Stark Varg Racing Debut

#434
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8/19/2023 11:07am

I‘m curious to see how the Varg will do in Supercross. If the bike‘s handling is decent enough for those kind of tracks, I don’t see any chance for the ICE-bikes. The instant power and better traction are a hugh advantage. 

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7
8/19/2023 11:30am
#434 wrote:
I‘m curious to see how the Varg will do in Supercross. If the bike‘s handling is decent enough for those kind of tracks, I don’t see...

I‘m curious to see how the Varg will do in Supercross. If the bike‘s handling is decent enough for those kind of tracks, I don’t see any chance for the ICE-bikes. The instant power and better traction are a hugh advantage. 

I would love to see one of the top guys on an SX track on one. I bet they could do some amazing things

1
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8/19/2023 4:09pm
insider wrote:

Should be in their own class, end of story.

Exactly what they should have done with Four strokes back in 98.

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DadBod86
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8/19/2023 6:02pm

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

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The Shop

Beagle
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8/20/2023 9:48am
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

Actually we should start a "steam power is the future of MX" thread to divert the trolls from the Varg Tongue

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Richy
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8/20/2023 10:07am Edited Date/Time 8/24/2023 4:20am
chump6784 wrote:
Mike Sleeter is working for Stark over here in Australia and i was talking to him over the past weekend. He was saying that Stark has...

Mike Sleeter is working for Stark over here in Australia and i was talking to him over the past weekend. He was saying that Stark has been working with Motorcycling Australia on getting Starks on the line over here. 

He said that they have put forward a hp limit of 49hp for the 250 class and 60hp in the 450 class and they have a way to lock out the ecu's so the riders and teams can't mess with it. 

Apparently they are very close to lining up in Australia. Also check out Mike's instagram, there are some videos on there with average riders doing starts on a Stark vs a 450, the 450 got gapped 

Not sure I agree with a 49hp electric bike in 250's but it's good to hear info on the process of classifying these things for racing, so thanks for sharing 👍

3
8/20/2023 10:32am
chump6784 wrote:
Mike Sleeter is working for Stark over here in Australia and i was talking to him over the past weekend. He was saying that Stark has...

Mike Sleeter is working for Stark over here in Australia and i was talking to him over the past weekend. He was saying that Stark has been working with Motorcycling Australia on getting Starks on the line over here. 

He said that they have put forward a hp limit of 49hp for the 250 class and 60hp in the 450 class and they have a way to lock out the ecu's so the riders and teams can't mess with it. 

Apparently they are very close to lining up in Australia. Also check out Mike's instagram, there are some videos on there with average riders doing starts on a Stark vs a 450, the 450 got gapped 

Richy wrote:
Not sure I agree with a 49hp electric bike in 250's but it's good to hear info on the process of classifying these things for racing...

Not sure I agree with a 49hp electric bike in 250's but it's good to hear info on the process of classifying these things for racing, so thanks for sharing 👍

I'd say HP is a dumb and somewhat arbitrary number (area under the curve is far more important, as we learned when they chose standards for 4t). I'd say cleaner would be to keep them out of limited "development" classes, but if the 450 class is the top performance class, let them run whatever configuration.

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1
#434
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8/20/2023 12:47pm
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

Beagle wrote:
Actually we should start a "steam power is the future of MX" thread to divert the trolls from the Varg 

Actually we should start a "steam power is the future of MX" thread to divert the trolls from the Varg Tongue

I shouldn’t have torpedoed the hydrogen motorcycle thread…

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2
8/20/2023 3:41pm
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

Beagle wrote:
Actually we should start a "steam power is the future of MX" thread to divert the trolls from the Varg 

Actually we should start a "steam power is the future of MX" thread to divert the trolls from the Varg Tongue

Riding technique would need to change, or heat resistant pants...

image-20230821083950-1

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insider
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8/21/2023 12:54am
MotoE is a standing joke in road racing. The bikes weigh near 600lbs and race slowly over about 20 (twenty) miles. They are so range limited...

