Stark Varg on the Dyno

[TCMB371]

The video you've all been waiting for.

 

[C5tor]

I thought it was interesting that the dyno top speed showed about 10mph higher than the app top speed. Which one was correct? I am assuming one has a different tire size or final drive ratio in the calculation.

 

[rayivers]

Another outstanding video, Bryan - thanks again.

 

[Philip]

I think we probably should use the uncorrected horsepower numbers. The SAE correction for temperature, atmospheric pressure, and humidity should not apply to electric. The 79 HP number looks a lot better.

 

[TCMB371]

I think we probably should use the uncorrected horsepower numbers. The SAE correction for temperature, atmospheric pressure, and humidity should not apply to electric. The 79 HP number looks a lot better.

View attachment 9983

I think youre right actually.... hmmmmm

 

[Philip]

Here is the 80.0 HP on the third run, when the battery warned up a little.

According to confidential sources:

As the battery warms up a bit its internal resistance goes down a bit so more power can be delivered.

The vector control software has not been fully tuned yet. The commutation angle and flux weakening is not yet optimum through the RPM range. Therefore the funky shape of some power curves toward the higher RPM range.

 

[gewoontim]

I thought it was interesting that the dyno top speed showed about 10mph higher than the app top speed. Which one was correct? I am assuming one has a different tire size or final drive ratio in the calculation.

I think this has to do with the different dyno rear wheel that is installed. I wonder if the wheel size can be changed in the app (for supermoto for example.).

@TCMB371 could you maybe upload the PDF with the dyno graphs? Would be appreciated, thanks!

 

[blbills]

I did a screen grab of the chart and labeled the pertinent lines in the meantime. This confirms my actions to save $1K. Last week I modified my order down to the 60HP version. If I want to add it back later, I can.

 

[enjoythesilenc]

Dumb question. The yz will be putting down more power if it's ridden "on the pipe" than a standard 60 hp SV at motocross speeds?

 

[rayivers]

The yz will be putting down more power if it's ridden "on the pipe" than a standard 60 hp SV at motocross speeds?

I'd say no. The YZ's trace is above the 50hp SV trace from 50 to 85mph, imo above most non-Daytona MX/SX track speed ranges.. When I look at these graphs, I have to force myself to concentrate only on the left-hand side, as that's where I'll actually be using my bike. Looks like Stark definitely had SM in mind down the road.

 

[enjoythesilenc]

I was thinking the yz trace was done in top gear. Theoretically the yz should be able to make 50 hp in any gear and therefore make more power than a SV at speeds falling within whatever window is encompassed by a yz in first gear.

ie 30 mph: Stark is limited to about 35 hp no matter what? yz could be making max hp (50+) in first gear at 30 mph

Stark trace is set in stone (except for mapping) but yz trace can be shifted quite a bit to the left depending on gear selection. Maybe this could be a good talking point if stark is accused to have an unfair advantage over fire bikes.

 

[Philip]

Stark trace is set in stone (except for mapping) but yz trace can be shifted quite a bit to the left depending on gear selection.

The YZ can produce full horsepower in 1st gear at 10 mph, but it cannot put it down. Neither can the Stark Varg.

Even the 60-hp Stark Varg is traction limited and wheelie-limited below 50 mph. The power is insane.

The 80-hp Stark Varg is traction limited and wheelie-limited below 66 mph, according to ChatGPT. The aerodynamic drag is not taken into account.

It will be banned from Supermoto for life, LOL.

 

[rayivers]

I was thinking the yz trace was done in top gear. Theoretically the yz should be able to make 50 hp in any gear and therefore make more power than a SV at speeds falling within whatever window is encompassed by a yz in first gear. ie 30 mph: Stark is limited to about 35 hp no matter what? yz could be making max hp (50+) in first gear at 30 mph

Stark trace is set in stone (except for mapping) but yz trace can be shifted quite a bit to the left depending on gear selection.

Good points! I think if 450F gears-1-thru-5 dyno traces had their 'areas under the curves' averaged, the gearbox-related gains might be less than expected. Also, the Stark's final drive could be tweaked quite a bit to move a lot of RW torque down lower in the speed range with nearly the same rideability below field weakening; the ICE's could be too, but ime I found the bike accelerated faster but was more work / less fun to ride (1st gear barely used, shift/shift/shift, etc.).

I've been riding the ICE bike a lot lately (jetting, street only). Kinda like riding on impulse power.

 

[rayivers]

The YZ can produce full horsepower in 1st gear at 10 mph, but it cannot put it down. Neither can the Stark Varg...

+1 - and thanks for that HP-calculation info, never seen it before.

 

[jorn]

Isn't the point where power curve of the SV starts to dip down the point where the efficiency of the motor starts to drop, so you want to be below that to get maximum range?
And... the top speed above 90mph seems ridiculous for a mx bike. Is there really any mx tracks where that is possible?

 

[SubSonic]

think Chad saw his Dyno future and it likely just got dimmer -

 

[emax]

Hiya,

anyone in the know what type and size of tire this is, to cross check the power/torque figures? Cheers.

 

[RobG]

Based on Bryan's screenshot of the dyno HP vs speed chart, I've estimated RW torque and compared it to a KTM. The KTM is a 2017 450SX modified to 60 RWHP. The SV torque figures are approximate, based on the dyno chart and my estimates of primary gear ratio, sprockets and max rpm. It looks like the characteristics of the SV electric motor with probable low rpm current limit, then constant power limit then other reductions match the torque of an ICE with gears.

The top speed of the KTM in Supermoto setup is about 160 kph. No idea if there are any speed limits imposed on the SV by its controllers. If not, it could be a fast and capable Supermoto bike, but I'd like to hear from anyone that's tried it.

(usual warning... random posts on the web might contain BS... but the SV data below seems to match other quoted info at least approximately. The speeds are only dyno speeds, not actual.)

(edit: I found another reference for primary gear ratio, which drops curves by 5%...)

 

[Philip]

Based on Bryan's screenshot of the dyno HP vs speed chart, I've estimated RW torque and compared it to a KTM. The KTM is a 2017 450SX modified to 60 RWHP. The SV torque figures are approximate, based on the dyno chart and my estimates of primary gear ratio, sprockets and max rpm. It looks like the characteristics of the SV electric motor with probable low rpm current limit, then constant power limit then other reductions match the torque of an ICE with gears.

The top speed of the KTM in Supermoto setup is about 160 kph. No idea if there are any speed limits imposed on the SV by its controllers. If not, it could be a fast and capable Supermoto bike, but I'd like to hear from anyone that's tried it.

(usual warning... random posts on the web might contain BS... but the SV data below seems to match other quoted info at least approximately. The speeds are only dyno speeds, not actual.)

View attachment 10714

Oh wow! Even if geared for top speed, it will still beat the KTM 450 easily.

 

[Jocke_D]

Oh wow! Even if geared for top speed, it will still beat the KTM 450 easily.

My experience is kind of the opposite.
On stock wheels/gearing (18") rear my Varg tops out at about 135kmh according to the Varg phone. Or 145kmh measured with my own phone. The feeling is that over 120kmh it drops in power quite fast. Would be really interesting to see what taller gearing does. My FC450 tops out at around 180-190 with 17".
The advantage ICE bikes have being able to be in their power band in a much wider speed band (using every gear) will be hard to beat on tracks with low lowest speed and high highest speed.
Did a Supermoto race a couple of months ago and did not have any noticable power advantage other than in places where ICE guys had to select a gear and stick to it. I think we will need to use a taller gearing than what seem obvious to let the amps work. More testing will show what is the right way forward.