Rim Width and Speed?

[Sean_WV]

I'm not 100% sure this is in the right section, so mods feel free to move it to a more fitting location if need be.

I have heard several times here that a disc's speed directly correlates with the thickness of the rim. This is very clear in the discs with flight numbers, and seems to hold true in most cases... BUT when browsing inbounds I noticed that the JLS is a bit faster than a Teebird, yet when I pull out my QJLS and Teebird, the JLS has a slightly thinner rim. So is this just the exception or is the correlation between speed and rim thickness not necessarily scripture?

[DJ Sticky Feet]

You also have to take into account the inner diameter. The Prometheus, for example. Has the biggest PDGA approved rim, yet flies like a speed 9. Why? The disc is bigger, so the inside diameter will be about equal to something that has speed 9 printed on the disc.

[5QU166Y]

It's also helpful to remember that "speed" is not really a quantifiable attribute of a disc. It's just something that Innova came up with and everyone uses. It generally correlates to the rim width of a disc, but this is not always the case.

[Alcuin]

Speed on the Innova scale is taken directly from rim width. The JLS has a rim width of 1.6cm, so it would be a speed 6. The Teebird is 1.7, so it is speed 7. The Firebird is 1.9, so it is speed 9, and the Destroyer is 2.2, so it is speed 12. Rim width translates directly to "speed' in this system.

As far as the JLS feeling faster than a TB, or discs like the OLF or PD being called speed 10 when they have a Firebird wing, that's subjective. But the basis of the speed ratings devised by Innova correlate directly to the measurable length of the rim.

[Aim For The Chains]

and then there was the Prometheus. . . ?

Speed 16! ...

[PMantle]

Just some dumb random thought I had when playing a round alone. If one were test all discs(of same weight) in a giant windless warehouse by being able to throw discs flat at exactly the same initial velocity then measured the speed at a fixed location, say 250' away, would there be any surprising results? Would some lower labeled speed discs stand out as far as retaining speed at distance? What would be the fastest discs at 250? 350? Would it always correlated to rim?

[hugheshilton]

Originally Posted by Alcuin

Speed on the Innova scale is taken directly from rim width. The JLS has a rim width of 1.6cm, so it would be a speed 6. The Teebird is 1.7, so it is speed 7. The Firebird is 1.9, so it is speed 9, and the Destroyer is 2.2, so it is speed 12. Rim width translates directly to "speed' in this system.

This is actually incorrect. I used to think this was the case from the few "good" Innova discs that I new the rim widths of such as those you mention. However, if you look at Innova's flight chart at the discs speed 10 and higher and look at the PDGA approved rim widths, they are actually all over the place and do NOT correlate with Innova's speed ratings at all. Here are a few examples (and there's more):

Krait, Speed 11, rim width 2.3 cm
Tern, Speed 12, rim width 2.3 cm
TeeDevil, Speed 12, rim width 2.4 cm
Archon, Speed 11, rim width 2.3 cm

And there are plenty of other examples. Really the "speed" is just a marketing term made up by Innova so they could lay their discs out on a supposed grid. I've also heard people spout some nonsense about speed relating to how fast you need to throw the disc to make it fly its intended path and I think that's BS as well. Try throwing a Vulcan flat with the same 450 feet of power you throw a Boss with and see what it does. I can tell you it isn't going to fly the path shown on Inbounds' flight chart; more likely it will just cut-roll.

I really wish we would stop talking about speed at all. We could definitely line discs up by rim width. I don't think that tells you how they will fly either, but at least it has some grounding in objective reality unlike the "speed" rating.

[Aim For The Chains]

Originally Posted by PMantle

Just some dumb random thought I had when playing a round alone. If one were test all discs(of same weight) in a giant windless warehouse by being able to throw discs flat at exactly the same initial velocity then measured the speed at a fixed location, say 250' away, would there be any surprising results? Would some lower labeled speed discs stand out as far as retaining speed at distance? What would be the fastest discs at 250? 350? Would it always correlated to rim?

I have heard that slower discs actually come out of the hand faster or something like that. Not sure where or if im talking crazy but it would seem initially they might be faster and lose speed as flight ends. Distance drivers just seem to hold the speed longer and even to the ground as they are more aerodynamic.

I think nose/rim shape might have as much to do with actual traveling speed as thickness of the rim across similar speed classes too.

[DanJon]

How does the Archon have a 2.3 rim width, when its a Wraith wing?

Somethings not right.

[hugheshilton]

Originally Posted by PMantle

Just some dumb random thought I had when playing a round alone. If one were test all discs(of same weight) in a giant windless warehouse by being able to throw discs flat at exactly the same initial velocity then measured the speed at a fixed location, say 250' away, would there be any surprising results? Would some lower labeled speed discs stand out as far as retaining speed at distance? What would be the fastest discs at 250? 350? Would it always correlated to rim?

If we just had an awesome disc throwing machine that could be dialed in at certain speeds/release angles/etc. then we could really objectively rate discs on a "speed" scale. I've heard rumors that such a thing exists somewhere but it's always someone's secret project that some mysterious "they" have been testing. I would love to see such a thing; it would be awesome to use to test every disc on the market and get real flight paths for all of them when thrown at different speeds and release angles. Anyway, it's a nice pipe dream at least.