Another n00b

[simonov]

Hello everyone.

I'm of course new to this site, new to e-bikes and even sort of new to bicycling (I haven't done it in a long time). I'd like to build an e-bike as a winter project, and while I have read the FAQs and have a general idea of what I intend to do, I still have some lingering questions and in any case I thought I'd get the advice of experienced folks as to how, exactly, to begin. I've seen how you guys appear to enjoy sharing your knowledge with n00bs. I'll try not to be too n00by around here, but basically I am starting from zero (though I have read the FAQs).

I am 57 years old and just stated (like this week!) bicycling to work (7½ miles each way). What happened is I bought a new bicycle for my partner for her birthday this year, and that got me to pull my 2004 Giant Sedona out of mothballs and do some riding around of my own. My typical exercise is hiking and mountaineering, but for various reason I haven't done much of that lately. I discovered I really enjoy the bicycle commute, though there is a hill involved, and that's what got me interested in ebikes. I am a tinkerer, so doing a conversion makes a lot of sense, especially as I have (I think, more on this later) a decent donor in the form of the old Sedona. I'm nearly six and a half feet tall and the Sedona is too small for serious pedaling:



I decided if I really got into bicycling I'd buy a new larger bicycle, but in the meantime the Sedona works okay and maybe I can electrify it.

I don't ride in the dark, so my bicycle commuting season will end in November with Daylight Savings (if not sooner, depending on when it gets light or dark around here). That makes winter a perfect time to work out what I need to do and then execute and test the conversion.

As I said I read the FAQs and I believe I have decided on a DD rear hub set-up (for its simplicity and also to get regen); with whatever compatible controller is recommended by the vendor (I am liking Grin Technologies these days, but a US-based vendor would be cool too); and a LiFePo4 battery so I don't have to worry about burning down the house (or office). The FAQs are almost good enough you could spec a system from them exclusively, without asking questions, but I feel my requirements are slightly different from the typical Endless Sphere contributor, so I might get away with less system than the FAQs seem to indicate.

Riding style

I have no desire at all to ride at high speeds. I would like to pedal, so I guess I'm looking for some kind of pedal assist. An electric will simply make the daily commute less fatiguing than it otherwise might be. The main requirement I have for the system is the hill at the end of the ride home. I really dislike climbing that hill, especially at the end of a long day at work. I've worked out the hill slope:

Pembroke Street
rise: 76 feet
run: 2,623 feet
slope: 3%

Parkway Drive
rise: 34 feet
run: 519 feet
slope: 7%

Combined
rise: 110 feet
run: 3,142 feet
slope: 4%

Okay, that might not look like much, but it takes a lot of the fun out of the ride home. On the other hand, that's all the hill climbing I will probably ever need to do. The rest of my route (and most of the rest of Reno) is pretty flat (I stay off the streets by riding along the Truckee River bike path as much as possible).

Donor bike

Given my relatively mild requirements, I'm hoping I can get away with a more lightweight set-up than a higher performance rider would require, and so my aluminum Giant Sedona with rim brakes would be an acceptable donor. That's one of the main things I'd like to get answered here.

If it's simply not practical, I have many other options. Every year hundreds, maybe thousands of bicycles are abandoned at the Burning Man festival, and they are typically donated to Reno Bike Project or the Kiwanis Club, so it's easy to find donor bikes (though of course I am unlikely to find anything especially fancy or exotic). But I'd like to use the Sedona if possible.

In a nutshell:

General requirements: Daily 15 mile commute (7½ miles each way), mostly flat, with under a mile of 4% average slope on the ride home. No high speeds. Some pedal assist and regen.

Type of system: Direct drive rear hub, sized for the above usage (I understand my requirements sort of indicate a simpler mid-motor setup, but you guys have sold me on hubs, and I'm also not interested in shifting gears all the time, but I can be convinced otherwise). The lighter the better, based on my requirements.

Battery: LiFePo4. Can have chargers at home and at the office.

Proposed donor: 2004 Giant Sedona, aluminum frame, rim brakes, grip shifters (any or all three of these could be issues, which is why I wanted to bounce them off you guys).

Preferred vendor(s): One of the reasons I'm doing a conversion is to save a few dollars over buying a new bicycle, but I have no interest in buying the cheapest parts just because they are the cheapest. My requirements probably don't justify the highest end systems, but I don't want crap, either, just because it's cheap.

