focusing on full 8 wheel contact on every step, but is there anything more I can do? Are there softer wheels that would fit my plate? I already skate with loose trucks, and I switched to softer cushions.

Everyone under ~150 pounds is having similar problems, but I want to solve it, dammit.
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Old August 7th, 2015, 10:56 AM   #2
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89 to 93 A 30mm wide 62mm tall. Find something around there. Vanilla groove n glide is that size with varing hardnesses. Not tue best out there but the profine is right.

Wide wheels dont do well on slippery floors. Go harder , go narrow as all get out.

Also, softer wheels have a lot more deflection in them, so each rotation will cause more lateral deflection than a harder wheel.
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Old August 7th, 2015, 02:57 PM   #3
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Never been on sport court, but it's my understanding that it's soft, so I think a little bit of time to adapt to a harder surface might be in order, if the krypton didn't hook up,, that's problematic, they are very sticky, no mention of your location, but if yer down under, is it possible the krypton are counterfeit, and possibly a plastic instead of their soft grippy urethane.

I'm an outdoor skater, on cement with a sandpaper type surface, no slip whatsoever, unless it's wet.

I'm thinking that all ya all are so used to inhuman effort to skate the sport court you all will have to adapt to a harder surface??

Anyway, I use the roll-line helium wheels, really like them, absolute grip, I have krypton and prefer the helium.

Thinking of slicks on a drag car, the wider the more grip...the thinner the more slide
Unfortunately this forum seems to be under the spell of intelligent design, you have to think for yourself or its easy to take advice that's contrary to reality
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Old August 7th, 2015, 03:43 PM   #4
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Never been on sport court, but it's my understanding that it's soft, so I think a little bit of time to adapt to a harder surface might be in order, if the krypton didn't hook up,, that's problematic, they are very sticky, no mention of your location, but if yer down under, is it possible the krypton are counterfeit, and possibly a plastic instead of their soft grippy urethane.

I'm an outdoor skater, on cement with a sandpaper type surface, no slip whatsoever, unless it's wet.

I'm thinking that all ya all are so used to inhuman effort to skate the sport court you all will have to adapt to a harder surface??

Anyway, I use the roll-line helium wheels, really like them, absolute grip, I have krypton and prefer the helium.

Thinking of slicks on a drag car, the wider the more grip...the thinner the more slide

Unfortunately this forum seems to be under the spell of intelligent design, you have to think for yourself or its easy to take advice that's contrary to reality
This is not necessarily true. I have skated many wheels on many different surfaces. Wide wheels will not always increase traction. In many situations they decrease it.

I recently went to Lexington Kentucky, where I practiced with their mens derby team. The floor was polished concrete. I started on 98A Zombie MID's(62x38)didnt have a whole lot of grip l, so I changed to 89A Zombie MAX's(62x44) The grip was almost identical. So what is going on here? Pressure. Theres a large difference in the PSI between a wide and narrow wheel. A narrow wheel will ultimately have greater PSI on it than the wider wheel.

Comparing dragsters to skates is not a good comparison at all.


Not convinced? Look at inlines. How much wheel width is actually in contact with a skating surface? How much more grip inlines have than quad skates.. its ridiculous.

Whats more is I wanted to really test this out, vanilla is or was having a sale on their wheels that I took advantage of. I bought 3 sets of wheels. All the same durometer, 99A. Here are the sizes.

Vanilla Deluxe 62 x 42 99A
Vanilla Groove (n glides )62 x 30 99A
Vanilla Royals 57 x 30 99A

The wide wheels by far, are slippery as hell. They do not grip. Unless i go up on the front axles only, the PSI is not enough to make them stick to the floor. The narrow 62x30 set is VERY grippy. There is a lot more available pressure. Even my friend who weighs 155 compared to my 185, him having cranked down 10 deg action with 85A cushions vs my 45 deg action (arius plates ) when he wore the narrows and I wore the wides, there was no chance in holding the floor as well as he did. We switched wheels, same effect. He couldn't hold the floor. We tried a third friend with those 2 sets each. Same results. The narrow wheel won. As for the heights, the difference between the 2 30mm wide wheels, well the smaller diameter wheeel was lighter, and a bit more touchy. Meaning there was virtually the same grip, however it would break loose much easier, and stay loose (sliding/vibrating)The reason being is that the urethane is like a shock absorber.

