Pikes Peak, Electric Mountain Climbers...

[liveforphysics]

Sorry guys. If the motor is anything like the crystalyte HT, it will have to shed about 1000w worth of power at the most difficult parts. It will also drop out of it's efficiency range at those parts and dip into the 50% - 60% eff. range if it's anything like the HT, and i do believe it will be like the HT, going off it's diameter.

No. It's nothing like the clyte HT. Nothing remotely similar.

The lower efficiency of taxing one motor hard means i have to carry even more batteries. I am already looking at 30AH of 20s lipo at an absolute bare minimum. Running two motors simultaneously means i should have double the torque and thus dropping out of the efficiency range won't be so much of an issue.

THIS IS NOT HOW MOTORS WORK. You will never match the efficiency with two motors that you would have with a single motor and twice the cooling. Two motors just means additional hysterisis loss, eddy current loss, friction and weight.

Unless a single motor is saturating its stator (which is NOT a concern here), it's ALWAYS unconditionally going to be most efficient to get the power you need from a single motor with twice the cooling than a pair of motors with half the cooling. Absolutely always, zero exceptions, 100% every single time.

When you go from 10amps to 20amps (and we're talking phase amps, not battery amps here), it EXACTLY makes 2x the torque, in a perfect linear relationship, every single time (as long as you're not in saturation, which again does not apply for this).

If you require 40ft-lbs of torque to climb, if you get 40ft-lbs from 1 motor, or 20ft-lbs apiece from 2 of that motor, the two motor setup will always be lower efficiency than the single motor doing the job. (once again, assuming you're not magnetically saturating the stator, which isn't a concern for our application.)


Every motor requires a certain amount of waste energy just to make it spin. Increasing torque on a motor that you all ready have spinning does not require any additional waste to make additional torque, aside from the copper losses it endures from the increased current, which would be exactly the same copper losses you would get if you were powering 20 motors or a single motor.

If you can shed the heat, and you're not saturating, it is ALWAYS UNIVERSALLY EVERYTIME most efficient to do it with 1 motor than 2.

Rewound pie. Or slower winding pie if it can be found. Then volt up.

The wind of the motor has no effect on it's continuous torque my friend. If the slot is stuffed well with copper as it comes, then it's setup the best it's going to be setup.

 

[neptronix]

OK, about torque splitting between motors, I was actually thinking of pumping a little more power per motor to get more torque to hopefully keep me closer within the efficiency band. I do understand that splitting the power equally won't = more torque.

I do wonder where the saturation point is on the GM hubs. I don't have the money to blow one and find out. Just wanted to keep far enough away from it..

So do you think that ANY hub motor would survive venting 1000w for any period of time... even well vented? that would be about my peak heat generation. 7% grade would seem to create 300w of heat. That seems manageable but the higher grades makes that heat go way up.

I'll be honest, i don't have a lot of money and the race build is going to wipe all my money for the year out. I can't afford to blow a motor trying to do a single motor run. That's one reason why i'm playing it safe here.

Maybe i'll call golden motor canada and see if they can work me a deal.

 

[gensem]

I think GM ll donate the motor(s) for the race, its a lot of exposure for free.

 

[Jay64]

Hey Luke, wouldn't saturating a stator be a concern here? j/k :lol: :lol:

 

[cell_man]

Luke, I agree with your comments in principle but at the same time, any motor has an efficiency curve at different rpm and loads. I think what Neptronix is concerned about is that a single motor will not be operating at it's optimum efficiency considering the load and rpm in this situation, so by sharing the load between 2 it should hopefully bring the motor into a more efficient operating zone. I am sure there must be situations where 2 motors can be more efficient than 1 if by the fact of sharing the load, those motors are brought into an efficient operating zone. Motor Dyno printouts already include the motor losses, so IMO and I am no way any sort of motor expert, if 2 motors allow the motors to operate at a higher efficiency than a single motor would, I can't see how it would be less efficient than a single motor operating in overload conditions. Most hub motors will give best efficiency in the 70-80% of no load speed sort of range and typically they are given a power rating by what it can produce at say 80% of no load AFAIK, at least on hub motors. If a motor is not strong enough to get into that sort of rpm relative to voltage it will be operating in a lower efficiency zone or overload.

