Owner's Review Stark Varg - First Customer Review!


rayivers

Well-known member
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CT, USA
Did anyone notice if the Stark used the Formula Brakes rear caliper with the LHRB setup? Or do they use a single-piston Brembo (bleh...)?

The demo bike had a Brembo rear caliper marked 22 8468 & 21 2F to go with the Formula LHRB MC. I've looked but found nothing on the Brembo - it may be a 22mm-piston caliper. :( At some point I'm going to research KTM adventure-bike rear calipers, might get lucky with a 30mm unit that bolts right on (not hopeful).
 

evh1

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Montgomery, AL
Well done, Bryan. Appreciate the candor and lap narration. I imagine the Stark fellows were impressed with your knowledge of E moto and bike/battery/components and Alta experience. The owner seems like a cool dude [ enjoyed his latest interview] and Tortelli must have been fun to hang with. I'm like you. The adjustability of the motor output will be fun to dial in as desired.
One question; was the throttle turn resistance easier and smoother than an Alta. I still get right wrist pump lol on the stiff Alta throttle.
I've ordered the 60hp version as 450 type motor is all ill ever want as I'm a woods rider mostly. Do you feel like this is a mistake and we should order the 80hp and just keep it retarded as you did?
 

Mark911

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Corona Ca
Super big HP numbers are easy with electric as the huge torque at low rpms can overwhelm any dyno (at typical motor rpms consistent with 1st gear). My little KTM 65 conversions could spike out at 25-30 hp between 0 and 1500 rpm, but it's just that, a spike, which drops fast and typically needs to be tuned out as it's impossible to ride. The only way to get accurate (real) hp numbers was to roll the throttle on relatively slowly. Then my 65s would measure 20hp max at lower rpms and drop from there. So, it's easy for me to see something like a Varg making an 80hp dyno spike for advertising, then de-tuning it.
 

TCMB371

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Well done, Bryan. Appreciate the candor and lap narration. I imagine the Stark fellows were impressed with your knowledge of E moto and bike/battery/components and Alta experience. The owner seems like a cool dude [ enjoyed his latest interview] and Tortelli must have been fun to hang with. I'm like you. The adjustability of the motor output will be fun to dial in as desired.
One question; was the throttle turn resistance easier and smoother than an Alta. I still get right wrist pump lol on the stiff Alta throttle.
I've ordered the 60hp version as 450 type motor is all ill ever want as I'm a woods rider mostly. Do you feel like this is a mistake and we should order the 80hp and just keep it retarded as you did?
The throttle spring tension felt about the same as our Alta's. Maybe a little softer, but I wasn't able to do a direct comparison. I'll just say i didn't really think twice about it so it wasn't a strange level of resistance to me.

The bike at 60hp is already super fast, and probably the fastest dirtbike you ever rode, and you'll probably be detuning it for the woods honestly. I personally won't be using more than 65hp or so. Anything more than that for me is just silly on a motocross track. In a 65hp map there was only 1 spot on the track where i was wide open. Everywhere else i was and estimated 25-50% throttle.
 

C5tor

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SF Bay Area, CA
The throttle spring tension felt about the same as our Alta's. Maybe a little softer, but I wasn't able to do a direct comparison…

You mean in that big barn of other manufacturers’ dirt bikes, they didn’t have any Altas? I’m hurt!

Mat Rebeaud didn’t have his Alta there?
 

fsfs

Well-known member
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HRV
Super big HP numbers are easy with electric as the huge torque at low rpms can overwhelm any dyno (at typical motor rpms consistent with 1st gear). My little KTM 65 conversions could spike out at 25-30 hp between 0 and 1500 rpm, but it's just that, a spike, which drops fast and typically needs to be tuned out as it's impossible to ride. The only way to get accurate (real) hp numbers was to roll the throttle on relatively slowly. Then my 65s would measure 20hp max at lower rpms and drop from there. So, it's easy for me to see something like a Varg making an 80hp dyno spike for advertising, then de-tuning it.

This is not some motor from company X connected to company Y's inverter that has no idea how to effectively flux weaken the motor at higher RPM. You can count on one hand the people who designed the motor, designed the inverter, and wrote the vector control software. At work they all sit within a few meters of each other. It is a classic power curve with constant torque up the the flux weakening knee and constant power after that.

