Wheel Ignorance


So chatting with a skater, who recently invited me to come out and refnounce, the subject of wheels came up. She has heard of/thought of getting two sets of wheels. However she didn’t understand the why. A lot of skaters just accept the fact, from other skaters, that when you play vs team X you need Y wheels so you don’t slide all over the place. Or when you play against Team C you need wheel set D so you’re not stuck in the mud. But do you know the why? If you did you might consider trying a different set of wheels that speed up your game exponentially. Seriously, I hate to use Nawty Dee as my go to example, but when she tried a new set of wheels she went from an average speed skater to keeping up with the speedsters and or lapping them!

heartless wheels

So I’ll try to make it as easily understandable as possible, and believe me my intent is not to make anyone feel dumb.  So there are three points to keep in mind wheel hardness, wheel size (and how both react with different floors) and finally your weight. yep your weight also plays a factor.

Now for starters, polyurethane wheels are measured by their hardness by a durometer (the  resistance to penetration) the higher the number the higher the resistance. Most ROLLER skate outdoor wheels fall between 78a – 84a. Skateboard wheels are measured the same but have different ratings and various sizes. Indoor ROLLER Skate wheels generally fall between 84a – 102a (few manufacturers make 102a+ and are quite rare)

so what the heck do these numbers mean? Well have you ever noticed that when you skate  on your track you seems to skate at a fine pace, but if you skate somehwere else you’re either struggling to stay on the strack because you’re sliding everywhere OR you’re skating MUCH slower than you usually go? That’s the hardness of your wheels working with/against the floor. So the lower the number the softer the wheel is (easier to penetrate) and therefor it better “grips” the floor you skate on. This is something you want when you skate on polished concrete, slick wood floors, new skate/sport court, or masonite. Now when you skate on a newly cured/coated wood floor, old skate/sport court, or painted/pourous concrete you might want to use higher rated wheels. they’re harder so they don’t grip to the floor (the floor can’t penetrate the rubber) and so the wheels just keep rolling.

Wheel size also plays a factor, this info comes from my experience as a longboard skater. Essentially the smaller the contact patch (the amount of wheel surface that makes contact with the ground) the faster you will roll. the math behind it, think newton, an object in motion tends to stay in motion unless something something an outside force.

Wheels will spin until gravity and contact with a surface slow it down.  When you’re skating, your weight, gravity and how much wheel surface touches the ground determines how fast you will roll, or rather how long before you STOP rolling if we’re being technical.

Wheel sizes are measured in millimeters, both the diameter, (how long across the circle of the wheel) and how wide the wheel is. As far as roller derby is concerned, there is one standard wheel sizes and two standard wheel widths. There ARE a few companies that make variations on these sizes, but for the most part when you look online you will find 62mm tall and either 38mm or 44mm wide. Again there are companies that make smaller wheels (shorter) 57,58 and 59mm tall. The benefit of smaller wheels is that they accelerate faster how ever it takes more effort to maintain that speed.

For arguments sake, because I had a friend look this over and she wanted an explanation. Imagine your average BMX bike and a Beach cruiser. One has 20″ wheels the other 24″. Now imagine that the same person sits on the BMX bike and pedals once for a full rotation. The wheels turn a full 2 times so the BMX bike goes 40″ (20″ x 2) before it starts to slow down due to external forces. Now Beach cruiser same person same thing, they travel 48″ before they start to slow down (24″ x 2) make sense?

Now back to the skate wheels. Wider wheels offer stability for newer skaters especially in the apex (turn of the track) when they crossover. Narrow wheels offer longer periods of max speed because it has less floor to deal with. I couldn’t come up with an example for my friend, but just trust my experience with longboards that you can go faster further. The only example that I can think of is Quads vs Inline skates.

So to review lower number wheels with slick floors and high number wheels with sticky floors is the goal. If you’re an experienced skater. You can skate a WFTDA Assessment with your eyes closed, can teach or explain how to turn around toestop, tomahawk or anything else related to skating I’d recommend that you try narrow wheels.  You’ll be surprised at your new results.

The last thing that no one wants to talk about, a female’s weight. If you are over 150 lbs ~ 70 Kilos or heavier (I’m a Guy pushing 230 lbs ~ 105 Kilos) SUBTRACT at least 2a from the duro rating of your wheel.  For example I use a mix of 96a,94a and 88a wheels. but because of my weight they are in essence GRIPPIER than what they are rated as. so its more like 93a,91a and 85a. I can’t prove this last paragraph other than what I know about physics and skater drill/game I’ve seen.

 

2 different skaters using same wheels and bearings. From the jammer line a third skater pushes each one with the same effort/force. The skater who has the least resistance will roll farther. The point of this post is that you have a better understanding of wheels. How to choose your next set by considering all the relevant factors and hopefully you’ll noticably improve your speed and stay on the track by being properly equipped.

For anyone who cares I went from Labeda Hecklers, to G-Rods to Lowboys (all wide wheels) to Heartless in a mix and match type setup. I’ll discuss mixing and matching wheels and wheel bearing in a future post so stay  tuned

9 thoughts on “Wheel Ignorance

  1. Good article. I think a big factor too is that a softer week deflects when you put weight onto it more so than a harder wheel. If the floor were transparent and you looked at it from underneath as someone put their weight onto the skates, you’d see a softer wheel spread out onto a larger contact patch where it actually touches the floor, and a hard wheel deflects less with a smaller contact patch. Bigger contact patch means more surface area of the wheel on the floor to grip, which is what you need for floors that are not very sticky on their own. On a freshly epoxied floor that is nice and sticky, you can get by with a harder wheel, a smaller contact patch, and still have enough grip because of the added stickiness of the floor. Downside of soft wheel and large contact patch is greater rolling resistance since some of your push energy goes into deflecting the wheels surface versus moving you forward, so they are slower….SmoPho.

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  2. Well written. I used both research and common sense in addition to what I’ve learned in all of my pricey college science courses to choose wheels. It made sense to me that with my small size I could afford a stickier wheel where if I were heavier I’d probably want a harder wheel that my weight would help to….umm..stick-ify a bit.

    I would imagine that weight/size would be a factor in selecting a wheel with respect to hub material…aluminum or not being the question.

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  3. I also wanted a substantial lip in a lower durometer for teetering on in turns. This was something you didn’t touch on, likely for simplicity’s sake, the relationship between lip and duromyer…how each effects your skating and how they effect eachother. There’s a lot more to wheel selection than many realize…rookies at least.

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  4. Reblogged this on Derby+Diapers+Blog and commented:
    This is a clear and articulate article which thoroughly explains why we choose the wheels we do for skating on different surfaces, with diverse body types, and when trying to achieve various objectives…or at least we should be taking these (and other) factors into account when choosing a wheel or combination of wheels. However, its complicated, and some skaters don’t understand the physics of it all. So, I thought that this post from derbystripes.wordpress.com (written by a quite knowledgeable roller derby referee) could help make sense of it all for anyone who still doesn’t quite know why they’re using one wheel over another. Enjoy.

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  5. the Wheel update | Unofficial Derby Official's Rantings

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