BTW, thanks for for the kind words on that other thread... Top Man 8)

I'm actually quite interested in this Pykes Peak challenge and I will see if I can put together something capable. It will not be with a Magic Pie though Even though I do see the attraction.

 

[John in CR]

Yeah, I think it would be cool if we put our resources together to just blow them off the road with an ES logoed bike! Just put like 50ah on there and go for it! Lol!

It would be a whole lot cooler for 5 or 10 of us to be sitting there waiting for them at the top. BTW, warn the organizers that the time slip guy needs to head to the top a while before the race starts, because a car will be significantly slower.

 

[John in CR]

Sorry guys. If the motor is anything like the crystalyte HT, it will have to shed about 1000w worth of power at the most difficult parts. It will also drop out of it's efficiency range at those parts and dip into the 50% - 60% eff. range if it's anything like the HT, and i do believe it will be like the HT, going off it's diameter.

You can't just make stuff up as you go about motors about which you know nothing more than the exterior dimensions.

 

[neptronix]

Sorry guys. If the motor is anything like the crystalyte HT, it will have to shed about 1000w worth of power at the most difficult parts. It will also drop out of it's efficiency range at those parts and dip into the 50% - 60% eff. range if it's anything like the HT, and i do believe it will be like the HT, going off it's diameter.

You can't just make stuff up as you go about motors about which you know nothing more than the exterior dimensions.

I'm just going off every direct drive motor efficiency/power graph i have looked at. I played with the ebike.ca power simulator for hours to find the best motor - wheel size - voltage recipe too.

What i saw is that there is a relation between diameter and available torque and width of the peak efficiency band.
The Magic pie isn't a hell of a lot taller than the HS/HT.

Short of buying both of them and putting both of them on a dyno, an educated guess is about as good as we're gonna get here.

 

[liveforphysics]

Lucky for us, I have purchased a magic pie, and have 3 of the cylte motors all ready, and a dyno jet chassis dyno.

 

[John in CR]

Lucky for us, I have purchased a magic pie, and have 3 of the cylte motors all ready, and a dyno jet chassis dyno.

When you kill it, let's measure the inside lip diameter of the covers. I'd love to disguise Hubmonster as a Pie for the run. 8)

 

[liveforphysics]

Lucky for us, I have purchased a magic pie, and have 3 of the cylte motors all ready, and a dyno jet chassis dyno.

When you kill it, let's measure the inside lip diameter of the covers. I'd love to disguise Hubmonster as a Pie for the run. 8)

You got it bro.

 

[Whiplash]

Yeah, I think it would be cool if we put our resources together to just blow them off the road with an ES logoed bike! Just put like 50ah on there and go for it! Lol!

It would be a whole lot cooler for 5 or 10 of us to be sitting there waiting for them at the top. BTW, warn the organizers that the time slip guy needs to head to the top a while before the race starts, because a car will be significantly slower.

Agreed! How cool would it be to sit there and jokingly crack open a root beer while not even breathing hard! Lol! We need a pic of the ES members at the top watching the Opti guys come up while we are counting our money!!

 

[zombiess]

Yeah, I think it would be cool if we put our resources together to just blow them off the road with an ES logoed bike! Just put like 50ah on there and go for it! Lol!

It would be a whole lot cooler for 5 or 10 of us to be sitting there waiting for them at the top. BTW, warn the organizers that the time slip guy needs to head to the top a while before the race starts, because a car will be significantly slower.

Agreed! How cool would it be to sit there and jokingly crack open a root beer while not even breathing hard! Lol! We need a pic of the ES members at the top watching the Opti guys come up while we are counting our money!!

Bold talk there. Much better to accomplish before celebrating. If I'm in the USA when the next event happens I'm thinking of entering. All depends on what happens with my job.

 

[Whiplash]

Of course, its all in good fun! .........

 

[neptronix]

Lucky for us, I have purchased a magic pie, and have 3 of the cylte motors all ready, and a dyno jet chassis dyno.