If I could get some pointers as to how to size the system I need, that would help get me going. Also if any of my assumptions are way off base, I'd love to hear about it.

Thanks for any assistance,

Mitch in Reno

 

[flat tire]

TDSZ2 torque sensing mid drive. Gear down for the climbs and no problem.

 

[motomech]

There probably has not anyone who has done as much for the sport/past-time of ebikes than Grin, they certainly have been helpful to me. But having said that, trying to save a few bucks on the donor bike and then buying the system from Ebike CA makes little economical sense. If you were building a advanced ebike w/ high-end components, then maybe Grin would be the place to look to.
But, as a Noobie building for a commute that doesn't seem to place many demands on the ebike, you don't need anything more than a basic hub motor kit off Ebay.

The Donor Bike;

IMO, the best value in Ebiking are used mountain bikes. For those who live in an area where mountain biking is popular (And you do), Craigslist is full of fantastic deals. The equipment has advanced so rapidly in the last few years, that MX bikes, say from 2000 to 2010 w/ 26" whl.s are considered too heavy and obsolete. Fortunately for us, weight when using motor power is of little concern and in general, 26 inch is the best size for a hub motor install.
Add to this the fact that many folks buy mountain bikes, try them out a couple of times, realize how much work it is and park them in their garage. All my donor bikes were picked up in mint cond for less than half than the MSRP. Nice bikes with disc brk.s and full suspension(things that many here will say are not needed, yet, there is little record of anyone saying they regret starting w/ them). My Rocky Mountain is a 2003 (bought in 2006) and although the power system has been rebuilt/revised several times, I've had to do little to the bike itself. It pays to start w/ a quality donor bike.
It will be easier to find an XLG frame size when looking for mountain bikes than when looking at the other styles.

The Battery;

I'm not sure what got you thinking about LiFePo4, but I believe Li-Ion offers less weight for the capacity and safe "plug and play" charging. In fact, using a crude rule of thumb of 1 1/2 miles for one Ah of capacity, a 10 to 15 Ah pack would eliminate the need to charge at work. Maybe a quick "top-off at lunch might be the best compromise. The battery is the place to put your money, look for one w/ name brand cells, like Panasonic.

I don't ride in the dark, so my bicycle commuting season will end in November with Daylight Savings (if not sooner, depending on when it gets light or dark around here). That makes winter a perfect time to work out what I need to do and then execute and test the conversion.

Before I retired and moved the Mexico, I lived in Tucson, a city that has a lot in common w/ Vegas. And I will venture that as you enjoy your ebike and look for reasons to ride it, you will be riding at nite. It's the best time during the summer. And as far as summer vs. winter, day-time riding into late fall and starting again in early spring is much more enjoyable than riding June thru Sept. When it's a little chilly, one pedals harder, when it's 100 F plus, one stops pedaling!

Another thing they have in common are the Bane of Ebikers, Goats-head thorns. As the monsoons fill the bike lanes w/ sand, these little buggers will start studding the thread of your tires. I think you will find that "flat-resistant" tires (w/ a Kevlar band) and extra thick tubes will be a must have.

Motor DD vs Geared;

When I started 8 years ago, I wanted to go stealth and the pie-pan size of a DD motor didn't seem very stealthy to me. As it turned out, people didn't really notice that it's an ebike, especially back then, and being stealthy wasn't important. Up until several years ago when the rules were changed for multi-use paths. Then my "assist-bike, w/ it mini geared motor, no bigger than the cassette and it's sm. batteries became the better ebike for MU paths than my 2WD. W/ it's larger motors and lot's of batteries, it just screams Ebike. I would suggest you look at the MS path rules w/ an eye as to how they might change in the future.
I also like the way a geared motor free wheels, as often I would adopt a "point and shoot" style of riding in town. Basiclly, pedal like Hell from the light and then coast to the next light. I suspect that the "cogging" resistance of a DD motor when coasting is over-blown, but one thing I'm sure of is the "regen" feature is over-rated. You won't gain any appreciable range from regen, especially in a place as flat as Vegas.

For an ebike that tops out in the 22 to 25 mph range, that needs the least "muss and fuss", I've kind of settled on these formulas;

Mountain bikes w/ 26" wheel, space in the frame triangle for batteries are highly desired.

