New hot rod yuba e-bike build

Joined
Mar 20, 2016
Messages
161
Location
Enid, oklahoma
Hello my name is Aaron Fuksa & this is my first post. I am building a high powered electric yuba mundo bike with a mid drive mxus 3t hub motor with thicker phase wiring, with purchased best 24fet 80-100 amp Lynn controller. The chainline will be re-directed to left side of wheel with a 1:3 gearing. The battery I'm deciding to buy is going to have two tubes on each side of platforms with Panasonic 3400mah cells, which will become a 103.6v 68ah nominal battery. I'm wondering when I'm finished what I might expect out of my bike.

My research and opinion says it should go 60+mph, out accelerate most vehicles, may pop a wheely & could flip if not careful & have enough battery to go 315 miles range using only 85% of battery at bicycle speeds while maintaining 19wh/mile energy use. Should set a new guineas world record for longest range on a single battery charge for a e-bike.
Other later additions are 12v lighting, turn signals, & accessories planned out already along with a custom cargo box I made. My bike will look nice and commercial looking and it name (Orange Streak). Most of the time it will be under cover legal 20mph programmed to be safe on the road, I'm a cautious slow driver, im all about saftey now... Wham truck hit me and he wasnt looking. Yes the bike will be pricey!!!

Any advice on what to really expect? & what others think. This is a drastic change for me from 72v lead battery. I hope to have pics up as soon as I can possible.IMG_20160321_114857_071.jpg
 

Attachments

  • IMG_20160321_114643_825.jpg
    IMG_20160321_114643_825.jpg
    257.2 KB · Views: 2,716
I expect you will find it high speed wobbles. Though a long bike is great for higher speeds, the Yuba frame lacks the torsional stiffness needed for a load that heavy, at 60 mph.

But hey, prove me wrong! I just think that speeds and weights like that need stiffer frames, suspension, etc. It's a motorcycle you are building after all.

I didn't say 35, or even 40 mph is out of the question though. :twisted:
 
dogman dan said:
I expect you will find it high speed wobbles. Though a long bike is great for higher speeds, the Yuba frame lacks the torsional stiffness needed for a load that heavy, at 60 mph.

But hey, prove me wrong! I just think that speeds and weights like that need stiffer frames, suspension, etc. It's a motorcycle you are building after all.

I didn't say 35, or even 40 mph is out of the question though. :twisted:

The bike will have performace upgrades when I get the parts. I can install a suspension fork to help bumps, though looks ugly, I'd rather get suspension seat post and the battery is very low and only wieghs under 60 lbs. Figuring how endlessphere works here.
 
orange streak said:
My research and opinion says it should go 60+mph, ...
...
Any advice on what to really expect? & what others think.
Expect 'big disappointment'.
I think you need to do more research...

60 seconds with the ebikes.ca simulator shows this bike will top out at 30mph.
(It will, however, climb a 20% grade at 25mph - if that's important to you.)


Although the motor will draw a max of 6kW during acceleration, when running flat out at 30mph it will be drawing about 1300W - as would just about any motor/drive at that speed. This speed is easily achievable with a small motor, 12FET controller, mounted as a conventional hub motor.

orange streak said:
...at bicycle speeds while maintaining 19wh/mile energy use...
19Wh/mi is enough to propel an 85% efficient bike on the flat at 20mph. Not really 'streaking'...

You don't actually call out requirements, so except to say that you claims will not be achieved, there's nothing to recommend except the obvious: your motor Kv, gearing, and wheel size appear woefully mismatched.

You really need to adjust the gearing downward (or go to a 2T motor to get a higher Kv).
With your planned 3:1 it should do 30mph. With 2:1 it should do about 41mph. With 1:1 gearing (as a conventional hub) it should about 56mph.

As the reviews indicate, the steel Mundo has a rigid frame (not sure about the newer CroMo frames) - there are few bikes with such huge top/down tubes and so much welded bracing aft of the seat post. Mine has 12000 miles on it and runs at 40mph pretty much like a freight train on rails. This is not to say that that's a Good Idea - at the end of the day, bike components on an unsuspended frame make those speeds a bit of a white knuckle affair to be undertaken only for short distances on roads known to be in excellent condition. 60mph? Not me.
 
teklektik said:
orange streak said:
My research and opinion says it should go 60+mph, ...
...
Any advice on what to really expect? & what others think.
Expect 'big disappointment'.
I think you need to do more research...

