Specialized Turbo Vado SL: An Incredible E-Bike (User Club)

[Jeremy McCreary]

our bikes are equipped with the
S216800009 TURBO CONNECT UNIT DISPLAY (TCU)

The data fields are available with the
S216800020 MASTERMIND TURBO CONNECT UNIT DISPLAY

besides that, with are "traditional" touring bikes (like in camping trips with panniers) we do carry bike computers, mine is in my top bag so I can read after the ride what the metrics are of that day. For the SL's we use ROX4.0 computers, they connect to the E-bike via the TCU. https://sigma.bike/product/rox-4-0/

Sorry, I was asking about the TCU pages and fields you're actually using while riding (out of the many available).

For example, up to a month ago, I had only the 2 TCU pages below and simply toggled between them with the F1 button on the remote:

This 2nd page is on 90% of the time.

Then I added this range page out of curiosity but probably won't keep it:

 

[Stefan Mikes]

His TCU has no display. He uses Sigma ROX 4.0 computers for LEV ANT+ display.

P.S. I wonder whether the ROX can do Main/Range Extender LEV Batt % data field.

 

[Jeremy McCreary]

His TCU has no display. He uses Sigma ROX 4.0 computers for LEV ANT+ display.

Ah, yes. Forgot that some TCUs are like that.

I get a lot of use out of my TCU display. Good reason to pay extra for models that offer it. Highly and easily customizable, and always clearly readable in bright sun — even when I can't see a thing on my phone screen.

 

[Stefan Mikes]

Yes, it is definitely a good thing, especially as you cannot "crash" the top tube mounted computer in any way Specialized has been really good with its displays starting with the wired TCD-w in 2019 and then going through the wireless TCD (for Gen 1 SL e-bikes) etc. It was always five configurable data screens switchable either by the handlebar remote or the device buttons. The only small inconvenience for the Mastermind TCU is you need to look down to see the data, which makes is harder to use in rough terrain. That's why the recent Vado SL 2 has a Gen 3 display (H3) on the stem again.

The wealth of information available from Mastermind is impressive!

 

[Jeremy McCreary]

you cannot "crash" the top tube mounted computer in any way

Agree, well-protected from us mere mortals. But judging from some of the more spectacular crashes in recent top pro races, even that location might not be safe from a pro at speed on a carbon frame — especially when bikes tangle in group falls.

 

[2wheelsgood]

I must admit to not touching the motor tune settings since the first week of getting the bike over a year ago. When Stefan mentioned 60/100 and other configurations the other day I decided to have a play before the cycle to the gym yesterday.

Just out of curiosity I set the 3 points at 30/100, 60/100 and 100/100 and wow, that is some assistance! I didn't notice a huge drop in battery level over normal settings but I am sure it occurred. I might set it entirely the other way today and see how that feels

 

[Jeremy McCreary]

I must admit to not touching the motor tune settings since the first week of getting the bike over a year ago. When Stefan mentioned 60/100 and other configurations the other day I decided to have a play before the cycle to the gym yesterday.

Just out of curiosity I set the 3 points at 30/100, 60/100 and 100/100 and wow, that is some assistance! I didn't notice a huge drop in battery level over normal settings but I am sure it occurred. I might set it entirely the other way today and see how that feels

If you have MicroTune, I suggest playing around with it on a variety of rides before settling on any new mode tunings. Great way to vary assist in increments of 10/10 on the fly.

Most of my riding since purchase 10 months ago has been in factory ECO (35/35). However, with MicroTune, I'm discovering that (a) 30/30 would be sufficient for most purposes now, but (b) 40/40 would be a lot more fun. Unfortunately, the motor's at its noisiest at 30/30, so I won't be settling there for daily riding.

Writing a mode as E/M, if you tend to generate a lot of torque, you may find yourself burning a lot of battery with those uncapped M = 100 settings.

 

[Stefan Mikes]

Let me comment the two posts above.

The E/100 setting is appropriate for riders with relatively weak legs, especially when climbs are present en route. Such a setting is a real Carrot Effect as the rider is rewarded for the increased effort. (A rider with strong legs can benefit from 20/100 or 30/100).

My early experience showed the battery consumption was similar to 55/55% for the 30/100% setting but it was checked for my weak legs only. The 30/100% setting allows for more dynamic riding than 55/55.