MotoE is a standing joke in road racing. The bikes weigh near 600lbs and race slowly over about 20 (twenty) miles. They are so range limited they don't do a sight lap and the spectators are all on first name basis.

No one doubts an E MX bike with a powerful motor can be fast. The Stark is touted as the World's Best Motocross Bike.  Still huge uncertainty surrounds the battery range for a 30 minute plus 2 lap moto with a red flag restart. As much uncertainty exists as to if the bike can go more than a few laps without overheating either the battery, the inverter and, especially the rotor.

These low intensity novelty events picked by the Starkies is hardly answering if The Worlds Best MX Bike is really fit for purpose.

 

Beagle wrote:
Hi Goldie, I see that you're still irremediably attracted to any Varg thread. I'm glad that you're now pretty confident in the Varg's potential. Yes it's...

Hi Goldie, I see that you're still irremediably attracted to any Varg thread.

I'm glad that you're now pretty confident in the Varg's potential. Yes it's great that it is competing in national championships less than 6 months after the first delivery of a brand new bike unlike anything else on the market, from an unknown startup, but just like you I'm looking forward to seeing it kick ass in top events in the coming months.

[off topic] Anyway since you regurgitate the same arguments in all Varg threads I'd like to thank you for the opportunity to finally correct what you wrote about MotoE.

The current MotoE bike, made by Ducati in its first joint project between Ducati RD and Ducati Corse weights a hefty 225 kg, that's definitely more than even equivalent production bikes (and light-years away from a MotoGP bike) but still under 500 pounds. You got it wrong by over 100 pounds, I expected better of you.

About spectators, Dorna and the FIM chose to run the MotoE championship along MotoGP events so that tens of thousands of live spectators can watch the races at every event, that makes it hard to remember the names of so many people. Both MotoE races are held on Saturdays, race 1 sandwiched between MotoGP and Moto3 qualifying sessions, race 2 being the final event of the day right after MotoGP sprint race.

Finally about the range, absolutely, it sure is the main limitation with current tech and they do race about 30 km (that is half the MotoGP sprint race). Yet I would not call it slow, the progress in 5 years has been incredible and now they're about 3 seconds a lap from Moto2 (765cc) laptimes, nothing earth-shattering but pretty respectable. In 2019 Energica MotoE weighted 265 kg, it lost 15 kg in its final version in 2022 before Ducati took over with its first electric motorcycle losing another 25 kg. The technology has evolved so much in the past 5 years that Ducati keep smashing MotoE lap records by 2 to 3 s at every event while racing the same distance with a 10% smaller battery (18 kWh). Also 150 hp, >280 km/h top speed, 0-100 km/h in 2.5 s (similar to MotoGP), 0-200 km/h under 7 s is nothing to be sneezed at. 45 min to charge it up to 80% and you can safely plug it as soon as you come back into the pits (it's liquid cooled).

And of course it is a thing of beauty, forza Ducati! [/off topic]

​​​

All good that MotoE is hosted during Motogp events but the fans couldn’t care less for it. It’s used as an oppertunity to get something to drink and eat as it is too boring to watch.

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Beagle
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8/23/2023 1:04pm

Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open category (250 2 strokes, 450 4 strokes and anything in between, I think there may be an age limit of 25).

Anyway David Herbreteau on the Varg had the 3rd best lap in timed sessions out of 88 riders. Then he easily qualified for the Open finale with results in 4 races of 2nd, 2nd, 4th and 5th (group of riders were divided in half). Those 4 races were 8 laps long each (15-16 min).

Then in the finale race he got an issue during the 7th lap (out of 9) and did not finish. I don't have any details, it could be battery related however he had successfully completed 4 races of 8 laps finishing with full power so not sure what happened there?

With this DNF he still ranked 13/88 overall in the Open category.

I can't wait to see the Varg competing with pro riders, maybe at the french SX round this weekend!

