Land Speed Motorcycle

[liveforphysics]

Good luck on your runs my friend! Let us know how the pack did getting pushed harder.

 

[Frank]

It's probably okay to push them a bit, often they'll sag from sitting after charge and I've always thought it was the true resting voltage you wanted to use, not necessarily the end-of-charge voltage.

 

[InterestedinEVs]

It's probably okay to push them a bit, often they'll sag from sitting after charge and I've always thought it was the true resting voltage you wanted to use, not necessarily the end-of-charge voltage.

For standard use, I think that's probably true. In our case, we saw significant gains increasing charge voltage from 4.15V (trying to be nice to the cells) all the way to 4.3V. I've settled on the standard 4.2V per cell, but we may go a bit higher if we seem to need it. The cells we tested at 4.3V seemed fine and did have slightly better performance than at 4.2V.

 

[DogDipstick]

Maybe Luke can give some insight into that one! It's quite possible it's an anomaly of our test setup, too.

Arrhenius equation

I think it has something to do with that.

( *I really have no idea what " that" is, also

 

[Frank]

In our case, we saw significant gains increasing charge voltage from 4.15V (trying to be nice to the cells) all the way to 4.3V. I've settled on the standard 4.2V per cell, but we may go a bit higher if we seem to need it. The cells we tested at 4.3V seemed fine and did have slightly better performance than at 4.2V.

That's what I was trying to say, actually. Were they 4.3 "hot off the charger" or after resting a bit? Good luck BTW!

 

[InterestedinEVs]

That's what I was trying to say, actually. Were they 4.3 "hot off the charger" or after resting a bit? Good luck BTW!

Ahh, gotcha...Both? Average rest time was probably 10 minutes. They didn't really seem to settle much.

Thank you!

 

[liveforphysics]

Many of the high C rate pouches I've tested show best DC impedance at around 4.1-4.0vdc resting voltage. I don't know why impedance goes up slight at higher SOC%.

Maybe pre-heat the pack and charge to 4.3vdc and try to have it passing through the 4.1-4.0v SOC range as you're reaching top speed and need peak power.

 

[InterestedinEVs]

I'll need to look at some data for that one. I'm not sure we have enough energy to be in that range. Thanks!

 

[InterestedinEVs]

Speed Week was canceled after a massive storm, with water up to 14" deep. The courses are said to be under about 4" of water in places. Hopefully it evaporates in enough time across the course to have the event, which is in two weeks and a couple days. Just playing a waiting game now.

 

[nicobie]

 

[InterestedinEVs]

BMST was officially cancelled on Saturday. We'll be reworking the front of the bike to add a brake suitable for the Texas Mile where we'll attempt to break Mobitec's 188mph EV record. New event date is the last weekend in Oct!

Edit: Reading some more, I believe breaking Mobitec's record would make us the fastest EV, car or bike, to run at a US Mile event.

 

[liveforphysics]

https://insideevs.com/news/595497/tesla-models-plaid-216-mph/

It says a lucid did 235mph in 2017.

But it wasn't done on the extremely difficult surface of salt.

 

[InterestedinEVs]

Sorry, I should have clarified. I don't mean the fastest bike or car in a standing mile, just the fastest to run at either the Texas Mile or the Colorado Mile events put on by the US Mile land speed organization.

 

[Frank]

FWIW: Lightning went 206 at Mohave in 2015 with an APS (i.e. streamlined tail) fairing. I went 206 at Loring with OEM bodywork in 2016. Best of luck!

 

[fechter]

Amazing the salt flats flooded. They keep whining about the Great Salt Lake drying up. Salt water and electronics is a very bad combination.

Is there someplace else you can run?

 

[PaPaSteve]

FWIW: Lightning went 206 at Mohave in 2015 with an APS (i.e. streamlined tail) fairing. I went 206 at Loring with OEM bodywork in 2016. Best of luck!

Pictures please

 

[Frank]

I'm pretty sure this is the Lightning at Mohave.

Me at Loring:

Video of a run in 2017 with cool batteries (these are Lonestar Sleeper Cells btw):

https://www.youtube.com/watch?v=aKpPurk5L7k

 

[PaPaSteve]

Me at Loring:

Video of a run in 2017 with cool batteries (these are Lonestar Sleeper Cells btw):

https://www.youtube.com/watch?v=aKpPurk5L7k

Thanks

 

[InterestedinEVs]

I'm pretty sure this is the Lightning at Mohave.

Hi Frank! I figured you'd be back by at some point. We're certainly not claiming to be very fast, haha. The 150kg class was low-hanging fruit. I think we've refined our team goals a bit to be the first 150kg class bike to go over 200mph. It will be a challenge on the salt and we don't have much HP for doing it on a short runway. We'll see. I think we'll get there, but it's all theoretical right now.

 

[InterestedinEVs]

Amazing the salt flats flooded. They keep whining about the Great Salt Lake drying up. Salt water and electronics is a very bad combination.

Is there someplace else you can run?

Ya, we could do El Mirage or Loring. Loring is long enough to get us to 200mph, I think. Honestly not sure if we have the motivation to do so, though. This all started as a way to get to Bonneville and have fun, not to become a professional land speed racing team.

 

[Frank]

I hear you Cole - Loring is in my backyard and although I've crewed at B-Ville I'd never make the effort to race there myself. You've got a unique vehicle and it'd be extremely cool to get the Hat in your weight class. :thumb:

 

[liveforphysics]

Awesome bike Frank! Congratulations on your work!

 

[InterestedinEVs]

^^^Seconded!

 

[nicobie]

......

 

[Frank]

Thanks guys. That was a 96S4P pack and the bike now has a 50S pack of Enerdels in it. I'm building a 60S pack of 21700's for it as the Enerdels are getting a bit long in the tooth. Actually, there's only one module getting weak but the 2170's are lighter and will have more capacity (the bike is street legal and I use it a fair amount). BTW, it went 149 mph with the 50S pack, the difference between ~85 hp and 225!