Not only that but narrow wheels are faster than a wider wheel. They do have a bit less stability. .. as in they are more tippy..., but I will say that when I did a hockey stop on both, the wide wheel was so sljppery I fell the first time trying to stop to pick up some trash on our rink floor.

This isn't a tennis court ursle.
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Old August 7th, 2015, 10:30 PM   #5
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Hmm. So either increase the contact patch even more, but I think the only way to do that beyond the Kryptos is to go to a set of skateboard wheels (with sideset hubs) or go the other direction to a harder, slimmer profile and see if I can get enough force down that way. The only wheel I have of that type is a set of Atom Strokers but I think a 98a is going to be too much on the concrete surface at this weight no matter what -- I have them for sticky rinks and that rubberized floor stuff, and I like them a lot for that, but...

Maybe I'll see what's available locally this afternoon. I have to scrimmage on this tomorrow, and we're all predicting very low scoring.

I'm in the US, the Kryptos are definitely real, from a well-known shop.

So a big but slim wheel in the 90ish range as my next round. Onward and sideways!
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Old August 8th, 2015, 03:42 AM   #6
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I have good form (I've been told) and I'm consciously focusing on full 8 wheel contact on every step, but is there anything more I can do?
You can change your technique. There are different adaptations for slick and sticky floors. The first thing you can do is take shorter strides and keep your feet moving. As the foot gets further out from under your center of gravity it has less force on the ground which means less friction. By not extending as far you lose the part of the stride which wasn't as laden with friction. If you can get one more cross in per corner this way without giving up the rest of your form you can keep some decent speed. Also try to keep your feet moving a little bit more. It's counterintuitive, but you don't tend to feel your feet slipping as much when they are moving because your brain is programmed to think they should be moving. Of course, your balance isn't quite as good as when you hold a position, which is where the shortened strides come back in. You never extend so far beyond your center of balance that you can't adapt to slipping in the moving feet.

I don't know how it translates to derby, but if you just want pure speed you can also adjust your track. When you slide you slow down. You can just admit to yourself that it is inevitable on this track and force the slide where it will do you the most good - right at the entrance to the corner. You're going to slow down anyway, so do it right before you have an entire corner of powerful strokes to make up the speed. That also means you reach full speed in the straightaway, where there is no danger of sliding and slowing down. This is an exhausting way to skate because you are slowing down and speeding up every corner, but on some floor conditions it is the fastest pattern. Go into the corner harder than usual. This can be accomplished by either leaning in more than usual, cutting in early and taking it sharp, "sitting" right as you enter the corner, or some combination of the three. Slide until you reach the right speed, then start stepping. By stepping you transition from dynamic to static friction (I'll explain more if you really want), and if you chose the speed right your next step will stick. Then work really hard with proper form to make each step through the corner more powerful than the last. You accelerate halfway up the straightaway, then set up and repeat in the next corner.
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Old August 8th, 2015, 04:18 AM   #7
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No, not harder and slim or wide and soft.

The thing I was illustrating is that a narrower wheel for the same hardness will have more pressure ,and thus offer more grip. Additionally it will be faster than its softer wider counterpart.

I would suggest for your weight to get a 89 to 93 A with a very slim profile. Preferably aluminum hubs.

Vanilla groves at 62 x 30 in varying hardnesses would be a good choice or another wheel with the same height and width.

The only thing a softer wheel is going to do is stick a little better, and deflect to the side so it wont hold a tight turn.

Like i said before a 89 and 98 a wheel had almost identical grip. The harder wheel was narrow, and had grip because i had enougj pressure to make it stick. The wider wheel didnt make me any faster at all on the same floor.
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Old August 8th, 2015, 12:17 PM   #8
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Right, one of you said narrow and step back up in duro to the normal range from the 78; the other guy said go bigger and softer. One of these is more easily accomplished than the other, since softer than a 78 is kind of impossible. Although the local shop didn't have anything just right in stock on the slim side either so it'll have to wait a week or so. Also have a call out to my league to see if anyone's got a 90-93 62/30ish I can try.