Here is a dyno run of an Alta MXR from this very site - Test rode an Alta last weekend, here are my thoughts

s1200_ALTA_MXR.jpg



Look at map 4... It is pretty damn flat (not perfectly, but pretty close). The Varg is very similar, but there is just more power (bigger motor, bigger inverter, lower resistance battery). So if the Alta MXR can achieve this sort of power curve, why would the Varg have a large "spike"?

And if that still doesn't convince you, take a look at some of the journalist videos from before. Nobody complained that is was a "light switch" at low speed but didn't continue pulling at higher speed. The comments were that is was controllable and kept pulling.
 

F451

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WA State, USA
Well done, Bryan. Appreciate the candor and lap narration. I imagine the Stark fellows were impressed with your knowledge of E moto and bike/battery/components and Alta experience. The owner seems like a cool dude [ enjoyed his latest interview] and Tortelli must have been fun to hang with. I'm like you. The adjustability of the motor output will be fun to dial in as desired.
One question; was the throttle turn resistance easier and smoother than an Alta. I still get right wrist pump lol on the stiff Alta throttle.
I've ordered the 60hp version as 450 type motor is all ill ever want as I'm a woods rider mostly. Do you feel like this is a mistake and we should order the 80hp and just keep it retarded as you did?

I ordered the 80 hp because, why not? It sounds fun. I'll never ride on that setting except to try it out once in a while where I have a nice flat spot and plenty of room.

Meanwhile, when the day comes to sell it, I think it will make it a little easier to sell. Maybe the next guy wants a hill climb beast, or super moto setup, or road race bike, I don't know.

Plus every ICE bike knucklehead trying to give me crap for my lecky bike, I'll be like "How many horsepower you got in that thing? Oh, not even near 80? That's what I thought." Lol.
 

Bionicman

E powertrain proponent
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WA
with your thoughts regarding the rear brake actuation HB vs foot - I plan to leave my requested option of (used to) foot & hope theres a dual actuation option as I see the benifits of a hand brake modulation but used to a foot brake application...
 

TCMB371

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I'm curious about the simulated flywheel. Was this adjustable and was it impactful?

Honestly, I didn't really think about testing various flywheel settings. In the 2 days i really just wanted to feel out the bike and adjust power and engine braking to see how quickly i could find a comfortable "feel" in the bike. It took me only about 5-6 laps to figure out whether i liked more or less engine braking. Thats one thing i fricken love about electric, that you can make rapid motor characteristic changes in order to get a feel you personally like. No longer do you have to adjust to a bike's powerplant, instead you tailor the powerplant how you feel most comfortable. Its game changing in our sport, frankly. It takes a LOT longer to test various power parts and make modifications to internal combustion engines. With electric, all you need is your thumbs and a couple seconds. And your thumbs stay clean.
 

Mark911

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Corona Ca
This is not some motor from company X connected to company Y's inverter that has no idea how to effectively flux weaken the motor at higher RPM. You can count on one hand the people who designed the motor, designed the inverter, and wrote the vector control software. At work they all sit within a few meters of each other. It is a classic power curve with constant torque up the the flux weakening knee and constant power after that.

Here is a dyno run of an Alta MXR from this very site - Test rode an Alta last weekend, here are my thoughts

View attachment 9808



Look at map 4... It is pretty damn flat (not perfectly, but pretty close). The Varg is very similar, but there is just more power (bigger motor, bigger inverter, lower resistance battery). So if the Alta MXR can achieve this sort of power curve, why would the Varg have a large "spike"?

And if that still doesn't convince you, take a look at some of the journalist videos from before. Nobody complained that is was a "light switch" at low speed but didn't continue pulling at higher speed. The comments were that is was controllable and kept pulling.
Did I say anything about the "real" powerband? All I stated was it's easy to "fake out" many dynos with huge HP numbers just by how it's tuned and how the throttle is applied. I've set one on my Altas to a maximum RPM acceleration rate way above any of the standard map settings and on my dyno it would literally shred the knobs off the tire if I stabbed the throttle at 10-15 mph. When I managed to weight the bike to regain traction the spike HP numbers were unreal (unrealistic). Of course the bike would have been un-rideable at low speeds but I could have posted the fact that my Alta MX made 65 hp (as opposed to 40). That exactly why these bikes are detuned like the dyno charts indicate, to reduce and move all that torque to the right over an extended RPM range.
Unless you've incorporated some kind of magic which uses permanent magnets which can be significantly "de-magnetized" at higher rpm and then "re-magnetized" again at low rpms (also known as a variable flux motor/controller) using sophisticated D/Q axis algorithms, any ACPM motor will suffer from back EMF and require flux weaking to increase the speed/torque range. It's plain physics. Just claiming that the motor and controller were designed in collaboration isn't enough explanation in my opinion. Show me a dyno chart with the Varg making 80HP with a flat HP curve (similar to above) along with a concurrent battery current/voltage log and I'll be a believer.