Well, isn't that just convenient.

 

[Josh K.]

Hey Folks,

Well, Nice to see some interest. Here is some info...

A hub motor can do it, Our Strommer with a 600 watt continuos duty motor made it up 24 out of 26 miles this year.
Motor ran well, rider gave it his all, and ran out of energies, depleting two 36v 10ah lithium poly batts...

Our AstroFlight equipped pedal puller system ran well, and did not over heat, at 500 watts continuos duty.
My Cargo Bike drank 24 volts, and 40 amp hours of go go juice. Our Rocha Drive tested out real well, next year, we run
more power, with experiential knowledge and confidence.

Next year, it will be a faster event, sub one hour, 26 miles, 7.5 thousand feet of elevation...

I think I might have to bring my E tek equipped trike, with a Zero Motor Cycle battery for this one...

48 volts, 40ah, lipo4, 500 amp controller, 52 tooth chainring, and a bottle of red bull...

Maybe we should let Red Bull know about this event this year.

Okay, Here is the lowdown. Lone Duck camp ground is a cool spot to stay. All the Motorcycle racers stay here for their race, we can have our own area to camp, a fire, Good showers, and only about 10 min from the race start point.

I recommend getting started to get ready now. It's a big deal. And, I do recommend some serious thinking about the decent, as it is a long, steep ride down, and you have to have really good brakes. Unofficially, I think their is a little bit of a down hill race going as well. And, this is where Electric Mountain Biking is headed, Up and Down hill racing is where it is at now.
The Optipunks are coming down fast, mainly for filming and promotional materials, but fast, non the less.

I recommend signing up early, when registration is open, and getting it on the calendar for real. We are getting tired of hearing a lot of trash talk, Big talk, and no body else showing up.

We have raced up Mount Washington two times now, and up Pikes Peak two times now. Next year, we are taking names.

Peace, Josh K.
RunAbout Cycles

 

[Josh K.]

Brakes:

A recommendation about Disc brakes, and descending 20 or so miles down a mountain:

Don't get caught in a dangerous situation by using a brake with a plastic adjuster barrel !

I remember one of the first years back when Mount Washington was bringing it's alternative fuel days back,
when a few of us climbed the Mountain with some electric cars, Electric Motor Cycles, and E bikes. We had
made the mistake of counting on our regen braking to be the main defense against gravity's magnetic pull.
Well, the controller over heated and shut off, after about 10 min. The bike started to really roll, and so I used
my dual front disc brakes to stop me. Seemed to work well for a while, until all of a sudden, the brake handle
just released into my hand, and stopped against the handle bar...The Plastic adjuster barrels had melted off,
and the brake pad on the inboard side, released past the brake housing. Brake housings don't create much friction
and the bike starts to roll forward fast again. Had to drop the feet to the ground, and wear down my sneakers a
little bit, stopped and walked the rest of the way, to save my life.

Brakes are a very important thing to think about when preparing for a Mountain Climb. I am thankful that I used
two Front Brakes, one disc, and one V brake, because I had not counted on getting my wheel bashed in, and having
to run the rear brake disconnected to be able to ride flat free. Sometimes I consider dual front disc rotors, and wonder
if it would held to dissipate the heat, or if it would warp in a weird way, and possibly cause a lot of drag...

Sometimes I think about a regen braking system that powers a series of coils, or heater rods to create brake drag.

Nowadays, Generally speaking, I think a pair of V Brakes are great. Combined with an extra disc brake, You have
nothing to worry about. I look forward to scaling the Gornergrat with our new pedal Puller design. Thanks Ron Rocha
for creating this engineering design, and his years of experience from his EE days for Hughes Aircraft.

http://ronzebike.com/About_Ronz_Ebike_YY26.html

Ideas?

Thanks, Josh K.

 

[John in CR]

Regen braking is the only way that makes any sense for an ebike to go down mountains. If I make it, I'll be pushing for a second lap, so stop to recharge at your peril. I can't get back what I give up to the wind, but much of the rest is fair game.

 

[John in CR]

Agreed! How cool would it be to sit there and jokingly crack open a root beer while not even breathing hard! Lol! We need a pic of the ES members at the top watching the Opti guys come up while we are counting our money!!

