Build: $5k bike for 72mi Lake Tahoe loop in under 3hrs

[ryan]

My custom built Yuba Mundo was just stolen Now it's time for a new ride, with a new goal.

I'd like to build a bike for two purposes:
1) 72 miles around Lake Tahoe in under 3 hours, with minimal assistance. (Avg 24mph)

There's a bike race around the lake on September 11, 2016. So if I get it built before then I'd like to "race" for fun (maybe the day before or later start if I'm not welcome).

Distance            71.638 miles
Total Ascent        7591 feet
Lowest Point        6236 feet (at 5.76 miles)
Highest Point       7080 feet (at 62.97 miles)
Uphill              25.91 miles (36.2%)
Downhill            25.35 miles (35.4%)
Flat                20.37 miles (28.4%)
Max. Height Gain    843 feet
Steepest Uphill    +56.7% (at 61.63 miles)
Steepest Downhill  -40.0% (at 17.04 miles)
Longest Uphill      1.32 miles (at 58.51 miles)
Longest Downhill    1.21 miles (at 20.17 miles)

2) 25-mile round-trip flat commute
I'd like to cruise comfortably at 30-35mph, unassisted. I'm older now and don't need to chase speed records.

Considerations:
A) I really liked the Yuba Mundo as a platform. Plus, I have a bunch of kids and they can all come along on local adventures.
B) I'd like to ride more than build this one. I spent a TON of time building stealth battery packs into running boards. And other time consuming customizations. I'd like to avoid a monthlong build and just ride!
C) Budget: I'd like to stay under $5k if possible. I don't want to spend $5k, but I'm willing to go that high if necessary. If I could accomplish the same under $3500 I'd be stoked. This includes the bike. I think I can get a used Yuba Mundo for under $1k.
D) I have chargers in all varieties. But the rest will have to start from scratch. Most of my inventory was on my stolen Mundo.

I'll be looking for suggestions for:
1) bike/frame
2) battery setup suitable for the trip at speed
3) motor
4) controller
5) misc. -- I know I'll need a new CA, light, and other misc items. But if there's something else new I'll need, let me know.

I haven't paid much attention to ES over the past few years and have enjoyed re-familiarizing myself with new technology over the past few days, and seeing some familiar faces still pushing the envelope.

I look forward to your suggestions.

 

[tln]

I think I'd look at a recumbent with a bafang bbshd or tangent middrive and a bunch of the 4s 16000 batteries from hobbyking.

Recumbent will be a lot easier to get up to 35mph. Bafang so you can get your build going quick. Tangent to up your power and get up that big hill efficiently and quickly. 4s 16000 are cheap quick way to get a big battery. 12s 48a is less than $500. Then you can blow the rest of the budget on the best recumbent you can find

Sounds like a good budget and goal, good luck

 

[ryan]

Thanks for the help. I'm not sure I'd be comfortable on a recumbent, safety wise. I can't imagine commuting through a city with a low bent. People are already on their phones while driving. Making myself less visible isn't attractive.

I have been looking into HPC's LiNMC batteries. But I think I'd need four 63V 12.5Ah Li-NMC batteries for the trip, and at $1250 each, I'm already out of budget — before I get anything else. Building another harness, BMS, and the like using LiPo might be more than I want to take on right now.

 

[wesnewell]

A $200 48V 1000W kit will do what you want on a $129 Huffy Fortress 3.0 bike. On 12s rc lipo, you can make that 72mi. trip in under 3 hours easy with 2.5Kwh of batteries. Battery cost on sale was $540 for 2.66Kwh. Shipping cost from USA warehouse not included. No more than $100 though. Probably half that. Add $200 for misc. crap you'll want like a couple of battery medics and bulk charger, etc. $1200 total should do it easily.
http://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=48v1000w%20rear&LH_PrefLoc=1&rt=nc&LH_FS=1
http://www.walmart.com/ip/26-Huffy-Men-s-Fortress-Mountain-Bike-Blue/49058108

 

[ryan]

I'm not sure my budget is realistic. I've been trying to get up to date on battery tech. I imagine I'll need at least 60Ah (~3kwh at around 50V) to make the Tahoe loop and I'm having a hard time identifying the right balance of cost and density.

