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Superbike vs 'Mortal' bike video series
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Partly in response to the common thinking that superbikes are better and partly to counter the idea that you have to spend a lot to be competitive - we're doing a little video series about making one of my staff faster.

The premise is to spend USD$1000 to put together a faster bike/rider package (with used parts obviously) than his existing superbike.

Hopefully this can help a few riders understand where best to invest for speed.

Episode 1
Episode 2
Episode 3

Comments on acting not required, budget didn't extend to getting in someone who likes the camera.

edit - changed title, let's see if this one works better
Last edited by: cyclenutnz: Dec 18, 18 12:01
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Instead of actors, how about some microphones? The voiceovers were ok, but the rest....
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Great work showing what can be done with the right bike and not a whole lot of money. Cool idea cutting down the cranks to 150mm. Be interesting to see how Tauranga turns out. What gearing have you selected for the race?
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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The equipment approach is easy to follow. I'd be very interested to know what what the positional goals were, especially what dictated the 150mm crank. For me especially:
  • angle from BB center to hip
  • knee angle at bottom dead center (or should it be crank arm on same line as BB to hip?)
  • whatever metric you use to arrive at the 150mm crank length - min angle between lower spine and upper leg?

It's remarkable to see head-on the 2 of you cycling side by side - he's just a fraction of your cross-section

Brian

Gonna buy a fast car, put on my lead boots, take a long, long drive
I may end up spending all my money, but I'll still be alive
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Re: Video about optimising position [ergopower] [ In reply to ]
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These are great videos! Thanks so much for posting them and taking the time to make them. I recognise the roads and will be in town in early-mid January, was tempted to duck across for Tauranga Half but travelling for a month so won't have easy ability to pack any gear.

I think your post title needs to be a little catchier, it should have far more views than this already!
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Interesting.

How did you measure the reduction of 0.02 in CdA?
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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cool

Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”
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Re: Video about optimising position [RChung] [ In reply to ]
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RChung wrote:

How did you measure the reduction of 0.02 in CdA?


https://www.velogicfit.com/3d-aero-product/


The good thing with 3D is that we don't get the perspective errors of using a standard camera so the hips count the same as the shoulders. We flatten the 3D scan into a 2D image for the analysis.


Obviously we're then making a Cd assumption to apply to the A. It's very helpful to have instant feedback on whether a position improves A or not.


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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Next time I'm in NZ I really need to visit

Brian Stover USAT LII
Accelerate3 Coaching
Insta

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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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In the last video, you could see he had to lift his head in order to actually see up the road. How much does this do to offset the gains from the new position?
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Re: Video about optimising position [gaukler] [ In reply to ]
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gaukler wrote:
Instead of actors, how about some microphones? The voiceovers were ok, but the rest....

We do have a good microphone on top of the camera, I'm just not very good at talking to it. The first episode was pretty bad on the sound front so we're working on doing better.
Probably do need to be wired for sound - all the kit we have was intended for doing training videos for bike fitters indoors rather than being out and about.
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Great videos! I’m really looking forward to the next episode.
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Nice vidoes and very interesting. His position looks so much better than on the Giant. The new stem looks like a 140 though. Is there a bike out there a superbike out there that would actually work for him? P4, DA?
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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Interesting videos. Thanks for posting.

In return I have some helpful advice.

The aerial shots of the swim in the second video show a gain of at least 5mins on a 70.3 swim if you can get the lower part of the left leg to stop coming totally out of the body line (almost at right angles to the direction of travel) when breathing and to point the toes on the right (and I suspect the left foot as well). I can't slow down the video enough to see what the cause of the problem is but the swimmer is unfortunately creating a lot of unnecessary drag. The left leg is coming out of line to re-balance the body. Swaying from side to side is usually from crossing the arms across the midline on entry or from an early catch on the non breathing side in an effort to lift the head out of the water to get air, or both.
Last edited by: Mark57: Dec 17, 18 20:26
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Re: Video about optimising position [Mark57] [ In reply to ]
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He's around a 26min swimmer now, so 5mins might be a bit much. 2mins to get to lead pack would be good.
I actually hadn't really looked at the drone footage, the crossover is pretty bad now that you mention it.
We'll review and work on improvements.
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Re: Video about optimising position [imswimmer328] [ In reply to ]
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imswimmer328 wrote:
In the last video, you could see he had to lift his head in order to actually see up the road. How much does this do to offset the gains from the new position?

Depends on how often he has to do it. So far the indications are positive that there is a significant difference.
His Trinity position required lifting to view up the road too - any really fast position will be the same. Being aero does come with some visibility tradeoffs. It's something that each individual needs to determine with their fitter - where they lie on the speed vs vision and comfort spectrum.
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Re: Video about optimising position [ergopower] [ In reply to ]
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ergopower wrote:
The equipment approach is easy to follow. I'd be very interested to know what what the positional goals were, especially what dictated the 150mm crank. For me especially:
  • angle from BB center to hip
  • knee angle at bottom dead center (or should it be crank arm on same line as BB to hip?)
  • whatever metric you use to arrive at the 150mm crank length - min angle between lower spine and upper leg?

Here are the stats from changing the crank length (170mm to 155mm in the fit). Min amount to cut a crank by is 23mm, hence the procured crankset being 150mm.


You can see that his min knee angle was quite compressed (68deg is my threshold for intervention) so the shorter cranks opened that up a lot (6deg).
His min hip angle also opened by 3deg which allowed us to lower his torso angle later.
Knee max was kept the same (raised saddle as cranks shortened.
Sitting angle (BB to hip) pretty much the same.

No marked impact on knee lateral travel ( a really good indicator of tension at hips) as he wasn't restricted (I had done his fit on the Trinity and he is well adapted) so there wasn't really scope for improvement. 20mm of knee lateral travel appears visually as straight up and down

Hip and shoulder stability all no meaningful change (within margin of error of rider repeatability)

By the end (18th iteration) still no change in knee or hip stability but min hip angle 44deg and torso angle 10deg.


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It's remarkable to see head-on the 2 of you cycling side by side - he's just a fraction of your cross-section

He's ~62% of my mass, so already a fraction of a normal person. The position magnifies that further.
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Re: Video about optimising position [cyclenutnz] [ In reply to ]
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That's really helpful, thank you

Brian

Gonna buy a fast car, put on my lead boots, take a long, long drive
I may end up spending all my money, but I'll still be alive
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