Low-power Mini-geared motor on 52 Volts w/ a low-speed range (201) motor, Controller around 20 Amps. Top speed 21 to 23 mph w/ decent hill climbing ability.

Mid-power Mini-motor up to the larger 5 Kg. geared motor in the mid-speed range (260) on 48 or 52 Volts. Controller 20 to 30 Amps and a top speed up to 25 Mph. This set-up would have little problem w/ any hills you will encounter.

 

[MadRhino]

Welcome to ES

I suggest that you buy a bigger bike. A small bike may be fun for some purpose but once motorized, the short wheelbase does translate in a lack of stability.

 

[E-HP]

If I could get some pointers as to how to size the system I need, that would help get me going. Also if any of my assumptions are way off base, I'd love to hear about it.

Thanks for any assistance,

Mitch in Reno

My first donor bike was very similar to yours and worked fine. But, I switched to another frame because I wanted disc brakes. The linear pull brakes were sufficient, but the discs perform way above the minimum threshold, so you may want to consider that.

I got the cheapest 1000w rear hub kit on ebay, chucked the controller, and bought a decent sine wave controller and display. It will meet your criteria, easily.

You don't need a lot of battery capacity to meet your requirements, but you'll want to ride a lot longer with an ebike. I've gone out several times for a short ride, and end up riding 30+ miles. I would get a battery with 1) the best cells available, and 2) more capacity than you anticipate needing. (this is your biggest investment, so you want it to be up to the task)

 

[markz]

I think the rider of that bicycle is well into the 6'4"+ club!
What would suit that rider, IMHO is a Townie Electra cruiser, feet forward bike, 3x7 like the Townie Electra 21D. Used prices would be $350-400cdn which is like $250-300usd.
Leafbike/Leafmotor 1500W kit with a 48V controller/battery.

 

[dogman dan]

Ping battery for a good lifepo4. Get a 48v 15 ah.

Nothing wrong with a good quality 48v grin kit. You plan to commute for a long time, despite the lack of a good bike this month. But you can ride the Sedona for awhile.

Re the bike, a good 7 speed beach cruiser will do. The townies are real good bikes. But any beach cruiser with 7 speeds will work fine for you. They work great for commuters. Extend the seat post if you have to, the steel ones can have the bottom end cut off, and stack on another, secured with a bolt. The big sweep handlebars can be set to reach your taller hand position, and or get a tall stem like you have on the Sedona.

 

[simonov]

Thank you so much for all the specific advice. However, it looks like this very first reply from flat tire is going to work for me:

TDSZ2 torque sensing mid drive. Gear down for the climbs and no problem.

See, there was nothing about torque sensing in the FAQs! If I understand the technology correctly, it simply offers assist when I am pedaling, and has no throttle. Like giving me bionic legs. This sounds like exactly what I want, and it's dead simple to set up as well.

I don't mind shifting gears, after all, I do it all the time when riding without a motor, but I was kind of put off by the idea of having to shift to manage the motor speed. But the torque sensing mid drive sounds like it can be run pretty much like an unmotorized bike.

I don't mind spending a few dollars to simply things, and the FAQs make it pretty clear that the various LiPo batteries are dangerous to charge unattended, while LiFePo4 is not. I used to run RC cars and was always careful to charge the batteries out on the back patio. Not a big deal for a toy you use maybe once a month, but I'm going to be charging the bike every night and possibly every day at the office. LiFePo4 provides ease of use and peace of mind.

Please correct me if I'm wrong.

I understand the donor bike is not ideal (ha, just look at the photo!), but it's the bike I have and since I won't keep it long term for unassisted riding, I might as well extend its usefulness by electrifying it. Except for the mismatch in size, it seems to be a very nice all-around bike (if I am any judge of such things, and I'm probably not).

From my reading here on Endless Sphere, I'm almost certain this will not be my last electric bicycle, just a good start. We have these hills and mountains around here that are begging to be explored by a powered two-wheeled vehicle, and while I've been considering getting a motorcycle for this purpose, you guys have got me seriously thinking about building up a bespoke off-road e-bike with motorcycle wheels. But baby steps first.