For example, I could get 3 packs of 51.8V 20Ah Li-Ion for $900 each ($2700).

Assuming $1000 for bike, $650 for motor, and $200 for the controller, $100 for the CA, I'm already at $4650.

 

[ryan]

Thanks Wes. Well that's an entirely different budget isn't it?!

So you're saying you would do the Tahoe loop under 3hrs with 2.5Kwh Hobby King LiPo on a 48V 1000W eBay kit on a cheap bike? All for under $1k? I know I've been out of the game for a few years, but I have a hard time believing tech has improved that much. I guess at that price I can go to the South Lake casinos with the rest of my $5k budget.

 

[wesnewell]

Tech hasn't changed much, but prices have come way down. I paid $275 for my kit 5.5 years ago. Can get the same kit today for under $200. Within the last 6 months I've bought 2 888wh packs of rc lipo for $180 each. Don't know why, I haven't even used them yet. Originally I planned on having to replace my lipo pack every 2 years. They just seem to keep going though. I'll let others fool around with weak 18650''s. Don;t get me wrong, I love 18650's for my flashlights.

 

[tln]

Thanks for the help. I'm not sure I'd be comfortable on a recumbent, safety wise. I can't imagine commuting through a city with a low bent. People are already on their phones while driving. Making myself less visible isn't attractive.

I have been looking into HPC's LiNMC batteries. But I think I'd need four 63V 12.5Ah Li-NMC batteries for the trip, and at $1250 each, I'm already out of budget — before I get anything else. Building another harness, BMS, and the like using LiPo might be more than I want to take on right now.

16s 32Ah would be $400 of that lipo... just saying. Maybe you could do with two of these though

http://lunacycle.com/batteries/packs/60v/60v-triangle-20-24ah-panasonic-pf-or-ga/

I suggested recumbent because power needed to reach 35mph is so much less, like 500-600 watts instead of 1500-1600 watts. Thats for a MTB though not a Yuba bus

http://www.kreuzotter.de/english/espeed.htm

A tangent drive might still be a cool option, given it's rated at 1750 watts continuous

 

[Alan B]

I'm so sorry to hear about the loss. It makes me so angry when ebikes are stolen. Reminds me of horse thieves in the old West. A hanging offense, as I understand it.

In terms of your new project, a friend of mine used to make the loop around Tahoe every year with a pedal bike, and that route is dangerous with traffic and no room for bikes, he said, as of a few years ago. I don't know if it has improved. I haven't done it myself. During an organized event it will be a lot better, hopefully.

For the long rides the recumbent is much easier on the body, but I totally understand the concern about handling and safety in traffic. It takes time to get that comfortable and skilled with a recumbent. The recumbent also requires less battery for the distance.

I think the Borg could make it with a good size secondary pack (or a couple of charging stops), but it would take quite a lot of battery due to the moped tire efficiency. These days the 18650's are lighter than the Lipos, but either way it is a lot of battery. But it would not be under 5K, at least mine wasn't. Especially with all the battery, though that is coming down all the time.

 

[ryan]

Thanks Alan. You're right about the Tahoe loop feeling dangerous. I hope that going out ahead or behind the actual event will help keep me safer, roads being closed and all.

Looks like I can get 52V80Ah with 4 of these 18650 packs (10lbs each) from Luna Cycle for $2500. 2 on each side of the rear wheel, on the running boards.

Do you think 4kwh with only 52V is enough to make that loop in under 3 hours though?

I'm thinking one of the new Clyte TC rear hub motors unless you all think I should look elsewhere.

 

[ryan]

A tangent drive might still be a cool option, given it's rated at 1750 watts continuous

Whoa! These Tangent Drives are awesome! This is the sort of tech improvements I was hoping to see since I've been missing from ES.

Are you familiar with these? Will this make my power use more efficient since I can use the rear gears? How's the noise level? Is it loud due to chain and small motor whine?

What would you suggest with this? $1400 for Tangent Drive (maybe more if I upgrade to Astro 3220), $1k for bike, leaves $2k for battery. I suspect I won't need as many kwh using a Tangent, which would decrease my overall weight as well. What pack would you recommend to fit the above requirements?

 

[Alan B]

The Tangent drives are amazing, though a bit on the noisy side. The BBSHD is silent but not as powerful, though at 1500W it is good for about 30 mph, depending on gearing etc.