60 seconds with the ebikes.ca simulator shows this bike will top out at 30mph.
(It will, however, climb a 20% grade at 25mph - if that's important to you.)


Although the motor will draw a max of 6kW during acceleration, when running flat out at 30mph it will be drawing about 1300W - as would just about any motor/drive at that speed. This speed is easily achievable with a small motor, 12FET controller, mounted as a conventional hub motor.

orange streak said:
...at bicycle speeds while maintaining 19wh/mile energy use...
19Wh/mi is enough to propel an 85% efficient bike on the flat at 20mph. Not really 'streaking'...

You don't actually call out requirements, so except to say that you claims will not be achieved, there's nothing to recommend except the obvious: your motor Kv, gearing, and wheel size appear woefully mismatched.

You really need to adjust the gearing downward (or go to a 2T motor to get a higher Kv).
With your planned 3:1 it should do 30mph. With 2:1 it should do about 41mph. With 1:1 gearing (as a conventional hub) it should about 56mph.

As the reviews indicate, the steel Mundo has a rigid frame (not sure about the newer CroMo frames) - there are few bikes with such huge top/down tubes and so much welded bracing aft of the seat post. Mine has 12000 miles on it and runs at 40mph pretty much like a freight train on rails. This is not to say that that's a Good Idea - at the end of the day, bike components on an unsuspended frame make those speeds is a bit of a white knuckle affair to be undertaken only for short distances on roads known to be in excellent condition.

Thanks for your input, big fan. What i do know is Kinaye motorsports?, have pushed thier 3t mxus wheel hub motor to do 66mph!, on the drag on a youtube video. I was hoping to expect and do my best to achieve simular results with it as a mid drive setup on a 26" wheel. & hot off the charger is 117.7v, should give good results, just need to do it the best way it is possible. Thanks. I got to figure how to post pics?
 
As you can see in the posted plot above, I assumed a lean-forward mountain bike posture. If you re-run the simulation with your HOC voltage, 100A controller, 26" wheel, and drag tuck position, the result is 67mph for the simple 1:1 hub mount and 33mph for your 3:1 gearing mid-drive. As expected, the aero drag is the killer at higher speeds...

That 3T motor has characteristics that let it run pretty well as a hub motor for 'conventional use' -- adding steep gearing when running on the flat just doesn't work out.

Kinaye motorsports has spearheaded Mxus3K work in the states. Very reputable, excellent support.
 
teklektik said:
As you can see in the posted plot above, I assumed a lean-forward mountain bike posture. If you re-run the simulation with your HOC voltage, 100A controller, 26" wheel, and drag tuck position, the result is 67mph for the simple 1:1 hub mount and 33mph for your 3:1 gearing mid-drive. As expected, the aero drag is the killer at higher speeds...

That 3T motor has characteristics that let it run pretty well as a hub motor for 'conventional use' -- adding steep gearing when running on the flat just doesn't work out.

Kinaye motorsports has spearheaded Mxus3K work in the states. Very reputable, excellent support.

I think I made a mistake I assume its supposed to be 1:3 gearing which means wheel spins 3 revolution per ever motor revolution, a dumb mistake. Got some sample pics, Stay cool teklektik.
 
To give you some notion of what's happening here - check out this plot with a 100A controller and a 35A controller assuming your HOC 117V, 3:1 gearing, and tuck position:

ControllerStuff.png
The interesting thing is that both bikes achieve the same top speed - one with massive phase wires and giant controller, the other with a wimpy little 9 FET controller. This is a dead giveaway that for maximum speed the gearing is wrong for the 100A case. What this shows is that with your gearing, the motor simply runs out of rpm - it's not the controller or the ability of the motor develop power that is the issue.