Interesting, WJCIV. Some of this I've already done -- I cannot do my usual full extension crossovers at all, so the short quick steps are happening instead. As a derby skater/jammer I already try to skate the oval as a circle, cutting in hard across the apexes. I'm definitely getting lower than usual coming into those corners too. However, what's typically happening is that I start losing it about 2/3 of the way through the turn, when normally I'd be at max acceleration, and at that point I'm just trying to hang on and control the drift into the straightaway where I can start stepping again. I'm going to try what you're saying about pushing harder for speed on the straightaways and sliding *into* the turn instead of out of it.
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Old August 8th, 2015, 12:29 PM   #9
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If the wheel is really narrow then youd be suprised how hard it can be and still have good grip.

Trying to get some 30mm wide wheels is harder though if you got derby friends, most use wide wheels.

Ive tried over 14 sets of wheels on various floors ranging in grip from non existent to impossible to hockey stop, each time the wider the wheel the easier it was to slide... well when attempting to get more traction by using a wider wheel, on the floors that had intense grip I didnt have a harder and wider wheel with me to use. Thought I habe no doubt it would habe made hockey stopping possible.

Its really hard to learn to crossover continously if your grip is lacking
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Old August 8th, 2015, 05:24 PM   #10
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I'm definitely getting lower than usual coming into those corners too.
That's good, but not quite what I meant by sitting. If you start a little higher than usual then sit into skater position right at the entrance you apply more force to the ground because your center of mass is going faster into the corner without actually having to go faster. So it breaks your wheels free into a slide right at the entrance to the corner. It is a very subtle adjustment, and it takes some practice to do while still getting low enough in the corners and keeping your feet beneath you.

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As a derby skater/jammer I already try to skate the oval as a circle, cutting in hard across the apexes. ... However, what's typically happening is that I start losing it about 2/3 of the way through the turn, when normally I'd be at max acceleration, and at that point I'm just trying to hang on and control the drift into the straightaway where I can start stepping again.
Another way to think about this is to shift the apex earlier in the corner and flatten out the rest. The more you are turning the more you are prone to sliding. If you have a really sharp turn at the beginning the rest of the corner doesn't have to be as sharp as usual. Or you may try choosing a point about 1/3 of the way through your turn that you normally hit but entering the turn later so you have to turn sharper to hit it. That doesn't flatten out the rest of the corner, but it does scrub off a bit more speed on entry.

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I'm going to try what you're saying about pushing harder for speed on the straightaways and sliding *into* the turn instead of out of it.
Realize that the harder you push up the straightaway the more speed you scrub off on entry. I very rarely step more than half a step past the finish line. Even on most slick floors halfway up the straightaway is good enough. It's a very inefficient way of skating, so you will wear out. Also you want to step with crosses the whole track; don't get into the side-to-side stride. The steps will be directed more backwards than usual because straightaways are straight. This can be done by kicking a little more back (the trucks will do some of it for you) or by ajdusting which way you turn your body.
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Old August 14th, 2015, 03:59 AM   #11
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Default You missed one

You're all overlooking one very important aspect.

The action.

I doesn't matter what kind of wheel it is, hard, soft, wide, narrow, if the action of the trucks isn't right. If it's too stiff, when you try to turn, you'll lift a wheel and then all bets are off. That may be why a narrow wheel feels more grippy - takes more to lift.

You will certainly have to adjust your technique to adapt to different surfaces. Now adjust your trucks to adapt. If you use a looser, more compliant action, when you try to turn, the cushions will actually compress and allow the truck to move, which will keep the wheels in contact with the floor better and longer, and that means more grip. Go to a softer cushion and loosen it up. That will take a little getting used to, but its worth it. You will likely find that you can go back to a harder wheel once you train yourself to skate a looser action.
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Old August 14th, 2015, 08:11 AM   #12
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We've tried the same urethane on 4 different setus with varying degrees of action angle and suspension stiffness. No matter whatx the narrow wheel won hands down.

Action cant do jack if you dont have the grip in the first place.

My skate: Size 12 Arius 193mm wheelbase 80A cushions mounted to a Vanialla freestyle.
Daven's : Sg Century running 85A cushions cranked way down on a Vanilla Diamond walker
Tanner's : Reactor plate, with orange cushions, on a 395
Olivia's: size 3 mag avenger blue cushions set to light compression so standing causes no looseness. Mounted to a hybrid carbon.