My friend was on a ride around Tahoe when one of their group was hit by a truck mirror. Could have been bad. Be careful.

My BBSHD with 52V and 20AH went 26 miles of hard fast riding to exhaustion. That was 25+ and 1800 feet of climbing. Three of those packs should do your ride. My newest pack is 52V 24AH, so I have a bit more margin.

 

[Alan B]

3 AllCell 48V 20ah battery packs on a 750 watt motor kit will get you exactly what you requested. Under your $5k budget too.

What's the weight on those?

 

[ScooterMan101]

Your biggest problem is not the cost of a complete bike and e-components for $ 5k, you could really do it for around $ 3.5k ( getting less battery capacity )

You just need to forget about going 74 miles in just under 3 hours.

You could do that if you road a 74 mile course in Florida, or Holland, Denmark, etc.

But up at Lake Tahoe ?

Only the fittest of Road Bike Cyclists could even come close to that time frame, up at that elevation, ( and even then on 16 -19 pound , 110 + Psi tires, and an Excellent Cardio Vascular System ,
remember there are many climbs you will be doing around the lake, from 6,000 feet and above on the climbs. How long are you going to train up at that altitude, before the race ?

The Faster you want to go, and remember there are some good climbs around that Lake, the more battery weight you would need,
the more battery weight you have , the more power you need, then you need more battery capacity, which means a heaver bike which takes more power to get down the road, so more battery
which is more weight, so more power you use .

You want an efficient bike for that ride !

go a little slower , and do your conversion on a Road Bike or MTB with big enough wheels, and you will only need from around 25 amps to 30 amps max at 48 or 52 volts, to get around the lake.
( my Mac / Mtb build would get from 25 to 30 miles on a 48 volt 11 amp hour pack riding avg 12-16 mph. with 20%, or a little more of battery left ) and 30+ miles at average ride speed of 11-13 mph. )


Where does the Race start ?

Which direction does it go around , clockwise, or counterclockwise.

 

[dogman dan]

Hmm, to my rocky mountain eye, that climb is not really that big a deal. One 1000' vertical climb, ho hum. The rest just rolling hills, though the grades could be pretty steep at moments, especially if the road switchbacks any.

I sort of agree with Lester, you'll need about 3000wh to run it above 30 mph. Three of any kind of 48v 20 ah manganese cell packs would do er. That would weigh somewhere around 40 pounds. My allcell pack is not very high discharge rate, only 13 ah, so kind of saggy. But it's definitely well built, and clearly will last me 3 years. only about 3 months to go on that.

This race, it's a bike race? 30 mph average on a stage profile like that would not surprise me any. But I think you could keep up with a bike able to do around 35 mph for sure. To get that out of a typical 26" bike hub motor, you could run a 72v pack, but only 20 amps of power, so as to keep it milder on the batteries. Two 72v 20 ah packs would be 3000wh. You'd have 1500w of power that way. If you run a faster wind hub motor, then you could easily get about 32mph from 48v.

This bike for example, could easily do what you want. 48v 40 amps controller, and an old 5304 crystalyte motor on it. 2000w of power, so no hill phases it. It can easily carry 3000wh in the saddle bags. It will cruise at 33 mph easy, but slows of course at the end of a run.

So my point is this, perhaps some of your budget could include a wire feed welder? With some practice, you will free yourself from whatever Yuba or Clever cycles thinks you want, and GET what you want.

In the short run, you can still set up a stock 7 speed steel beach cruiser with a hub motor and battery able to do that run, immediately. Look for one with the rear rack welded on, like the huffy panama jack.

For rocky mountain grades, I later decided I really needed 20" wheel, so the next bike was designed for that, and to carry 48v 40 ah in the frame. So the next year, my welding project was this bike. The core frame of this one, was a very good vintage cromoly MTB. This bike is super slow, but able to climb any paved road highway in New Mexico, on 1000w max power. It's by far the most efficient e bike I have ever owned. Low rpm hub motor in 20". It just doesn't heat up much on hills. On the flat, it's so slow it has to be efficient. 18 mph max speed.


