Sur-Ron - New Mid drive Bike
- Thread starter Allex
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macribs
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madin88 said:With so much sag you loose a lot of power. 45V would be 2,15V per cellliveforphysics said:
I wonder why they went with 25R and not LiPos?
For hard core modifyers maybe look into Li-Metal Cells? Half the size and weight of li-ion. 400Wh/kg 1200 wh/l.
These are in production now for "boutique" orders for high end users. Custom made to order in USA on A123 production line I think.
I have no idea of price, delivery time or performance but it might just give the needed edge for running such a hi power controller like the ASI 8000. If you think about it, you already got a great deal for a great bike and controller, to match that you need a great battery. As the design of the sur ron is a large part of what really makes it, getting the right battery pack can be tricky do to real estate is at a premium. Maybe the thin metal li at half the normal size can rectify that and make sure you get a usable pack in the original sized battery pack?
http://www.solidenergysystems.com
Contact them here; http://www.solidenergysystems.com/contact/
Spec Sheet: http://assets.solidenergysystems.com/wp-content/uploads/2017/09/08171937/Hermes_Spec_Sheet1.pdf
liveforphysics
100 TW
Peak power output for any battery happens when Vsag is 50%.
madin88 said:With so much sag you loose a lot of power. 45V would be 2,15V per cellliveforphysics said:
I wonder why they went with 25R and not LiPos?
madin88 said:With so much sag you loose a lot of power. 45V would be 2,15V per cellliveforphysics said:
I wonder why they went with 25R and not LiPos?
Indeed, so something like 22kw dissipated as heat in the battery pack (albeit short term) under that load, or maby 15kw lost going by the 25r specs. and according to ASI the BAC8000 is rated for 600A "absolute peak" phase current, so 720A is pretty keen also.
Obviously well beyond the useful/reliable range of max current for 25r's and possibly also the BAC8000 but perhaps things went better than was initially expected.
Anyway thanks for the info Farfle -ive been a fan of your work over the years also and keen to see the results of this cutting edge work.
liveforphysics
100 TW
I don't consider anything to be "beyond useful range" if it works. Its a hotrod not a commuter.
This setup has a ton of pulls on it, still working perfect.
This setup has a ton of pulls on it, still working perfect.
liveforphysics
100 TW
Those lithium metal cell dataaheets indicate they would be meaningful worse than the 25r for making power. Also, lithium metal anode cells sketch me out so much i would never want one to be stored indoors.
We have discussed doing an RC cell pack, but perhaps trying the 30t can cell first, which should offer something like double power density over 25r. A pack made from nanotech hobby pouches would be the easy path forward to have something functional, but more work to make it survive the high shock and vibe environment of a dirtbike.
We have discussed doing an RC cell pack, but perhaps trying the 30t can cell first, which should offer something like double power density over 25r. A pack made from nanotech hobby pouches would be the easy path forward to have something functional, but more work to make it survive the high shock and vibe environment of a dirtbike.
macribs
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I miss read the spec sheet, states 3 A discharge. I read 30 A discharge. I thought these pouches had C rating like the Sony vtc's. I really shouldn't do much reading without my glasses on 
I didn't even think about lipo, and as you say from battery cans the next logical step would be lipo. What was the name of that drag race lipo, was it lonestar? They should have even higher discharge cells then hobbyking.
I didn't even think about lipo, and as you say from battery cans the next logical step would be lipo. What was the name of that drag race lipo, was it lonestar? They should have even higher discharge cells then hobbyking.
johnrobholmes
10 MW
liveforphysics said:
Interesting to know. Peak power on a PM motor tends to be near 50% of unloaded RPM too, if I recall correctly.
johnrobholmes said:
Don't repeat this too often otherwise not so smart battery builders will think 50% sag is OK!
With good LiPos the peak power probably would have reached 40-50kW.
Someone should put it on a dyno than to see how much of this power the drive system can deliver to the rear wheel.