Every skate performs better with narrow wheels as grip goes when only the contact patch changes.

Ultimately the softer suspension setups only really keep the skate from being as tippy on more narrow wheels. I dont find the grip that much better, but i never ran rock hard stuff anyways. Everything matters when looking at skates,
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Old August 14th, 2015, 04:55 PM   #13
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We've tried the same urethane on 4 different setus with varying degrees of action angle and suspension stiffness. No matter whatx the narrow wheel won hands down.
Are you certain that it's the same urethane? I don't mean same manufacturer or same durometer, I mean the same urethane.

Your observations are good data and are relevant, but by no means equate to universal truth. It means that's your experience with those wheels, on those skates with those skaters on that floor on that day. That's far too many variables to declare a conclusion.

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Action cant do jack if you dont have the grip in the first place.
You can easily reverse the argument. Your wheels can't do jack if your action doesn't support them.

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Every skate performs better with narrow wheels as grip goes when only the contact patch changes.
If that's so, then why did indoor quad speed adopt wheels in the 40mm width range (or wider)? You never even saw 38mm. Surely someone somewhere would have evaluated that.
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Old August 14th, 2015, 06:47 PM   #14
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Are you certain that it's the same urethane? I don't mean same manufacturer or same durometer, I mean the same urethane.

Its the same urethane, or as close as its going to get without being the exact same batch. The testing was significant enough to declare it as truth IMO.

Your observations are good data and are relevant, but by no means equate to universal truth. It means that's your experience with those wheels, on those skates with those skaters on that floor on that day. That's far too many variables to declare a conclusion.

i disagree. The variables were a vital part of this test, in each circumstance when a hard wheel was used, the narrow wheels produced a LOT more grip. This proves consistency across the board.

You can easily reverse the argument. Your wheels can't do jack if your action doesn't support them.

Wheels will do what they always do. They will have a set grip given the conditions at hand. The action of the skates will turn them. Action doesnt increase grip. It only uses the available grip. Also i think lower degree action skates can produce more grip than their higher action cousins. I wont explain why here though. But it more or less is a stability thing, also how the wheels kilter in. However its not a stability that a skater can make an adjustment for. Just think of a car, the harder you turn the less lateral foothold you have.



If that's so, then why did indoor quad speed adopt wheels in the 40mm width range (or wider)? You never even saw 38mm. Surely someone somewhere would have evaluated that.
People, by nature, are not analytical. Look at automotive racing, and how many worthless things have "caught on" or become "fact" when recently provenwrong by say mythbusters or other scientific studies and data. Just because something has evolved to its current state does not mean that it is whats best. There are a massive amount of misconceptions that more is better, such as wheel width.

A very tacky floor can be too much for a narrow wheel and you can have too much grip for some instances, so going with a slightly wider wheel may help. Think of trying to ride a touring bike on sand. Epic fail, switching to the obviously slower and wider wheel of a beach bike actually makes you faster and have better traction response for a given surface. Too thick of urethane coatings do the same thing.

Wheel selection for floors can vary to get the best results, but its not like people tend to think. Urethane is what people tend to look at as compatibility goes for floors, when its more like the profile of the wheel is the problem. Urethane just doesnt magically stop working when it hits certian floors, usually theres something else a user isn't noticing.
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Old August 14th, 2015, 07:37 PM   #15
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Mort, I don't doubt that you had better traction on the thinner wheels, but like dvw stated it's about the reduced leverage. If you look up the equation for the force of friction it is force applied * the coefficient of friction. Surface area does not appear. If you lessen the surface area you get more PSI, but you also get less contact. The two balance out. However, this assume that the force down is the same. As dvw pointed out the wider wheels have a greater mechanical advantage to torque the suspension, so the are more likely to come of the ground as you chatter around the turn. If the wheel is not in contact with the ground it offers no friction whatsoever. So thinner wheels may grip better for you, but not because of how you are explaining it. It may work for different people to different degrees depending on their technique and suspension.

Things tend to travel in a direction unless you apply a force. In order to apply a force in the turn your wheels have to be down. But there is an interesting thing about quads that you don't see on inlines. The ankles bend. In some sense the line of momentum is over the top of the wheels instead of down through them. That means if the wheels chatter off the ground your momentum "pushes" you toward the outside of the turn over top of the wheels, whereas inlines you tend to push your momentum through the wheels and actually gain traction if you keep your ankles straight and in line (I know this is a big simplification of the physics, but it's easier to visualize). It doesn't have to do with the width of the wheel on inlines unless you consider that narrow wheels are necessary to get the proper edge to get rid of the suspension to allow you to do this.