On the other hand,,, if you just wanted a good longtail e bike, without the 35 mph speed, then it's a no brainer to just snag a new longtail, from clever cycles, with the mid drive on it.
http://www.xtracycle.com/edgerunner-electric/

 

[ryan]

Thanks for your feedback. I know it's a tall order. But building bikes with challenging goals is part of the fun for me.

Where does the Race start? Which direction does it go around, clockwise, or counterclockwise.

I plotted the route: https://www.plotaroute.com/route/243264. It goes clockwise around the lake, starting (and ending) at Zephyr Cove Resort on the Nevada side in South Lake.

 

[ryan]

Thanks for your help dogman. I love the new 20" build! And the edgerunner looks fine, but I rode a $5k downhill bosch PAS middrive yesterday and while I was impressed with the technology, I was underwhelmed by the performance. If I haven't already been spoiled by ES and my very torquey, very quick builds, I would've been fine. But I think I'm ruined on stock ebikes for now.

There's a lot in what you said, but let me clarify one thing quick:

This race, it's a bike race?

Yes, it's a race. And the record is around 2:50 (Avg 25.5mph). BUT, I'm not really racing. I'm just in it for a "safer" ride around the lake while trying to build a bike that can accomplish the goal. Non-competitive racers are still timed. I think I'm welcome as a non-competitive racer, but who knows. I'll start later, or earlier and time myself if necessary.

I assume I'll be much slower than the peloton in the flats and downhills, but make up my time on the climbs. If I can do the big climbs near 20mph, I'll do just fine around 25-30mph the rest of the way.

I hear you on building my own bike, but right now I'm pretty sad about losing the bike I did spend so much time on. I want this ride to be more easily replaceable— to spend more time riding and less time building.

 

[ryan]

To fit Dogman's suggestion of 3000wh, and Alan's recommendation of Luna Cycles and to use 18650 packs, here are a couple of options for battery power.

1) 4x 72V11Ah 18650 pack — $549ea (via Luna Cycle) — $2200
This gets me 3300wh, and at 72V, a lot more top end speed.

2) 4x 52V20Ah 18650 pack — $630ea (via Luna Cycle) — $2500
This gets me 4100wh, at a more leisurely 52V.

The 72V is attractive for speed and form factor (I think I could fit them in the running boards again like my last build). But one more kwh for only a couple hundred more is attractive.

If I go mid-drive, the Tangent looks amazing. The BBSHD is also a contender, but I'm concerned about its power output. I watched a couple videos and am slightly concerned about the noise. I used to take my kids out on my 100lb bikes and join the lycra pelotons with much confusion. I fear the mid-drive would piss off my trail/road-mates.

If I go hub, where do I look these days? Is the Crystalyte TC3065 the way to go? Or have geared hubs started to gain traction here?

 

[ScooterMan101]

For that Race around the Lake, or any Race, or any Ride With Roadies,
You want a lighter weight bike, and smaller hub motor, and smaller battery pack, and higher pressure tires , at least 65 psi and up.

For taking the kids around , and going to the store, and a weekend day trip to the beach with the kids in a trailer , well then a heaver bike , bigger fatter wheels around 2 inch,
would be the bees knees.

With a $ 5k budget you could get/ have both bikes .

You can do that by buying a cheep bike for the Store/Kids/Trailer Pulling/ etc.

and

Getting more of a Race bike, or mountain bike that you put skinny/higher pressure tires on. etc. you can get good deals on used ones , as long as you know what you are doing.
By using the Same battery Pack on the Race Bike that you do on the heavy bike or in your case , one of the battery packs from the heavy bike, just use one pack one day and the second pack the other day to keep the cycles around the same for both packs, that way you can parallel the packs at any time.


What is getting more prevalent these days are lighter and lighter weight geared hub motors, ( less weight , less rotating mass , equals less wattage to go the same distance ) ,
I have run a Mac Motor and was and still very happy with it. it is 9.4 lbs. the highest I would go with these days for a 30 +/- a few mph bicycle .
Now I have 5 rides on a small 4.5 pound geared motor , ( Q100c CST ) on a bike that is stock 9 lbs lighter to begin with / no front suspension or suspension seat post , and I love it as much the powerful Mac, for speeds that it goes up to , around 23-24 mph. that is all it does on the flats with its speed wind , 201 rpm one.
there is talk of some improvements on the 6.6 pound Q 128 c CST, ( although it still will not have the power of the Mac )
People who have the heaver bikes and DD motors are happy, as one of them put it , you will be happy with any e-bike you build up,
So for your every day, locked to the bike rack at the store, going to the beach with the kids in the trailer, the heaver bike would be OK,

For that race , and any other race, riding with roadies, a quiet, under 10 lb, geared hub motor is most popular right now for good reason.
( I road my Mac at quiet 200 watt levels, and at much higher power ) However , with your budget you could , with buying the bike / bikes used have both a Mac, and smaller motor stable of -bikes.