The red curves show the power developed by the motor. The curve to the left of the inflection point (pointy peak) is where the power is limited by the controller while the right part is where the controller rating is pretty much out of the picture and the motor is primarily limited by voltage and Kv. The black Load Line is the power required to propel the bike at any given speed. The intersection of these two is where the available and required power are equal and the bike achieves top speed.

The plot above shows that the Load Line intersection is very far away from the peak motor power... because of the effective wheel size. Decrease the gear ratio to increase the effective wheel size and you will stretch the red curve to the right (more speed at a given rpm) - forcing the intersection to occur further up and to the right on the black Load Line. This allows the motor to reach a higher terminal speed by developing more power. The cost for higher terminal speed is that the blue thrust line moves downward as wheel size increases so acceleration and hill climbing go in the dumper.

EDIT - okay - see you crossed posted while I had lunch in the middle of writing this post. Anyhow, 1:3 is not too good either - but in the other direction. Anyhow, this post may help you interpret what's going on using the simulator so you can make a better guess at workable gearing.
 
Thanks see how it will roll when bike is ready to run. This is just a small example of what the bike will look like when the cargo box is mounted & will have pics when complete very soon. It is made out of lightweight aluminum composite sign panels, comes in many different colors & the aluminum corners & braces will have panels to hide the supports along with all of the rear wire lighting. Plan on mounting a bright flashing led whip light on the back. Eventually I will install a locking lid. I plan on eventualy selling my cargo boxes to others who have rear cargo bike decks. My box is 16" wide x 17" tall x 34" long with billboards built in with aluminum edging trim. Working on different low cost version to save money. The perfect cargo boxes for a cargo bike.
IMG_20160321_161052783.jpg
 
This all brings me back to the hanebrink X5 electric bike/motorcycle which unsuported claims of 80mph using the same motor mount idea and same controller, but through bicycle gears. Tried that idea and with less than 3hp tears up & breaks my rear wheel along with damaging your freewheel. Do not run a powerful motor through the bicycle gearing! I think Hanebrink uses a one of the crystallite hub motor. It does have good aero dynamics going for it though. At first I was thinking I could stick with the bicycle gears for a speed run and I could hit 70mph, ha! I asked about Hanebrinks setup & no answer was ever given. I love the fact that my bike will go further than any other e-bike for now, i plan to prove it, also because I haven't found a bike that has more battery capacity, just a claim for up to 250 miles from sunahme bikes from Canada, I'll have to check they have some thing like 5,500 watthour battery . Well back to work for now.
 
dogman dan said:
I expect you will find it high speed wobbles. Though a long bike is great for higher speeds, the Yuba frame lacks the torsional stiffness needed for a load that heavy, at 60 mph.

But hey, prove me wrong! I just think that speeds and weights like that need stiffer frames, suspension, etc. It's a motorcycle you are building after all.

I didn't say 35, or even 40 mph is out of the question though. :twisted:

Fact is it even the right thing to refer to it as a motorcycle when its power and speed can be adjusted with cycle analyst for 95% slow bicycle use speeds, & use the other 5% only during a event. My specs are can be true, but I don't plan on using thier potential, its mostly for bragging rights & its thier if you need it, etc. I'll see if this holds true, then some people can just back off a little when they here its potential. This is my honest opinion. :)
 
To orange streak.

Would your cargo box be better supported if the back wheel was 20" like what the xtracycle edgerunner have?

Right now I have a cargo bike (Kona Ute) but am looking to the future on which bike to purchase because of weight capacity due to carrying 400lbs total presently.
 
The Mundo is a terrific platform for modding... I'm prototyping my other one for a mid drive now too..the original does a solid 40 mph, and is stable enough to stand up on the pedals and ride no hands at top speed with a 2.2kw pack. But still, the back wheel is going to be taking sooo much load on bumps at 60 with the batteries back there...
IMG_20160321_183507.jpg
 
Nelsjourney said:
To orange streak.

Would your cargo box be better supported if the back wheel was 20" like what the xtracycle edgerunner have?

