125V 80mph e-recumbent by Paul McDonald
- Thread starter sk8norcal
- Start date
MadRhino
100 GW
That is a neat build, and a very good example of the advantages of a fairing and a low profile bike.
Accelerating pretty quick to 80 Mph with power under 10KW is an outstanding combination of performance and efficiency.
Accelerating pretty quick to 80 Mph with power under 10KW is an outstanding combination of performance and efficiency.
samoloh
10 W
well I am just coming around on the idea of recumbent bikes, I didn't really like them, but the build changed my perspective cos the kinda look like Forumla 1 for e bikes. that 80mph is completely insane. Any body have info on the bike specs and details
RoadWrinkle
100 W
124 volts, maxing at 10,000 watts into a single rear hub motor? What am I missing? How is this possible?
Ypedal
100 TW
RoadWrinkle said:
For short duration, and not dogging it at low rpm.. = possible.
grindz145
1 MW
With the Cromotor etc, 10kw is no biggie, with THAT hub motor, it's pushing it a little. but 80 is still impressive (and scary)
Definitely has the right idea; minimize frontal area however possible.
Wonder what his wh/mi stats are at more normal road speeds?
10000watts/80mph = 125wh/mi
At 20mph?
(80/20)^3*p = 10000
p = 10000/((80/20)^3) = 156 watts
156watts/20mph = 7.8 wh/mi.
Not bad, I want that recumbent, lol.
My recumbent is pushing 330 watts at 20 mph. It's definitely not a racer, though better than those 'semi-recumbents'. (*wonders* does this recumbent have a suspension? *Watches* Front suspension but no rear suspension.)
Wonder what his wh/mi stats are at more normal road speeds?
10000watts/80mph = 125wh/mi
At 20mph?
(80/20)^3*p = 10000
p = 10000/((80/20)^3) = 156 watts
156watts/20mph = 7.8 wh/mi.
Not bad, I want that recumbent, lol.
My recumbent is pushing 330 watts at 20 mph. It's definitely not a racer, though better than those 'semi-recumbents'. (*wonders* does this recumbent have a suspension? *Watches* Front suspension but no rear suspension.)
RoadWrinkle
100 W
Look like the front suspension would consist of the knee pads and helmet :lol:
spinningmagnets
100 TW
Hubmotor Ventilation, Johns new approach, 3 pages
http://endless-sphere.com/forums/viewtopic.php?f=2&t=39773
Air cooling my X5 (40 pages)
http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=9791
Best waterproofing for inside a hub
http://endless-sphere.com/forums/viewtopic.php?f=30&t=36786
Doctorbass
100 GW
Congrat!
Thanks for the video.
Definitively possible as well.. i'm doing 70mph on a DH bike with big fat 24 x 2.5" wide offroad tire with about the same power on a 5303.. at 125V too..
Add better aerodynamic, tires and bigger motor and i have no doubt he did that 80mph.
Doc
Thanks for the video.
Definitively possible as well.. i'm doing 70mph on a DH bike with big fat 24 x 2.5" wide offroad tire with about the same power on a 5303.. at 125V too..
Add better aerodynamic, tires and bigger motor and i have no doubt he did that 80mph.
Doc
sk8norcal
1 MW
in the comments,
fairing by zzipper
fairing by zzipper
dnmun
1 PW
what controller is he using for the 10kW?
John in CR
100 TW
A question for those with recumbent experience...If you start to get a wobble, how do you react and change your CG enough to nip it in the bud before the harmonic oscillation has a chance to become catastrophic? I've had hints of wobbles on some of my bikes when I get too low and forward in a tuck, and my immediate reaction has been to raise up, which moves the CG up and rearward enough to immediately end the wobble. I guess I picked it up from Sir Anthony Hopkins playing Burt Monro, but all I know is that it works. Is there any way to do similar on a recumbent?
That's my biggest reservation about building a really fast ebike, because I know I can easily get a hubmotored ebike well above 120mph with some attention to aero, and the 22" wheel I have ready to go. I did 103mph with a 19.2" wheel and voltage sagging to 101V, so far faster is only a matter of aero and working up the nerve to do it. I wish I had a runway to use.
That's my biggest reservation about building a really fast ebike, because I know I can easily get a hubmotored ebike well above 120mph with some attention to aero, and the 22" wheel I have ready to go. I did 103mph with a 19.2" wheel and voltage sagging to 101V, so far faster is only a matter of aero and working up the nerve to do it. I wish I had a runway to use.