 

[Alan B]

The BBSHD is very quiet, like a geared hubmotor, perhaps even quieter. Off bike you can't hear it, on bike I hear the chain more than the motor. It is a bike noise, and not loud at all. The Tangent is a mild screamer. It operates at high RPM where the BBSHD is much lower RPM.

For climbing the steep stuff efficiently the mid drive is excellent, as is a big hubmotor like a Cromotor or the other big 3+KW hubmotors like MXUS. Xlyte has fallen behind. The smaller hubmotors overheat on the steep climbs and don't operate efficiently at high torque levels.

The BBSHD integrated controller maxes out at 60V, don't consider above 14S 52V packs (58.8V full) for it. Gearing makes top speed, high voltages are not required. It is only a 1500W peak system, but it uses those watts very efficiently through the bike gearing.

It is much easier to install a BBSHD than building up custom wheels with hubmotors and having to mount big controllers on the frame and redo all the gears and braking to accommodate the hubmotor. The BBSHD has most everything in the one unit that quickly bolts up to most frames (check first, there's a thread on that, some frames are not very compatible). You retain all the rear gears and pick one of several available chainrings for the front. The cabling is neatly integrated and plugs together quickly. You only have to deal with battery mounting and wiring. You get to keep and use whatever heavy rear axle, wheel and brakes the bike comes with, or you can upgrade to the excellent hydraulic ebike brakes with integrated control switches for motor cutout, and there's a shift sensor cutout if you want that. For a really deluxe setup get a Rohloff rear IGH, they can handle the BBSHD power and allow you to shift while not moving and give a very wide gear ratio and even shift steps.

The big hubmotors in the rear make it hard to have many good pedal gears, and in the front it is hard to utilize that much torque on some surfaces and keep from damaging the forks, plus front suspension doesn't work. With the BBSHD the weight is centered, and the front (and possibly rear) suspensions work nicely.

You recall the Slacker hill trip that almost melted my hubmotor, and did melt at least one other. I made the same trip recently with the BBSHD on the RidgeRunner and it was barely warm, and I rode the whole way. The guy with me had to push up the steep stuff and his big hubmotor was very hot even with that. No comparison at all. The BBSHD will climb stuff so steep that the front wheel is coming up and I'm worried about falling backwards even with just pedal power, without overheating. Gearing makes the difference. The bike is much lighter than the hubmotor equivalent, and more bike-like and trail friendly. Beyond the Tahoe trip it will allow you to go places the hubmotor will not, both physically and politically. If you haven't looked at the RidgeRunner thread and my article on electricbike.com you might want to review them. The Cromotor is great but the weight gets way up there, about 3x the RidgeRunner. Even a modest hubmotor on a mountain bike weighs 50% more than the RidgeRunner with similar 1KWh battery. The geared hubmotors are about the same weight as the BBSHD and they have about the same power handling and do quite well, but at really low speeds they too become inefficient where the mid drive is still happy, and their weight distribution is not as centered on the bike. For a pavement commuter the hubmotor is excellent, not so much for an all-surface do-anything machine. So it depends on what you want and where you want to be able to go, of course. One of each is nice if you can do it.

I was going to put a geared hubmotor on my folding bike, but according to the simulator it will overheat before I can climb the grades in the Berkeley hills. So instead I will probably put a BBS02 on it, and it will easily climb them. That bike is too small for the torque of a BBSHD, it will not need that much power to wheelie and we don't really need that feature.

Regular hubmotors are great when the hills aren't too steep, but if they are steep then a big hubmotor is required to stay efficient, and the weight and power go way up, and it becomes very un bicycle like. Marin has some really steep stuff. You'll enjoy it more on a silent mid drive, and you'll get to enjoy more of it too.