Right now I have a cargo bike (Kona Ute) but am looking to the future on which bike to purchase because of weight capacity due to carrying 400lbs total presently.
Even better on a lower center of gravity bike, as less wind resistance. Does kona ute have bolt holes on rear rack or I need to find clamps for tubes, to work.
The cargo box is in its infancy, weight, & sales are not final yet, but the box is built well very solid from back to front with aluminum channel or wood supports with aluminum angle on bottom sides that bolt to the corner. All bolts are stainless and don't rust. Panels give a clean look insides as well make it stiffer & stronger. Boxes can be made to customers size requirements.
 
Voltron said:
The Mundo is a terrific platform for modding... I'm prototyping my other one for a mid drive now too..the original does a solid 40 mph, and is stable enough to stand up on the pedals and ride no hands at top speed with a 2.2kw pack. But still, the back wheel is going to be taking sooo much load on bumps at 60 with the batteries back there...
Good point I'm all knowing about most wheel set ups. Yuba needs even better wheels, I tore many up with 96 pounds of lead batteries. You and I cant find stronger wheels unless made custom or custom from a company that's foreign for more money than my whole setup!. I'm waiting on skyway to make bigger wheels with disk brake. I'm stuck with original wheels & cool China aluminum mag wheels but can't get away from a 10mm axles with out paying unimaginable price until available to public. Show more pics later with mag wheels on!
 
The only think thats off whack for this build for me: I can put a sprocket on the back disk brake but I cant see how to also put a disk brake thier as well. Seems I will need to weld a nice tab thier to make a sprotor brake, preferably hydralic. I don't see enough room to mount a seperate disk brake with out getting to close to frame. Any ideas are appreciated. I love teklektik's ebike build.
 
Man those are some funky looking yuba bike to me with out the rear rack thier. Could do that & leave side platforms on for a even faster yuba if safe.
 
I didn't know the mundo was steel, or forgot it. That can make a huge difference with the frame stiffness.

I was thinking how alloy frames tend to be flexy side to side. This becomes a noticeable problem on many bikes once you add enough weight to the back. But in steel, you can always weld on additional stiffness if needed. Sounds like experience says it won't be as wobbly as I thought it might anyway. steel, even mild steel, has a very different feel at speed than alloy. To get the same stiffness as steel from alloy, the tubes need a lot of thickness, which bike designers hate.
 
orange streak said:
Man those are some funky looking yuba bike to me with out the rear rack thier. Could do that & leave side platforms on for a even faster yuba if safe.



That is a great thing about the first gen Mundo... the rack is bolted instead of welded... so it can go right back to bring a great passenger carrier :)
IMG_20150929_101632.jpg
 
Ya - the early Mundos are also super strong. In conversations with Yuba, they indicated that they couldn't source the tubing they wanted and so used thicker walled stuff to get production moving. The 5lb weight savings that first appeared in the v4.0 model came largely from finally building with the 'correct' tubing as originally specified. Modding one of the older ones has advantages....
:D
 
Hey guys I found one of those occasional events to go fast on my new yuba bike. Found a guy with a gas motorized Schwinn chopper bicycle & I want to race him with my new bike soon. with my 24 fet lynn controller, and mxus 3t hub motor, can I smoke him in a short drag race? He says it does can do a burnout and and can open up to close to 60mph. Then back to slow speed mode.
 
cwah said:
What motor is it?
I'm trying to find out again what motor, I left a message asking, great idea to record race, I don't see enough video of electric bicycles racing gas bicycle on the internet? Will be racing him in a month or less when bike is all together. I'll see about getting those gas motor specs.
 
Here is some turn signals and caution light I put on yesterday on my unfinished cargo box, they are bright leds. Yes 103v to 12v is doable a couple ways. Between the turn signals I'm putting my own custom reflective sticker I designed from some pics.

[ATTACH type="full" alt="IMG_20160324_181009.jpg[/attacment]
[attachment=1]IMG_20160324_181009.jpg"]0[/ATTACH]
 

Attachments

  • IMG_20160324_181009.jpg
    IMG_20160324_181009.jpg
    148.7 KB · Views: 2,408
  • IMG_20160307_131405_1.jpg
    IMG_20160307_131405_1.jpg
    267.9 KB · Views: 2,408
Back
Top