Doctorbass
100 GW
dnmun said:
A great 18 fets 4110 with caps upgrade can do that easy. Mine was able to peak 13kW( reading and 20kW ( amp x volt min)) and to sustain 9-10kW.
Doc
John in CR
100 TW
Doctorbass said:
It would blow as soon as you hit the throttle. He was 125V fresh off the charger, so 30s. Even if voltage wasn't an issue, the max power run through a controller varies greatly with motor it is pushing and the phase/battery current limit ratio. Speed winds typically come with low inductance and resistance and require beefier controllers along with lower phase/batt current limit ratios.
Doctorbass
100 GW
John in CR said:
yes probaly it woudl blow at 125V with the 4110 as well.. on my setup i was using 28s A123 and a 5302 ! on a 20" wheel. i saw sustained power of 11.5kW during most of the acceleration.
the 18 fet with 4115 would blow for sure...
Doc
I love these recumbent builds primarily for the aerodynamics and secondarily the comfort for longer rides. Although I would imagine going fast without rear suspension could be hard on the spine and this one is a little too low to the ground for riding in traffic. I bet that is amazing fun to ride. 
I have the same frame - lightning stealth/phantom. I put a 26" wheel on the front though. 35mph feels like nothing, and even with no fairing, efficiency is loads better than an upright. The problem is I need rear suspension too. I'm dismantling that ebike build because of it.
10kw at 80mph isn't all that great. Terry hershner is a bit under that with his upright aero modded zero s. A human powered streamliner is only needing 450watts at that speed.
10kw at 80mph isn't all that great. Terry hershner is a bit under that with his upright aero modded zero s. A human powered streamliner is only needing 450watts at that speed.
sk8norcal
1 MW
someone should convert the lightening f40,
velokraft is still my fav,
[youtube]efGOO69qAN8[/youtube]
velokraft is still my fav,
[youtube]efGOO69qAN8[/youtube]
Brother Paul
100 µW
For that speed run, I was running 125 volts 15 Ah LiPo batteries.
For the controller, Lyen 18 FET 4115 MOSFET
The motor was mounted in a 24" rim w/hookworm 24x 2.50 tire on the rear.
Temps on the motor stayed within perimeters.
However, on 3rd run down runway, the controller did blow smoke.
Next attempt will be :
HS 3548 Crystalyte motor … of course the motor will be properly ventilated with scoops.
Lyen 24 FET 4115 MOSFET controller
145 volts 15 Ah LiPo batteries
On paper, I should be able to exceed 100 mph with my recumbent bike frame's drag coefficient.
I'm using 0.07 CdA in the EBIKE Simulator.
It's a shame, they don't rate bicycles tires for 100 mph. I'm still looking.
I think I'll also be looking for a longer runway. I'm at the Cottonwood AZ airport.
Perhaps, Flagstaff Airport, less air molecules to run into at that elevation ( 7,000).
Paul MacDonald
For the controller, Lyen 18 FET 4115 MOSFET
The motor was mounted in a 24" rim w/hookworm 24x 2.50 tire on the rear.
Temps on the motor stayed within perimeters.
However, on 3rd run down runway, the controller did blow smoke.
Next attempt will be :
HS 3548 Crystalyte motor … of course the motor will be properly ventilated with scoops.
Lyen 24 FET 4115 MOSFET controller
145 volts 15 Ah LiPo batteries
On paper, I should be able to exceed 100 mph with my recumbent bike frame's drag coefficient.
I'm using 0.07 CdA in the EBIKE Simulator.
It's a shame, they don't rate bicycles tires for 100 mph. I'm still looking.
I think I'll also be looking for a longer runway. I'm at the Cottonwood AZ airport.
Perhaps, Flagstaff Airport, less air molecules to run into at that elevation ( 7,000).
Paul MacDonald
1KW said:
I think they are great for long commutes on open roads, or traveling. Not so hot for inner city stop n go / sidewalk cut-through, potholes, etc. The other main downsides is they take up more space to store or park at racks, possibly less visible in traffic, back sweat in the summer, not as good on poor pavement (can't unweight the bike). Not able to apply as much power to the pedals.
Overall, I like them, but it's not my everyday choice for an ebike setup.
Brother Paul
100 µW
Veloman, you forgot to mention, "Not so good in strong crosswinds."
However, on a beautiful day with smooth asphalt beneath you, there is nothing like opening the throttle all the way.
It's a spiritual experience … when space and time seems to warps all around you.
Paul MacDonald
However, on a beautiful day with smooth asphalt beneath you, there is nothing like opening the throttle all the way.
It's a spiritual experience … when space and time seems to warps all around you.
Paul MacDonald