That said, the OP said the suspension is already loose on soft cushions. I took that at face value. For the given suspension thinner wheels might stick better. I've never experimented with wheel width, so I don't know.

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Think of trying to ride a touring bike on sand. Epic fail, switching to the obviously slower and wider wheel of a beach bike actually makes you faster and have better traction response for a given surface.
I'm not sure what you mean by this analogy. A wider tire spreads your force out so you don't sink into the sand. Kind of like how snow shows keep you on top of the snow instead of sinking in when just wearing boots. So you're faster because you don't take the effort to displace as much sand. I don't know why you would get greater traction unless you are also switching up the treads which allow greater side forces to be applied.
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Old August 15th, 2015, 02:20 AM   #16
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So you're faster because you don't take the effort to displace as much sand. I don't know why you would get greater traction unless you are also switching up the treads which allow greater side forces to be applied.
It's simple. This is a perfect example of why higher force in PSI is not your friend.

On the skinny tire, the weight of rider and bike are making contact with the sand with a very small contact area. High PSI. All of the forces related to keeping the bike on top of the sand, driving the rear wheel and steering are very high on that small contact patch, so that force wins, and the sand is disturbed.

On a wider tire, same rider and bike weight are spread out over a larger contact area. Lower PSI. The bike remains more in control because it isn't disturbing the sand as much, and the force is more balanced.

It's an old off-road driver's trick, especially rock climbers. Reduce the tire pressure so the tires are more compliant and there's a larger surface area to beard the load of the vehicle and the driving and steering forces.

Essentially the same principal as dragster tires. Big, wide, soft, low air pressure. Low PSI so that there's less vehicle weight and driving force per unit of contact. If hard, skinny tires were the secret sauce, they'd all run them. In fact they do - on the front where they don't want a lot of friction between the tire and the track.
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Old August 15th, 2015, 02:31 AM   #17
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Action doesnt increase grip. It only uses the available grip.
Your correct. But with all other factors static, a compliant action can make use of more of the available grip.

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Also i think lower degree action skates can produce more grip than their higher action cousins. I wont explain why here though.
That's a shame, because I'd like to know the basis for your conclusion.

I've been fortunate enough to skate on a very wide array of equipment from the mainstream to the eclectic, and I have some observations that are very constant. While kingpin angle isn't the whole story, in very broad terms, skates with kingpin angles farther away from vertical are generally able to keep the wheels in contact with the floor longer in deeper turns than their more vertical counterparts.
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Old August 15th, 2015, 07:13 AM   #18
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I doubt that about higher kp/qction plates being able to use grip better, as they actually have less of it.


The harder you try to turn the more likely you are to actually lose grip. Because of the attack of the wheels vs the direction you are actually going. A stiffer setup or a steeper less truny plate wont turn as well but the skaters legs can apply more pressure laterally because of the wheels not losing their grip potential because they arent 1 scrubbing speed and 2 the angle of attack is less , and thus more stable.

If grip was infinite then da45 would be the best, but its not.

Again it depends on the skater, but less kingpin angle and longer plates if the skater can handle it, tend to perform better.

Now if you have the same turning arc for a given wheelbase, I currently think the da45 vs da10 argument to favor the da45 because of the grip diminishing as the plate has to lean way over, and the loading of the wheels to the floor would possibly be offset by the suspension resistances.

Ive skated a good bit of plates, wheels, floors and such. To write a bunch of accurate information would be hard to do and keep it pretty accurate because so many input problems can arise. Plate alignment on the foot/boot and ankle articulations make a difference as well. Im not a perfect skater, but I think I can push things to their limits, and be analytical about the differences of the setups and find the more critically contributing factors for what is altering performance.

One thing is certian though, wheels are the first interaction with the floor, and in this the most important aspect of the skates suspension.
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Old August 16th, 2015, 04:51 AM   #19
dvw
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I doubt that about higher kp/qction plates being able to use grip better, as they actually have less of it.
Sorry, my experience does not bear this out.