Counting our money???? Hmmm, with the price of those Opti's and no problems selling them, I guess they should have plenty of spare change for a put your money where your mouth is bet, and count me in. Maybe SamTexas will man up and let me race an ebike against his twin turbo Z as part of the same trip, so I can make it a paid vacation.

 

[Jay64]

Brakes:

Brakes are a very important thing to think about when preparing for a Mountain Climb.

Ideas?

Thanks, Josh K.

Like mentioned earlier, I think it was veloman, a parachute. We used to use these for training in Track. It is a personal parachute to create drag. It is small enough to be used on a bike on the way back down.

Granted, it won't totally stop you. But it will give you constant drag all the way down the mountain, and let your brakes rest that much more. I grew up on Maui, and we used to watch cars burn up their brakes all the time coming down from the volcano crater. There definately is an art to driving downhill. Hmm, my mom did want me to build her an ebike. Maybe I should fly home, build her one, and do a bunch of testing running up to the crater. It actually holds the world record for climbing the highest elevation in the shortest distance, 38 miles. Training in Colorado and Hawaii. I could make a life out of this. :lol:

 

[Whiplash]

Cool! Now we got some interest! I already talked with the wife about it. I am fairly sure we will ne able to make it, funds and time off will be the only limiting factors but I will have vacation time built up by then so it should be good! This is looking to be a fun time! I can't wait to see who actually shows up and what they bring!

 

[kfong]

I've been up Haleakala several times, the elevation is not as high 10k vs pike's 14k. Hiking around the crater still gets you winded though. I wanted to bike down it but never got the chance. A friend of mine actually road his bike up the mountain and back, rim brakes took a beating though. Beautiful island, best windsurfing spot in the country. I miss sailing those waves.

Brakes:

Brakes are a very important thing to think about when preparing for a Mountain Climb.

Ideas?

Thanks, Josh K.

Like mentioned earlier, I think it was veloman, a parachute. We used to use these for training in Track. It is a personal parachute to create drag. It is small enough to be used on a bike on the way back down.

Granted, it won't totally stop you. But it will give you constant drag all the way down the mountain, and let your brakes rest that much more. I grew up on Maui, and we used to watch cars burn up their brakes all the time coming down from the volcano crater. There definately is an art to driving downhill. Hmm, my mom did want me to build her an ebike. Maybe I should fly home, build her one, and do a bunch of testing running up to the crater. It actually holds the world record for climbing the highest elevation in the shortest distance, 38 miles. Training in Colorado and Hawaii. I could make a life out of this. :lol:

 

[Jay64]

I wasn't saying it was as high, I said it gets to the height in a shorter distance. So it could be some good data for going up a steep grade for some good distance. Of course, the cooling data for thinner air won't be as usable. But it should be hotter ambient air, so maybe that will make up for it.

I actually grew up about 5 miles from Ho'okipa Beach, which is the one I'm assuming you are talking about if you are talking about waves.

I used to regularly race my sportbike up and down that crater road. Actually, I shouldn't say race, I should say "spirited ride". :lol:

Would it be possible to do a combination regen braking setup? Have some of the power go towards the batteries and some of it go to a dynamic brake? That way you can charge your batteries back up, but you can shed off the excess without killing your batteries or controller since its such a long ride back down?

 

[kfong]

Yeah I caught that Jay, just wanted to add to the info. Yes, Ho'okipa is the spot.

Just saw the new gen pie, active cooling! And 30% more torque. Should be a good motor for trails as well.

http://endless-sphere.com/forums/viewtopic.php?f=30&t=32334

 

[Jay64]

Ok, just wanted to make sure I was making myself clear, sometimes I don't word things clearly on the net. :lol:

I know you guys are talking mainly of doing a cheap build to really put it to the highly priced opti bikes, so that is where the hub motor is really a big factor. But how do you think an RC motor setup would do on this climb? Cost not being a major design of a bike build. I would like to take the bike I'm currently building to this event as well. Would there be any negative reasons to not use an RC build for this climb? (Besides cost.)