 

[Stefan Mikes]

Guys, I made a short 8.4 km (5 mile) test of my SL at 60/100%. The battery consumption was 6.70 Wh/km (rather high). My Main + RE1 set is now degraded to 433 Wh, of which 390 Wh I perceive to be the usable charge. Meaning, the range would be at best 58 km. I'm going on a 61 km gravel ride on Saturday. Will stick to that assistance and let's see what happens. I will of course have RE 2 clipped in the spare water bottle cage

The racing configuration for wet conditions, RE 2 not clipped in yet.

I have found something funny. Whenever I activate speed derestrictor, the system produces Motor Error often. That is passed to my Wahoo (no effect on the stats) but whenever the ride is uploaded to Strava, Strava shows a crazily high Max Speed. Turned out, you can Correct Distance in Strava and then Strava will produce the real Max Speed

Another fun fact: I have been able to match the Wahoo Wheel Circumference to the GPS (map) within 0.6% accuracy.

"Correcting distance" may shave 50 metres off the ride but at least the Max Speed in Strava is correct!

 

[Jeremy McCreary]

Something to keep in mind if you routinely ride an SL at rider power Pr > 133W. Discovered this while modeling Specialized's power-sensing mid-drive PAS on www.desmos.com:

Writing an assist mode as E/M, in the very common case of E = M, you always hit the motor power cap set by M at the same Pr, regardless of E. For the 1.1 SL motor in the SL 1 and Creo 1, this "saturation" Pr = 133W, whether E = 10 or 100. Other Specialized mid-drive motors also saturate at Pr values in the 130-140W range.

Note that E = M in all factory mode tunings, and it's baked into all MicroTune levels as well.

Implication: If you find yourself wanting more help from your SL's motor at Pr > 133W with E = M, you'll have to bump to a higher M to get it. If you ramp up to, say, Pr = 233W, total power at the crank will increase only by the extra 100W your legs put in.

Good reason to have a TCU page like the one above.

 

[Stefan Mikes]

...but if you pedal harder than 133 W then M=100 means you get more motor power up to 240 W?

 

[Jeremy McCreary]

...but if you pedal harder than 133 W then M=100 means you get more motor power up to 240 W?

Not sure I understand. At E = M = 100, you already had the full 240W of motor power at 133W of rider power (Pr). Pedaling harder will get you more power at the crank, but the motor's already at max contribution. The rest is on you.

At E < M, the saturation Pr is higher than 133W by a factor of M÷E.

At M < 100, you have 2 options for more power at the crank past Pr = 133W with E = M: (a) increase M, or (b) get to work.

To see it graphically,

Visualizing and exploring the power-sensing PAS in Specialized mid-drives — an interactive graphical model

For our more math-minded Specialized mid-drive riders, here's an interactive graphical model of your bike's tunable power-sensing pedal assist system -- hereafter, just "PAS". The model doesn't cover complex PAS responses to transient events like starting out or approaching PAS cut-off speed...

forums.electricbikereview.com

 

[Stefan Mikes]

I meant E/M = 30/100.

Pm =133 W * 0.3 * 1.8 = 71.8 W but
Pr = 240 / 0.3 / 1.8 = 444 W

So, with the 30/100 SL assistance, the rider has to input as much as 444 W leg power to max the motor out. This is what I was saying: 30/100 or similar E/100 modes reward hard pedalling. I recommend E/100 modes as the single assistance to take you from the start to the finish through all the hills en route (with optional OFF mode).

Of course, I need a way more with my weak legs, perhaps 60/100%.

E/M = 30/30.

E/M = 30/100.

 

[Jeremy McCreary]

I meant E/M = 30/100.

Pm =133 W * 0.3 * 1.8 = 71.8 W but
Pr = 240 / 0.3 / 1.8 = 444 W

So, with the 30/100 SL assistance, the rider has to input as much as 444 W leg power to max the motor out.

Exactly, but E ≠ M in that case.

Let Px be the motor's peak power, and B the motor's boost. For the SL 1 and Creo 1, these are 240W and 1.8, resp.

Per Specialized documentation, above some saturation rider power Prs, Pm is capped at the motor saturation power Ps = Px (M / 100). Once the cap is in place, pedaling harder won't get you any more Pm than that.