I still have a lot to learn about bicycling in general. As mentioned, goatheads are a real problem here in Reno (so I'm told), especially on the Truckee River path. Incredibly, I am running the original tires and tubes from 2004 and I've never had a puncture. Let's see if that record can last through the riding season that ends in November. During the winter I expect to change the tubes and tires.

Before I retired and moved the Mexico, I lived in Tucson, a city that has a lot in common w/ Vegas.
. . .
You won't gain any appreciable range from regen, especially in a place as flat as Vegas.

Thank you for the long and well thought-out reply. Some very useful information there. But now I really think I'm going to start with a torque-sending mid drive.

However, I'd like to make this a teaching opportunity for you and everyone else on Endless Sphere, especially as so many members are from outside the US.

Geography lesson!

Nevada is 110,567 square miles in area (286,367 square kilometers). Las Vegas and Reno are 463 road miles apart via the shortest route (745 km), about a seven hour drive (I make this drive once a year). Las Vegas and Reno are twice as far apart as Las Vegas and Los Angeles.

Las Vegas is a suburban sprawl of two million people over hundreds of square miles of desert. Reno and sister city Sparks have fewer than half a million people, mostly nestled in a high elevation valley between the Virginia Range and the Sierra Nevada. There is a still-wild river running through Reno and two large and beautiful natural lakes within an hour's drive. Reno has four seasons, and while the summers can be hot, the temperature drops 30 degrees (F) every night; it's an outdoorsman's paradise. In Las Vegas, no one (except mad dogs and Englishmen) goes outside in the summer except in air conditioned vehicles.

I'm posting all this because I've discovered it is actually very, very common for people to confuse Reno with Las Vegas, or to assume Reno is a suburb of Las Vegas. We (my employees and I, who moved here three years ago from LA) hear it all the time. Even a lot of people in Vegas aren't really sure where Reno is, or even if it really exists.

 

[thundercamel]

My bike is an aluminum frame with v-brakes as well. I did happen to get an upgraded suspension fork that came with a disk brake mount, but only because the original fork was garbage. You'll be fine for now, and you can always put it back to stock if you need to.

 

[flat tire]

Yes, torque sensing is like having bionic legs. It's the biking you've always known but better.

 

[simonov]

UPDATE: I got the 750W TSDZ2 from Electrify Bike with 52v 40 amp 14AH Panasonic GA Super-Shark back in May 2020. It cut my 45 minute commute down to a half hour, and I no longer had to dread that final hillclimb at the end of the day. Not only that, but it gets windy here in Reno, and some days the wind was harder going than the hill. The only time I ever set the power to 5 was in a stiff wind (I normally keep it set at 3 and maybe 4 on a hill). I never even installed the throttle, I always use pedal assist.



However, I soon moved into the city and now my commute is only 6 miles round trip instead of 15 miles, and no really challenging hills. Still, I love my e-bike and evangelize to anyone who will listen. My riding commute takes 12 minutes, the same as in a car. The motor still makes riding easier, and what few hills I do encounter are no problem. Plus I'm still getting decent exercise.

All the pedal assist really does is make me go faster than I would otherwise, and makes hill-climbing easier. I'm still working my legs. It's hard to describe this to people and unfortunately not many of my friends can ride my bike to try it out since it's too big for most people I know.

As it gets warmer here, I am thinking about new projects. I'd like to build bikes for one or two of my friends. I like the mid-drive set-up, but I think my next project will be a Bafang and battery from Luna, just because (I'm very happy with my TSDZ2).

But I also want to build a stealthy off-road bike, not necessarily a mountain bike,* using a hub motor, again just because. Hub motors kind of confuse me, since I am not sure how you regulate the power with the non-geared versions. I need to do more reading up. And I'm disappointed Luna doesn't offer any.


* We have a lot of fire roads and jeep tracks around here that are unregulated and ideal for off-road biking. I have no interest in single-track since trails are shared with hikers and dogs (like me and mine) and the single-track bikers I see seems to spend more time avoiding the other trail users than riding. Doesn't look like as much fun as just getting onto a jeep track and letting rip. So what I really need is a rugged bike with a fatter tire for gravel, ruts and snow. The plan is to pick up a donor at the Kiwanis used bike place.

 

[thundercamel]

Commuting on the ebike is nice, right? I've built exclusively direct drive hub motors for myself and friends/family, mostly for the sake of reliability. The conversion kits come with a motor controller (the Remote Control crowd calls them ESC for Electronic Speed Controller) that determines how much power goes to the motor.