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RACING
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8/23/2023 1:13pm Edited Date/Time 8/23/2023 1:16pm
Beagle wrote:
Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open...

Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open category (250 2 strokes, 450 4 strokes and anything in between, I think there may be an age limit of 25).

Anyway David Herbreteau on the Varg had the 3rd best lap in timed sessions out of 88 riders. Then he easily qualified for the Open finale with results in 4 races of 2nd, 2nd, 4th and 5th (group of riders were divided in half). Those 4 races were 8 laps long each (15-16 min).

Then in the finale race he got an issue during the 7th lap (out of 9) and did not finish. I don't have any details, it could be battery related however he had successfully completed 4 races of 8 laps finishing with full power so not sure what happened there?

With this DNF he still ranked 13/88 overall in the Open category.

I can't wait to see the Varg competing with pro riders, maybe at the french SX round this weekend!

From what I hear, Herbreteau's bike went into security mode.

Thomas Do should race the Varg in SX Tour on Saturday...

 

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Beagle
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8/23/2023 1:24pm
RACING wrote:

From what I hear, Herbreteau's bike went into security mode.

Thomas Do should race the Varg in SX Tour on Saturday...

 

Your post in the other thread made me check the rookies cup, thanks (I'm just trying to gather info about Varg racing in this thread).

Yeah I want to see what the Varg can do, short and intense SX races should suit the bike and we'll see if it overheats or not. Not sure if it will also race in SX1 with the big bikes ?

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burn1986
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8/23/2023 9:30pm Edited Date/Time 10/22/2023 7:41pm
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

That would be a cool idea. 
 

Like I mentioned in another thread, they could do the EMX World Championship. Of course it would only be the Varg lol. Maybe a few Surron Ultra Bees (Highly modified).

1
8/23/2023 9:33pm
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

Why should it be current production bikes, why not make it a true open class.

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DadBod86
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8/23/2023 10:52pm
DadBod86 wrote:

Make an actual open class/mx3 where you can run any current production bike. Could anything 2,4 stroke, electric, steam powered... would make mxdn way better too!

Why should it be current production bikes, why not make it a true open class.

Yeah, I suppose that makes sense, also a chance to dial in new models or parts for the main classes

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#434
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8/24/2023 1:21am
Beagle wrote:
Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open...

Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open category (250 2 strokes, 450 4 strokes and anything in between, I think there may be an age limit of 25).

Anyway David Herbreteau on the Varg had the 3rd best lap in timed sessions out of 88 riders. Then he easily qualified for the Open finale with results in 4 races of 2nd, 2nd, 4th and 5th (group of riders were divided in half). Those 4 races were 8 laps long each (15-16 min).

Then in the finale race he got an issue during the 7th lap (out of 9) and did not finish. I don't have any details, it could be battery related however he had successfully completed 4 races of 8 laps finishing with full power so not sure what happened there?

With this DNF he still ranked 13/88 overall in the Open category.

I can't wait to see the Varg competing with pro riders, maybe at the french SX round this weekend!

RACING wrote:

From what I hear, Herbreteau's bike went into security mode.

Thomas Do should race the Varg in SX Tour on Saturday...

 

Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks.

Could be essential to get the battery cooled down if it’s hot and there’s not much time between motos. Maybe go F1-style and use one of those:

FE491450-A8EB-48CE-847F-789B3DF92C69

2
8/24/2023 2:11am
Beagle wrote:
Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open...

Rookies cup is an event in France for youth MX with over 650 riders competing from various countries. There was a Stark racing in the Open category (250 2 strokes, 450 4 strokes and anything in between, I think there may be an age limit of 25).

Anyway David Herbreteau on the Varg had the 3rd best lap in timed sessions out of 88 riders. Then he easily qualified for the Open finale with results in 4 races of 2nd, 2nd, 4th and 5th (group of riders were divided in half). Those 4 races were 8 laps long each (15-16 min).

Then in the finale race he got an issue during the 7th lap (out of 9) and did not finish. I don't have any details, it could be battery related however he had successfully completed 4 races of 8 laps finishing with full power so not sure what happened there?

