Can't accelerate past 40mph on my EX.N -- why?

[techyiam]

1 hour ago, yoos said:

commuting on her EX.N effortlessly. She hits 45+mph quite a few times throughout the video. First half of the video is accompanied by her 2000km review in Russian, second half is pure riding footage. She mentions that positioning your upper body sideways helps cutting through the air.

Thank you for linking the video. 

Some observations. 

Her shoes are more or less centered on the pedals, maybe a smidgen forward biased. And the pedals looked to be level.

When her speed bursts up past 70 km/h, the tilt of her torso is still more vertical than horizontal. It looks to me a basic forward lean. She may have twisted her torso ever so slightly. I wouldn't have noticed it if you hadn't mentioned it. I don't think it reduces her frontal area that much. Perhaps it is to help her balance the camera stick aerodynamically. Can't be sure. But since she said that it helps her cut down aerodynamic drag, I may experiment with it. Like a sail or an air foil, it can generate "lift" (except to the right or left) due to induced circulation. So I have to be careful. Her arms are on her side, or more often than not, in front. What I find significant is her effective use of the power pads to generate forward torque. She does so naturally and effortlessly. 

I don't find her that small a person. Is she really that light?

[yoos]

1 hour ago, techyiam said:

I don't find her that small a person. Is she really that light?

A person on an EUC always looks tall, especially from the selfie stick. Though I am terrible at estimating size and weight of people (neither do I find it particularly appropriate ), here's a group photo, she's the rightmost woman in the shot. I guess she might be in the same weight category as Skeptikos (~130lbs).

[Mayhem]

On 8/22/2022 at 2:29 PM, EMA said:

i'm not debating the modes, i described how they feels on EXN 

medium has more swing and require more confidence to push top speed, it also rise the pedals more compared to hard 

Imo Medium on exn has way too much of a pendulum. Constantly tilting the pedals front to back for acceleration and braking.
 

As George stated above soft mode is just effortless on the exn and you can hit top speed without even trying. ( just for reference I have v2 that came with the first batch of black boards & using the first accelerated stability update.) never had a reason to update again. If it ain’t broke don’t fix it….

but hey if medium was / is your preferred mode then cool. It’s all personal preference. 

Edited August 29, 2022 by Mayhem

[Mayhem]

On 8/27/2022 at 6:35 PM, Skeptikos said:

There are actually a lot of EX.N riders in Albany. I'm not sure what they're going to show me (I've been riding longer than most of them). But if nothing else I think it'd be fun to swap EX.N's and see what happens.

Well if you ever end up going into nyc for a demo day or something with your wheel. I’d do a swap to see how different your firmware is then mine. 

Edited August 29, 2022 by Mayhem

[Unipilot69]

Did you switch the lights around so the heavy end is in front? It may affect the braking but would make it slightly easier to move forward. I usually trolly mine backwards. It seems to walk itself that way. I commute with my ht version. I have to trolly the damn thing a half a mile through the airport. The imbalance is noticable.

 

[UtahRider]

19 hours ago, EMA said:

do you have an early batch ? maybe green board ?

your soft is probably way different from mine

Stop trying, this guy doesn’t want your help, it hurts his feelings. Just let him figure it out on his own like most of us did. Maybe he will hit the magical 41 mph some day then he’ll be off to something else (hopefully).

[GoGeorgeGo]

On 8/29/2022 at 3:03 AM, EMA said:

do you have an early batch ? maybe green board ?

your soft is probably way different from mine

yeah my exn was a green board. i didn't realize there was a difference in the black board performance. 

[GoGeorgeGo]

On 8/28/2022 at 8:27 PM, techyiam said:

Is your torso orientation more horizontally or more vertically? 

When you say your arms are shot out in front, are they oriented horizontally, regardless of the orientation of the torso?

When I read your underwater analogy, I am picturing your torso and arms oriented horizontally.

i tend to ride with my right shoylder slightly out in front. and when you throw your arms out in front you shoyld be able to feel the drag reduce. its like swimming in that uou put your arms together to create a triangle shape to cut through the air. even just holding up two fists in front of you close together will break the air and give you reduced drag. its harder to gain speed with arms at your side or back imo, i just am 6' tall and 200 lbs so my body is a giant sail, if you can just break the air in front of you you slip stream much nicer

[techyiam]

  

6 hours ago, GoGeorgeGo said:

i tend to ride with my right shoylder slightly out in front. and when you throw your arms out in front you shoyld be able to feel the drag reduce. its like swimming in that uou put your arms together to create a triangle shape to cut through the air. even just holding up two fists in front of you close together will break the air and give you reduced drag. its harder to gain speed with arms at your side or back imo, i just am 6' tall and 200 lbs so my body is a giant sail, if you can just break the air in front of you you slip stream much nicer

I think you hit the nail on the head.

For me, having one arm out made all the difference. Thanks.

However, I haven't try your triangle method. I think I will try that next.

 

Here is a quick update on my experimentation with body positioning to go 40+ mph.

Firstly, I did a quick test of twisting my torso at 35+ mph. I find it destabilizing for me. I don't think I will pursue this further at the current time. That is not to say it isn't a useful technique for who know how to utilize it.

In the end it turns out that the key was aerodynamic drag reduction. I can now maintain 71 km/h (indicated) on a flat road, without effort. Also, incidentally, the battery charge consumption rate is ferocious. Battery went down to 80% from full in just a few runs. Also, my V12 felt very stable, and planted at this speed on a smooth road with no wind gusts.

It was all in the body positioning. The key was to have one arm extended in front of your body. The other arm can by the side, or behind.

The extended arm doesn't necessarily have to be horizontal. In fact, it could be slightly angled upwards a bit. You have to experiment.

In my case, my shoes were basically centered on the pedals, with a slight forward bias.

My pedals were level.

My torso is much more vertical than horizontal. My body has a just basic forward lean.

As soon as I stop extending my arm out, I immediately lose speed, and find it more difficult to recover the lost speed, and maintain 70+ km/h.

[Bizra6ot]

@techyiam Yep aerodynamic drag has a big impact at these speeds, you can observe it on the logs with the average power used by the wheel with standing and sitting position maintaining the same speed

As you like to try new positions next time try this one

 

[yoos]

On 8/29/2022 at 2:26 PM, techyiam said:

Is she really that light?

I unexpectedly got a precise number, she weighs 128lbs, gear and backpack included