Each of my bikes has a throttle on the handlebar, that I have to feather while riding, which can get tiring. I try to pedal what I can, and only use a bit of throttle to maintain my target speed for the trip. The conversion kits also come with a cheap cadence based PAS - Pedal Assist Sensor, which don't work for me because they seem to just go full throttle when they detect any pedaling.

There are nice torque sensing bottom brackets that can interface with a Cycle Analyst, which then puts out a throttle signal to the motor controller. I hope to have that set up one day.

 

[simonov]

So do DD hubs require use of the throttle to maintain speed/torque? I don't think I would like that.

I know geared hubs are an option. I understand they are noisy and relatively complicated and therefore subject to breakage.

I'm aware my TSDZ2 has some components that will probably break eventually. But I don't bash my bike the way a lot of riders do, so I'll see how long it lasts.

 

[dogman dan]

Looks like you never fixed the bike doesn't fit you problem though. Depending on your seatpost size, you need to either get a longer seat post, or if its one of the smaller diameter posts, you can get two cheap steel seat posts from junk bikes, and then make a long post from the two.

You cut the bottom end off one post if its rounded off any, then stuff it on top of the other seat post. Weld it, or if you don't weld, drill a hole and put a screw in it to secure the posts into one tall post.

Now your handlebars are waaaaaay too low. Easy fix, BMX handlebars with a tall rise to them. You might need a shim to secure in the handlebar stem. BMX bars usually have a smaller diameter. A scrap of aluminum about 1 mm thick works the trick.

For your new bike of course,,, get an XL frame.

 

[thundercamel]

So do DD hubs require use of the throttle to maintain speed/torque? I don't think I would like that.

I know geared hubs are an option. I understand they are noisy and relatively complicated and therefore subject to breakage.

Both a geared hub and direct drive hub would need something to modulate the throttle to match your speed and pedaling effort. They both usually use an external motor controller as well, and those controllers don't know or care whether the hub is geared or direct drive. Some of the controllers do a better job at modulating throttle with the cheap cadence magnet wheel pedal sensors, and people get them to work well enough.

As far as I know, the TSDZ2 and BBS-02 and BBS-HD come with the motor controllers built in, and also include a nice torque sensing pedal assist system.

 

[simonov]

Looks like you never fixed the bike doesn't fit you problem though. Depending on your seatpost size, you need to either get a longer seat post, or if its one of the smaller diameter posts, you can get two cheap steel seat posts from junk bikes, and then make a long post from the two.

The bike fits me okay. I raised the seatpost so that my legs are now straight at full extension, and raised the handlebar post as far as it will go (not much). I just love the hell out of my bike, because it's so tough and useful and utilitarian.

I do intend to find the biggest bike I can for my next one.

Both a geared hub and direct drive hub would need something to modulate the throttle to match your speed and pedaling effort. They both usually use an external motor controller as well, and those controllers don't know or care whether the hub is geared or direct drive. Some of the controllers do a better job at modulating throttle with the cheap cadence magnet wheel pedal sensors, and people get them to work well enough.

I kind of wanted to fiddle around with hub systems, but the more I learn about them the happier I am with the mid-mount motors. I am pretty certain my next project (for myself or a friend) will be with a BBSHD.

I believe I will someday fit a powerful hub motor to a throttle-driven off-road tadpole, but that's a ways off.

 

[dogman dan]

Oh cool, I thought maybe you still had too short a seat. For me, I needed the bars taller to ride long distances.

Bike fit matters less the shorter the ride.

 

[E-HP]

As far as I know, the TSDZ2 and BBS-02 and BBS-HD come with the motor controllers built in, and also include a nice torque sensing pedal assist system.

minor correction. only the tsdz2 has a torque sensing pas. i believe the bbs units have cadence. the higher end bafangs do have torque based though.

 

[simonov]

Bike fit matters less the shorter the ride.

Indeed. Most of my rides are pretty short these days, about three miles per segment. I gave up the padded underwear for my work commutes.

Sometimes I go on longer rides, for recreation. The biggest problem I have then is in my hands: my fingers tingle and fall asleep, I guess because of the weight I'm putting on them. I'll ask about that the next time I shop for another bike.