With this DNF he still ranked 13/88 overall in the Open category.

I can't wait to see the Varg competing with pro riders, maybe at the french SX round this weekend!

RACING wrote:

From what I hear, Herbreteau's bike went into security mode.

Thomas Do should race the Varg in SX Tour on Saturday...

 

#434 wrote:
Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks. Could be essential to get the...

Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks.

Could be essential to get the battery cooled down if it’s hot and there’s not much time between motos. Maybe go F1-style and use one of those:

FE491450-A8EB-48CE-847F-789B3DF92C69

More likely the motor/inverter overheated.

#434
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8/24/2023 3:16am
RACING wrote:

From what I hear, Herbreteau's bike went into security mode.

Thomas Do should race the Varg in SX Tour on Saturday...

 

#434 wrote:
Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks. Could be essential to get the...

Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks.

Could be essential to get the battery cooled down if it’s hot and there’s not much time between motos. Maybe go F1-style and use one of those:

FE491450-A8EB-48CE-847F-789B3DF92C69

More likely the motor/inverter overheated.

Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling it down after the bike ran shouldn’t be a problem.

The problem with short time between motos in hot weather is that the battery heats up during the race and charging puts additional heat into it. So there’s really no time and/or temperature gradient to get rid of the heat.

Straight to the wash bay to cool it with a hose could be a solution or a fan and a bit of water spray. 

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Richy
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8/24/2023 4:30am
I'd say HP is a dumb and somewhat arbitrary number (area under the curve is far more important, as we learned when they chose standards for...

I'd say HP is a dumb and somewhat arbitrary number (area under the curve is far more important, as we learned when they chose standards for 4t). I'd say cleaner would be to keep them out of limited "development" classes, but if the 450 class is the top performance class, let them run whatever configuration.

Generally speaking I agree but when we are settling on horsepower as the standard to regulate things, which we most likely will, allowing an electric bike with its power delivery a straight-up equivalency with a well fettled 250F feels like a bit of a blag.

Granted it's nowhere near the two stroke / four stroke double the displacement shenanigans pro AMA MX and SX pulled, but just seems a tad high.

1
8/24/2023 4:38am Edited Date/Time 8/24/2023 6:17am
#434 wrote:
Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks. Could be essential to get the...

Maybe the battery got too hot in the French summer heat? It surely was hot AF the last two weeks.

Could be essential to get the battery cooled down if it’s hot and there’s not much time between motos. Maybe go F1-style and use one of those:

FE491450-A8EB-48CE-847F-789B3DF92C69

More likely the motor/inverter overheated.

#434 wrote:
Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling...

Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling it down after the bike ran shouldn’t be a problem.

The problem with short time between motos in hot weather is that the battery heats up during the race and charging puts additional heat into it. So there’s really no time and/or temperature gradient to get rid of the heat.

Straight to the wash bay to cool it with a hose could be a solution or a fan and a bit of water spray. 

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...

 

The magazines need to measure the temperatures when they test the Varg.

Stark may have software protection so the battery cells don't reach 60°C, which is their maximum rated temperature...

image-20230824213507-1

If the battery pack did reach 60°C, you wouldn't want to touch the battery case...

image-20230824213647-2

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#434
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8/24/2023 4:43am
I'd say HP is a dumb and somewhat arbitrary number (area under the curve is far more important, as we learned when they chose standards for...

I'd say HP is a dumb and somewhat arbitrary number (area under the curve is far more important, as we learned when they chose standards for 4t). I'd say cleaner would be to keep them out of limited "development" classes, but if the 450 class is the top performance class, let them run whatever configuration.

Richy wrote:
Generally speaking I agree but when we are settling on horsepower as the standard to regulate things, which we most likely will, allowing an electric bike...

Generally speaking I agree but when we are settling on horsepower as the standard to regulate things, which we most likely will, allowing an electric bike with its power delivery a straight-up equivalency with a well fettled 250F feels like a bit of a blag.