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The harder you try to turn the more likely you are to actually lose grip. Because of the attack of the wheels vs the direction you are actually going.
That's true of any skate.

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A stiffer setup or a steeper less truny plate wont turn as well but the skaters legs can apply more pressure laterally because of the wheels not losing their grip potential because they arent 1 scrubbing speed and 2 the angle of attack is less , and thus more stable.
Well if we're going to compare all things equally, the arc of the turn is the arc of the turn. The pressure the skater applies won't be fundamentally different. The difference in plate action angle comes into to play here because the <15 kingpin plate will run out of turning range well before the >15 plate will, but will be less difficult to control. But it also means that when it runs out of turning range, it's going to lift a wheel edge, and the faintest little lift is all it takes to break traction.

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Again it depends on the skater, but less kingpin angle and longer plates if the skater can handle it, tend to perform better.
Depends on your definition of "perform".

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Now if you have the same turning arc for a given wheelbase, I currently think the da45 vs da10 argument to favor the da45 because of the grip diminishing as the plate has to lean way over, and the loading of the wheels to the floor would possibly be offset by the suspension resistances.
Ah. You do get it. This is precisely what I'm talking about. The DA45 would take advantage of more of the wheels' grip for exactly this reason. The DA45 has less leverage trying to pull the wheel up off the floor.

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One thing is certian though, wheels are the first interaction with the floor, and in this the most important aspect of the skates suspension.
That's a bit like saying that the flour is the most important part of the cake.
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Old August 16th, 2015, 06:36 AM   #20
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Sorry, my experience does not bear this out.



That's true of any skate.



Well if we're going to compare all things equally, the arc of the turn is the arc of the turn. The pressure the skater applies won't be fundamentally different. The difference in plate action angle comes into to play here because the <15 kingpin plate will run out of turning range well before the >15 plate will, but will be less difficult to control. But it also means that when it runs out of turning range, it's going to lift a wheel edge, and the faintest little lift is all it takes to break traction.

there is also ankle articulation here, and lacking it will obviously set one up for failure, but the lifting doesnt always make one lose traction. Depends on the floor. Also.lets not forget the human suspension and lateral force part, which, if one is faster and more powerful with their thier strides and such then the way a low degree kingpin interacts with the floor by not over turning to lose grip can be a advantage. My skating buddy Scottie Thompson uses a proline, and obviously my Arius can out turn a proline, but we cant exactly out corner each other. Even with the same wheels or grip level.

Honestly the only reason I dont use a lower degree kingpin like a proline or an advantage is because the Arius is better at power transfer.


Depends on your definition of "perform".

To have the potential to deal with great amounts of lateral.forces so a skater my exert tremendous power without the worry of unintended slip.

Ah. You do get it. This is precisely what I'm talking about. The DA45 would take advantage of more of the wheels' grip for exactly this reason. The DA45 has less leverage trying to pull the wheel up off the floor.

Again this depends on the suspension. Between the 2 setups, but my friends cranked down 10 deg action @85 A super cushions vs my daughters 72A mag avenger, neither had a problem with the wheels lifting during hard cornering. Though they are both very good skaters with great footwork skills so I can only presume their ankles were articulating correctly for the best grip.

That's a bit like saying that the flour is the most important part of the cake.
Ehh. Kind of.


What I do know is that it hasnt mattered the kingpin angle for me when switching through other peoples gear and changing wheels. Traction is traction for me, the difference is the plate can turn a little more where I can keep my legs straighter on a DA45 and on a 10 deg probe or century I need to use my lateral ability a bit more. Neither plate configurations habe made me really turn more honestly. But recently I wore the same wheels on both my arius and the heavily modified carrera skate i have (probe plate) the carrera held better in the corners and I was faster on it.

Lateral leg speed and power is a much larger factor in turning than kingpin angle if you ask me. In some instances I think high kingpin angles can cause problems with skaters when they lose too much speed and habe their legs too straight is their leg speed isnt up to the task. Theres a lot to consider and its hard to make textbook right or wrong, but narrow wheels increase the PSI the urethane has to deliver to the floor, and i would say more often than not the grip will be better with the narrow wheel. If you habe the strength to shear the urethane off at that width though(make it slide), the hardness must go up or the width has to increase.
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