I think it would make sense to use the highest available reduction. Reduce the torque /load on the motorshaft and up with the RPM.
my fastace forks didn't even last 130km of trail riding, they literally drip oil even when parked. right fork leaks from the seals and the left is more worrying as it leaks from the base where the axel and brake mount are bonded. looking at the website it shows that is glued with a grub screw to locate it so i would assume the grub screw is the only thing holding that together in this state.
the front brake also leaks both from the olive connection and through the two halves of the caliper where its held together by a pair of torx bolts.
looks like ill be throwing the forks and brakes in the bin i just don't trust them.
the front brake also leaks both from the olive connection and through the two halves of the caliper where its held together by a pair of torx bolts.
looks like ill be throwing the forks and brakes in the bin i just don't trust them.
liveforphysics
100 TW
Peak power for any motor also happens at 50% efficiency. Peak efficiency always happens when core losses and copper losses are balanced 50/50%.
This motor gets warm after around 8-10 WOT (as much as possible without flipping) pulls up to ~60mph, but it's never been so hot i couldn't touch it for a few seconds, maybe sub 80-90degC external case temps. Inside motor it may be much hotter, hasn't demag'd yet though and no thermal protection is setup. The brakes and 25R cells have thermal issues before the motor.
This makes me think we are still north of 50% efficiency even with controller feeding it 32kW. I happen to have suitable batteries available to use for dyno testing. I was also recently given a 0-60vdc 2,250amp(2.25kA) CC-CV power supply, but no dyno where it's being installed.
Without the voltage sagging to 45vdc, but say 70vdc, should easily be feeding 40kW+ to the poor motor.
This motor gets warm after around 8-10 WOT (as much as possible without flipping) pulls up to ~60mph, but it's never been so hot i couldn't touch it for a few seconds, maybe sub 80-90degC external case temps. Inside motor it may be much hotter, hasn't demag'd yet though and no thermal protection is setup. The brakes and 25R cells have thermal issues before the motor.
This makes me think we are still north of 50% efficiency even with controller feeding it 32kW. I happen to have suitable batteries available to use for dyno testing. I was also recently given a 0-60vdc 2,250amp(2.25kA) CC-CV power supply, but no dyno where it's being installed.
Without the voltage sagging to 45vdc, but say 70vdc, should easily be feeding 40kW+ to the poor motor.
liveforphysics
100 TW
motomoto said:
I missed this earlier.
If you want to do it, cut motor hall lead and connect to ASI hall pins. Cut throttle wires and connect to throttle input pins. Cut and connect key switch wires to on switch pins. Motor phase leads conveniently just bolt up to BAC8000. Connect battery leads.
Now it's controller tuning software and Jackson being an experienced motor tuner has still been perfecting the tune. It's the game of optimized PID loops to enable milking every amp it can deliver while staying stable enough to not fault out. Also, 720amps isn't the max setting in the controller software, its 730amp, but 720amp is the best we can so far get stable.
Just in yesterday evenings tuning session we went from crushing the pack from 50v to 45v and eventually got it stable enough to race repeatedly.
After she gets a stiffer pack, it will again require being re-tuned to the threshold of stability.
snee said:
130km, but how old is the bike? Since they have stopped making the air chamber version with oil and just provide fastace with spring fork now. Also, at least here on forum, I've seen people prefering the Fastace to the DNM for the upside-down forks.
its a new bike only a few weeks old so no air chambers its a spring only fork.
it comes as is if anyone wants it depending on postal issues, obviously im not going to send it to america or russia at my own expense but if there is someone who wants the fork for parts within realistic range from west Australia and they want to pay poastal fees then they can have it.
im only offering because its failed my needs and is leaking oil now so if someone wants it for parts then that is better than going in the bin... otherwise that is where it will go.
just offering it as an option not as an argument..
it comes as is if anyone wants it depending on postal issues, obviously im not going to send it to america or russia at my own expense but if there is someone who wants the fork for parts within realistic range from west Australia and they want to pay poastal fees then they can have it.
im only offering because its failed my needs and is leaking oil now so if someone wants it for parts then that is better than going in the bin... otherwise that is where it will go.
just offering it as an option not as an argument..
motomoto
1 kW
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Thank you Sir. I will see what I can do with the stock batteries doubling the stock output, then I will pick out some
Lipos and make a case for them with some chopped carbon reinforced nylon filament in my 3d printer. I love doing
3d printing, it's a nice break from machining.
Allex
100 MW
Whats the stock controller output in Amps?
The stock battery is only good for 110Amps(11p Panasonic PF) and at this rate you will have a huge sag. Going above that will destroy the cells quite quickly and the totalt output power will go down due to V-sag.