Granted it's nowhere near the two stroke / four stroke double the displacement shenanigans pro AMA MX and SX pulled, but just seems a tad high.

Thought about that too. If you give an eMX bike the same or only 10% less HP than an ice bike, the ice bike won’t stand a chance in a drag race. No matter the rpm/speed, the eMX will have full power available. 

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Richy
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8/24/2023 4:43am
Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...   The magazines need to measure the temperatures when they test the...

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...

 

The magazines need to measure the temperatures when they test the Varg.

Stark may have software protection so the battery cells don't reach 60°C, which is their maximum rated temperature...

image-20230824213507-1

If the battery pack did reach 60°C, you wouldn't want to touch the battery case...

image-20230824213647-2

That's interesting, thanks for posting hard data (and Bryan of course for monitoring it and sharing).

Like #434 I had just assumed the battery would have been getting baked first, but thermal protection in the software does make complete sense.

Different game but even with the aftermarket/motorsport power distribution modules and many ECU's now board temperature is being monitored and is loggable/shareable data between devices allowing different strategies and safeguards, so heat management and it's importance seems to have taken a notable step forward in general.

#434
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8/24/2023 4:54am Edited Date/Time 8/24/2023 5:09am

More likely the motor/inverter overheated.

#434 wrote:
Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling...

Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling it down after the bike ran shouldn’t be a problem.

The problem with short time between motos in hot weather is that the battery heats up during the race and charging puts additional heat into it. So there’s really no time and/or temperature gradient to get rid of the heat.

Straight to the wash bay to cool it with a hose could be a solution or a fan and a bit of water spray. 

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...   The magazines need to measure the temperatures when they test the...

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...

 

The magazines need to measure the temperatures when they test the Varg.

Stark may have software protection so the battery cells don't reach 60°C, which is their maximum rated temperature...

image-20230824213507-1

If the battery pack did reach 60°C, you wouldn't want to touch the battery case...

image-20230824213647-2

Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem.

The battery is definitely protected by the system if it runs too hot, so you can’t possibly damage the cells. But why wouldn’t you wanna touch a 60 degree battery pack? Your skin disintegrates at 70 degrees, so you can easily handle something thats 60 degrees. A mug of coffee is hotter than that.

Edit: Thanks for the video btw. Very interesting! Temperature readings make sense. In general the battery system can tolerate much less heat than the motor/electronics in an EV. Tesla manages their batteries to a max 55C on the Supercharger, but let’s their motors run much hotter. So it makes sense to have a separate cooling circuit for both components. 

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vet323
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8/24/2023 6:08am
#434 wrote:
Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem. The...

Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem.

The battery is definitely protected by the system if it runs too hot, so you can’t possibly damage the cells. But why wouldn’t you wanna touch a 60 degree battery pack? Your skin disintegrates at 70 degrees, so you can easily handle something thats 60 degrees. A mug of coffee is hotter than that.

Edit: Thanks for the video btw. Very interesting! Temperature readings make sense. In general the battery system can tolerate much less heat than the motor/electronics in an EV. Tesla manages their batteries to a max 55C on the Supercharger, but let’s their motors run much hotter. So it makes sense to have a separate cooling circuit for both components. 

60°c will cause skin damage in 6 seconds. 70° will burn skin in one second. You aren't "easily handling" anything that's 60°c.

1
8/24/2023 6:33am Edited Date/Time 8/24/2023 6:37am
#434 wrote:
Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling...

Unlikely, both are water cooled and have a fan that can run in stand still. So cooling the motor/electronics while the bike is running and cooling it down after the bike ran shouldn’t be a problem.

The problem with short time between motos in hot weather is that the battery heats up during the race and charging puts additional heat into it. So there’s really no time and/or temperature gradient to get rid of the heat.

Straight to the wash bay to cool it with a hose could be a solution or a fan and a bit of water spray. 

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...   The magazines need to measure the temperatures when they test the...