In pseudocode,

if Pr <= Prs, Pm = Pr * B * (E / 100), else Pm = Px * (M / 100)

The blue graph of Pm vs. Pr above (Pr on x-axis) is a ramp of constant slope B E / 100 from Pr = 0 to Pr = Prs (orange vertical). At higher Pr, it's a flat (horizontal line) at Pm = Ps = Px (M / 100). The purple graph of total power at the crank (Pt = Pm + Pr) continues to rise after the orange vertical only because Pr does (red line).

It's useful to keep this geometry in mind. Since the ramp and flat have to meet at Pr = Prs, we must have

Prs B (E / 100) = Px (M / 100)

Solving for Prs gives

Prs = (Px / B) (M / E)

For the SL, Px / B = 133W. So when E = M on an SL,

Prs = 133W

Setting E = M couples the slope of the ramp to the height of the flat in such a way that they always meet at the same Prs = 133W, independent of E or M. Play with the graph. You'll see.

This is what I was saying: 30/100 or similar E/100 modes reward hard pedalling. I recommend E/100 modes as the single assistance to take you from the start to the finish through all the hills en route (with optional OFF mode).

Agree. Using M = 100 delays saturation to higher effort, but E/100 with low E puts max motor power Px out of reach for many riders.

The ramp-and-flat geometry of Pm as a function of Pr is still there. For 30/100, the flat's just raised to Pm = Px = 240W, while the ramp lengthens to Pr = Prs = 133W (100 / 30) = 433W to meet it, just like you said.

 

[Stefan Mikes]

Jeremy, I used your own app to draw my conclusions You use MicroTune so E=M. I advocate using E/100, where E must be set reasonably not to drain the battery too quickly. For instance, I know I can produce leg peak power of some 200 W. If I want to squeeze everything from the motor, I should use 67/100% (it is doable with BLEvo app used on my Vado SL early model). I, however, prefer having the assistance of 60/100%. My power meter reads my most typical leg power as 85 W. Given this, the motor would assist me with around 90 W. However, it will produce 240 W on a steep climb as I will dramatically downshift and pedal at a high cadence to deliver my 200 W (or more!)

As I said, everyone should find their optimum E if the M=100.

 

[Jeremy McCreary]

As I said, everyone should find their optimum E if the M=100.

Absolutely. I'll have to play around with these E/100 tunings. Haven't settled on MicroTune just yet but definitely playing around with it.

One thing to learn from all this math: The Specialized power-sensing mid-drive PAS is more flexible and nuanced than you might think. The factory tunings work quite well, but better tunings may well be waiting out there for a given rider.

Only testing will tell. Educated guessing can narrow the search.

MicroTune is a great tool for starting this exploration. Also helpful — but certainly not essential — to test with the ramp-and-flat geometry of the Pm vs. Pr relationship and an idea of the saturation rider power (Prs) for a given tuning in mind. With E = M tunings on an SL 1 or Creo 1, as in MicroTune, that Prs is always 133W.

 

[2wheelsgood]

So I did what I said and changed it to 30/10, 60/10, 100/10. At least I think it was 10 I cannot remember, it was the lowest it would go anyway,

I lasted 100 yards, it was horrible, my mechanical sympathy kicked in immediately on hearing the awful noise the belt was making. i stopped the bike and set it to 30/90, 60/90, 100/100.

I will keep tinkering, you guys have dragged me into the rabbit hole

 

[Stefan Mikes]

So I did what I said and changed it to 30/10, 60/10, 100/10. At least I think it was 10 I cannot remember, it was the lowest it would go anyway,

Easy to explain! Your E/10% setting limited the motor power to 24 W. A mid-drive motor cannot "breathe" or work properly at such low a power, it is just suffocating The reasonable value for the second number should not be lower than 30% (35% is even better).

 

[Stefan Mikes]

I lasted 100 yards, it was horrible, my mechanical sympathy kicked in immediately on hearing the awful noise the belt was making.

There's no belt only gears in SL 1.1 motor.

Additional info for my post #3,038:
The electric motor requires a minimum power to work properly, and I think it is 60 W for SL 1.1. Whenever the rider tries to force the motor to work at the power lower than the minimum, the e-bike computer produces a wave of ON-OFF states. The ON state provides 60 W and the OFF is 0. In other words, the motor rapidly goes on and off to meet the rider's low power demand. It is bad for the motor and noisy. It is a way better to ride without the assistance than go below 35/35% (the standard ECO).

 

[2wheelsgood]

Ah thanks Stefan, informative as always.

Is 35/35 the most quiet setting? or is there a tweak here I can do?