Respectfully, Mark911
 

Bionicman

E powertrain proponent
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WA
Did I say anything about the "real" powerband? All I stated was it's easy to "fake out" many dynos with huge HP numbers just by how it's tuned and how the throttle is applied. I've set one on my Altas to a maximum RPM acceleration rate way above any of the standard map settings and on my dyno it would literally shred the knobs off the tire if I stabbed the throttle at 10-15 mph. When I managed to weight the bike to regain traction the spike HP numbers were unreal (unrealistic). Of course the bike would have been un-rideable at low speeds but I could have posted the fact that my Alta MX made 65 hp (as opposed to 40). That exactly why these bikes are detuned like the dyno charts indicate, to reduce and move all that torque to the right over an extended RPM range.
Unless you've incorporated some kind of magic which uses permanent magnets which can be significantly "de-magnetized" at higher rpm and then "re-magnetized" again at low rpms (also known as a variable flux motor/controller) using sophisticated D/Q axis algorithms, any ACPM motor will suffer from back EMF and require flux weaking to increase the speed/torque range. It's plain physics. Just claiming that the motor and controller were designed in collaboration isn't enough explanation in my opinion. Show me a dyno chart with the Varg making 80HP with a flat HP curve (similar to above) along with a concurrent battery current/voltage log and I'll be a believer.

Respectfully, Mark911
This very interesting & wayyy above my comprehension-overall makes me question the extra 1k im paying for the 80hp version when realistically I’ll likely spend a majority of my time on the detuned 30 hp 😅
 

Philip

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Lake Havasu City, AZ
The bike at 60hp is already super fast, and probably the fastest dirtbike you ever rode, and you'll probably be detuning it for the woods honestly. I personally won't be using more than 65hp or so. Anything more than that for me is just silly on a motocross track. In a 65hp map there was only 1 spot on the track where i was wide open. Everywhere else i was and estimated 25-50% throttle.
You looked scary fast by the end of Day 2. You were carrying a lot of momentum and accelerated hard only for a few seconds. That was impressive.

Then you cranked up the power to 80hp and the natural flow ended. Those pesky corners started coming at you too fast and unexpectedly too soon!
 

Philip

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Show me a dyno chart with the Varg making 80HP with a flat HP curve (similar to above) along with a concurrent battery current/voltage log and I'll be a believer.
If someone doesn't beat me to it, I will post that chart soon after I get my Varg. I will take it to the same DynoJet 200 where I tested my Alta MX and MXR.

I have no doubt that it will post about 80hp, and it will be a plateau and not be an instantaneous low-PRM spike. Else, the bike will be unrideable, and who would want to make/buy/ride such a a bike?

What we haven't tested on the Alta though is for how long that 50hp can be sustained. I am pretty sure it drops after a few seconds. This appears to be true for all EVs. In order to test for that, we need an electric or hydraulic (and not an inertia dyno), and we need to hold the bike at that Max HP RPM and at WOT until that horsepower numbers starts dropping. That would be an interesting test. Hopefully it would be longer than just 2-3 seconds for the Alta and the Varg. Because ICE bikes can sustain that horsepower until the water starts boiling and they start knocking, regarding the ignition, or seizing.
 

fsfs

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HRV
Hi guys. I don't mean disrespect for Mark, but if you look back at his posts he's been pretty negative about the Varg. I would consider it borderline spreading FUD about the bike with statements like "So, it's easy for me to see something like a Varg making an 80hp dyno spike for advertising, then de-tuning it."

There are two ways I can read this:

1. It can do 80hp in a very narrow RPM range -- basically has a large horsepower "hump" that must be flattened out in software to make it nice to ride.
2. Or dyno tricks - "When I managed to weight the bike to regain traction the spike HP numbers were unreal"

Neither of those if very flattering. Both imply some sort of trickery.

I am not trying to convince Mark of anything. All I am trying to do is to refute his claims of trickery for those that are positive about the bike and looking forward to it.

I will not post dyno curves at this time (I have to OK that with a number of people first). What I can do is show the current going into the inverter. Battery was charged to 80% SoC. Voltage sagged to about 365V because of current. Throttle was opened at about 50kph and closed when the motor got to RPM limit.

 

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