Bryan's measurements showed the inverter runs the hottest, followed by the motor and battery...

 

The magazines need to measure the temperatures when they test the Varg.

Stark may have software protection so the battery cells don't reach 60°C, which is their maximum rated temperature...

image-20230824213507-1

If the battery pack did reach 60°C, you wouldn't want to touch the battery case...

image-20230824213647-2

#434 wrote:
Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem. The...

Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem.

The battery is definitely protected by the system if it runs too hot, so you can’t possibly damage the cells. But why wouldn’t you wanna touch a 60 degree battery pack? Your skin disintegrates at 70 degrees, so you can easily handle something thats 60 degrees. A mug of coffee is hotter than that.

Edit: Thanks for the video btw. Very interesting! Temperature readings make sense. In general the battery system can tolerate much less heat than the motor/electronics in an EV. Tesla manages their batteries to a max 55C on the Supercharger, but let’s their motors run much hotter. So it makes sense to have a separate cooling circuit for both components. 

When the media tester's rode the Varg prototype, videos showed a motor temperature of 59.2-70.3°C, and the inverter's transistors temperature of 48.9-112.8°C...

image-20230824232314-1image-20230824233615-1

Bipolar transistors can run at higher temperatures, but efficiency drops off with temperature...

image-20230824232928-2

Managing the inverter's temperature will be critical for efficiency and range.

Stark Varg 2.0 may need radiators in the traditional dirt bike location.

#434
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8/24/2023 6:39am
#434 wrote:
Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem. The...

Sure, motor and power electronics can run hotter than the battery and they are water cooled. So, I don’t think the motor/electronics is the problem.

The battery is definitely protected by the system if it runs too hot, so you can’t possibly damage the cells. But why wouldn’t you wanna touch a 60 degree battery pack? Your skin disintegrates at 70 degrees, so you can easily handle something thats 60 degrees. A mug of coffee is hotter than that.

Edit: Thanks for the video btw. Very interesting! Temperature readings make sense. In general the battery system can tolerate much less heat than the motor/electronics in an EV. Tesla manages their batteries to a max 55C on the Supercharger, but let’s their motors run much hotter. So it makes sense to have a separate cooling circuit for both components. 

vet323 wrote:

60°c will cause skin damage in 6 seconds. 70° will burn skin in one second. You aren't "easily handling" anything that's 60°c.

Compared to a hot four stroke engine after a moto I think it’s rather easy to handle. 

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rivvs
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8/24/2023 6:48am

It is the battery that overheat. The battery generate heat while discharging and charging and dissipating this heat is slower than the inverted and motor. Think of the battery as a solid 60 pound block. Taking the heat out front the center takes time. Also the temperature mesurement in the video are not a good way of measuring temperature. The temp on the outside case are not the battery temp you need temp sensor inside. If the case is at let say 88 degree the inside of the battery is higher than that. Also only one side of the cells a cooled. The negative of each cell is bonded to the case with thermal conductive compound. But that is only 21mm of the cell that is cooled. So you need the heat to travel from the positive of the cell to the negative then the case. The next for battery cooling is immersion cooling.

1
8/24/2023 7:00am
rivvs wrote:
It is the battery that overheat. The battery generate heat while discharging and charging and dissipating this heat is slower than the inverted and motor. Think...

It is the battery that overheat. The battery generate heat while discharging and charging and dissipating this heat is slower than the inverted and motor. Think of the battery as a solid 60 pound block. Taking the heat out front the center takes time. Also the temperature mesurement in the video are not a good way of measuring temperature. The temp on the outside case are not the battery temp you need temp sensor inside. If the case is at let say 88 degree the inside of the battery is higher than that. Also only one side of the cells a cooled. The negative of each cell is bonded to the case with thermal conductive compound. But that is only 21mm of the cell that is cooled. So you need the heat to travel from the positive of the cell to the negative then the case. The next for battery cooling is immersion cooling.

Do you have inside information that it was the battery that overheated on David Herbreteau's Varg?

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