So if stock battery is 67V fully charged and you wack the throttle, the output you get at fully charged pack is 100A*60V=6000W(if stock controller actually can deliver 100A?)
Now lets say if you pump 150A and the voltage goes down to 40V then 150A*40V=6000W same output but you are destroying the cells.
The stock battery is only good for 110Amps(11p Panasonic PF) and at this rate you will have a huge sag. Going above that will destroy the cells quite quickly and the totalt output power will go down due to V-sag.
So if stock battery is 67V fully charged and you wack the throttle, the output you get at fully charged pack is 100A*60V=6000W(if stock controller actually can deliver 100A?)
Now lets say if you pump 150A and the voltage goes down to 40V then 150A*40V=6000W same output but you are destroying the cells.
liveforphysics
100 TW
For short intervals it's not so rough on cells to pull down to 50-60% of no load for short bursts on a wide off period duty cycle.
Definitely will impact cycle life, but for a race bike that's rarely a concern, as race bikes tend to get totaled from wrecks before they can wear out packs anyway.
Definitely will impact cycle life, but for a race bike that's rarely a concern, as race bikes tend to get totaled from wrecks before they can wear out packs anyway.
:lol:liveforphysics said:
Surron should offer an empty battery box without cells for DIY. Using 30Q instead of the PF should make 10kW possible without much impact on battery lifetime.
Has anyone measured the inside dimensions of the box, or figured out how much 18650cells could be packed into by using honeycomb layout?
The 30T cell is nice, but i don't know about a source where they can be purchased.
liveforphysics said:
Well now i don't feel so bad about blowing a few hundred watts here and there on some of my wrong choices of motors or drivetrains for race bikes over time (that turned out to be reliable for many years). -Now that losing 20kw+ in the cells and (admittedly guessing) say 10kw+ in the motor is ok. :lol:
Also, here in OZ im maby not sure what hotrod really means to you but im guessing at present your chasing the max power and acceleration (on tar) like say a drag bike? And if a machine is intended for the drag strip i spose your right, driving the battery to 50% sag and motor to 50% efficiency would yield the outright max few seconds of power. and yea don't get me wrong, i spose for now its a fun game of just maxxing stuff out with no remorse to see what it can do. -its just the warming of the planet that concerns me, cos of the shared space ship thing. :wink:
Something you guys pushing the limits here have helped make clear though is that with just a few mods this bike is possibly capable of racing head to head with ice dirtbikes and winning, motomoto has done a fine job on that motocross track -but just so that folks know;
You really don't need that much power. -not on dirt at least.
As long as its real output that is delivered to the tyre, you can match them for acceleration up to about 85kph as shown here in a vid of a race that i didn't know was about, its from a couple of years back when the joby motored bike was running at just 11kw output and this is a competitors onboard.
https://vimeo.com/142813987
<iframe src="https://player.vimeo.com/video/142813987" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
<p><a href="https://vimeo.com/142813987">Grass Tracking at the Colo Rancho</a> from <a href="https://vimeo.com/user25743554">Mikey</a> on <a href="https://vimeo.com">Vimeo</a>.</p>
With a few of these well priced sur-ron's gathered together, i reckon the organizers of these types of events would give us our own class to battle each other in.
This would have to the the most fun and cheap form of racing ever, that surely has to be the future?
liveforphysics
100 TW
"This would have to the the most fun and cheap form of racing ever, that surely has to be the future?"
Amen.
And they can be raced at tracks in urban areas at all hours and don't cause a noise pollution issue.
We are sitting on the cusp of motorcycles and cars both all making the transition to EV, and the world will never look back.
Amen.
And they can be raced at tracks in urban areas at all hours and don't cause a noise pollution issue.
We are sitting on the cusp of motorcycles and cars both all making the transition to EV, and the world will never look back.
johnrobholmes
10 MW
liveforphysics said:
I sure hope so. My city is just over 100k people and the main strip gets downright oppressive from exhaust fumes when the air gets hot and stagnant.
motomoto
1 kW
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- Jun 28, 2010
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Great video toolman. I like the rear skinny tire, but a little more tire would have been good too.
I am getting stupid with this whole thing. I just ordered some 11" forks. I am going to make a new swingarm
for a wider rear tire set up and more travel. This is the Bee layered over a KTM sx85