 

[ryan]

My BBSHD with 52V and 20AH went 26 miles of hard fast riding to exhaustion. That was 25+ and 1800 feet of climbing. Three of those packs should do your ride. My newest pack is 52V 24AH, so I have a bit more margin.

Alan, I just read your BBSHD build article on Eric's site. Very impressive.

And I also just got caught up with your post above. Thanks so much. You're making a very good case for the BBSHD. And I remember that Marin hill very well. I stayed up most of the night prepping 72V20Ah of Headways for the climb only to find some of the cells were duds. So very disappointing. I'm looking forward to letting Luna Cycles take care of my pack building (or maybe Ilia at ebikessf, I reached out to him as well.)

Assuming I'm on a 52V system and the IGH you (and Eric) recommend, what should I expect in terms of speed? Would I be able to maintain 25mph for 3 hours, including the 900ft climb over emerald bay? Would I be able to get above 30mph on flats?

 

[Alan B]

With 1500W your speed on inclines will be determined by the system weight and gradient and what the 1500W can lift, assuming you have the gearing to fully load the motor. It is not going to be as fast as 6kw pumped into a 3kw hubmotor. The simulator can show you what 1500W can do. I find 20-25 mph on moderate grades, less when it gets really steep. That's where the Borg really shines, but the power consumed is more than 1500.

I have studied the Rohloff but haven't used one so Eric and others with real experience should be consulted for data there. Wheel size also matters as part of the gearing.

On downhills and flats the speed is determined by air resistance and gearing. My system runs out around 30 but I think I'm running out of gearing, not hitting full power. I don't like to run below 14T on the cluster to avoid rapid chain and cog wear. The IGH should not have that problem. California law now now allows 28 mph so it is just about right.

You are going to be a bit heavy on this ride due to all the battery weight. That will affect climbs and flat speed.

I also run knobby and fairly wide tires so have not optimized there at all.

One thing I forgot to mention earlier - changing tires on a hubmotor is really no fun with torque arms and a really heavy wheel, on a mid drive it is just like any other bike. You can even use quick release hubs.

Anyway, give it some thought. You have a lot of options here. Have fun and choose a ride that meets lots of your goals!

 

[dogman dan]

Really,, except for the actual race, I'd have to say mid drive on any long bike for the win. For packing kids and cargo around a town with some serious hills.

Have you looked here, at stokemonkey kits? http://www.ebikes.ca/shop/conversion-kits/all-stoked.html Put one on a Yuba?

But for that race, or just for a faster bike, a big fat hub motor, 72v, and 20" wheel. So you can cruise at 35mph when you want. That will take care of all that shit about low rpm inefficiency, and heating up on hills. John in CR has had it right for years. You can get that 20" rear wheel in a long bike now, you don't have to build it.

Put a big fat motor like the muxus or leaf, on this. http://clevercycles.com/2016-xtracycle-edgerunner-cargo-bike-24d

I just built my bikes for the fun of it, and because I have a bike junkyard, and a $100 welder was cheaper than a $2000 bike.

And, you can put the BB on that bike, but I'd be more inclined to stick with 26" wheel with the mid drive.

 

[tln]

With 1500W your speed on inclines will be determined by the system weight and gradient and what the 1500W can lift, assuming you have the gearing to fully load the motor. It is not going to be as fast as 6kw pumped into a 3kw hubmotor. The simulator can show you what 1500W can do. I find 20-25 mph on moderate grades, less when it gets really steep. That's where the Borg really shines, but the power consumed is more than 1500.

Is the BBSHD really capped at 1500W? The BBS02 is rated at 750W but pulls 26A for a maximum of 1300W for me on 12s (fresh off charger).
I think it would pull more watts on 14s. So I'd have thought the true max for the BBSHD was higher.

WRT possible geared speed this bike calc may help. This is a typical range for a MTB cassette, and the front 42-48 will show the BBSHD typical chainring sizes.

http://www.bikecalc.com/speed_at_cadence

 

[ryan]

Put a big fat motor like the muxus or leaf, on this. http://clevercycles.com/2016-xtracycle-edgerunner-cargo-bike-24d

Wow. The Edgerunner looks nice, but why o why is it twice as expensive as a Mundo? Perhaps that's why there's no used ones, anywhere.