Recommendations on first e-bike upgrade

sryland

10 mW
Joined
Jan 23, 2018
Messages
24
Location
Spanish Fork, UT, USA
Hi all,

I posted earlier about ideas for an ebike upgrade, and received a lot of really great help that steered me in the right direction, so I went away and did a lot more research, and I'm hoping you can get me through the final steps. I'll try to be concise.

BACKGROUND: I want to quit my car as much as possible, but my commute to school is 26 miles round trip, and has a couple of hills - low grade but long. I don't mind it too much, but would love a bit of assistance so I can cut 15 minutes off the 75 minute trip and not get wrecked on the hills. I weigh 250 pounds, so those hills can hurt!

At first I was looking at a BBS02, but after advice it seems better to get a hub motor for simplicity and ease on the drive train. The geared hub motor seems like a good fit for me - I can just ride normally, and kick in the motor when I need it, especially on the hills.

I love what you guys do, DIY-wise, but I really want to get a simple system that just works. I call it the Toyota Corolla philosophy - nothing too flashy or fast, but reliable, even if I have to pay a bit more. For example, I'd like to get a solid battery pack from a reputable dealer that I don't have to worry about building a bunker for...

Here's what I am learning towards:
Donor bike: Giant Roam XL Hybrid with 700c wheels (love this bike)
From em3ev: https://em3ev.com/shop/upgrade-mac-kit-with-4750v-battery-1500w-max/ (a lot of you recommended this dealer)
Motor - Upgrade Mac Ebike Kit with 47/50V (25A Max) Battery Option, 10T winding (1500W Max) - $270.00
Controller - 6 fet 3077 (36-52V, 25A) - $60
Battery - 47V (13S4P) Preditor L 13.6AH MJ1 - $429
Charger - 54.6V 5A Charger w 90/100% switch - $60
Alex DM24 Rim and Spokes - $45
Torque Arm - Rear Rev4 - $38
CA3 - $130 (Is there a cheaper option? really just want to know battery usage)
Thumb throttle and cruise control - $13
Mechanical ebrakes - $6
Freewheel - 8 speed DNP (11t) - $22
Total: $1,073

How does this look to your expert eyes? Will this get me set up with a solid, reliable motor that meets my commuter needs? Are there any improvements you would suggest, or even better, savings to help me get authorization from my significant other?

Thanks again for your help!
 
sryland said:
I want to quit my car as much as possible.
Thank you! Nothing worse then helping destroy God's everlasting covenant by contributing to global warming. My 2's :wink:
......The geared hub motor seems like a good fit for me - I can just ride normally, and kick in the motor when I need it, especially on the hills.

Realize that e-bikes are heavy and just riding them around, geared hub motor not withstanding, when you put a motor on a bike and then add the batteries, it gets heavy.

I love what you guys do, DIY-wise,.....
Thank you! I would take a bow but that might seem prideful. I will leave that up to some one else around here.

..... reliable......
I have over 12,000 miles on my Chinese yescomusa motor. Others on this board have more miles on theirs then me. The point being DD hub motors last a long time.

I'd like to get a solid battery pack from a reputable dealer that I don't have to worry about building a bunker for...
That often also is a function of the type of battery chemistry you use. I use LiFePO4 specifically for it's low volatility. However, it has a low C rating and is big and heavy.

Here's what I am learning towards:
Donor bike: Giant Roam XL Hybrid with 700c wheels (love this bike)
Do you mean the XR? The XR's seem to have a big triangle. I always recommend putting your batteries and controller in the triangle if you can for proper weight distribution. The bike balances better that way.

However 700c wheels won't last long under the weight of you and the motor and batteries. The rims might take it, but the tires will wear out fast. Some around here love their fat tires, 2.5 inch or so, but in the city I prefer 1.5 inch tires. For me they have the cross of slim tires for agile movement and durability of roads where anything can happen to be in the road, pot holes ,nails, glass, palm tree fronds,.....and I am not joking about hitting palm tree fronds, they are like hitting a 4x6 or ladder or something big. I once hit one riding my road bike and it directed my front wheel straight into the curb which unloaded me on to the sidewalk. That one hurt!

I perfer bigger tires then 700c

CA3 - $130 (Is there a cheaper option? really just want to know battery usage)
The CA does a lot of cool stuff, If you want one, get one, however the cheapest way is to not use anything and ride by the seat of you pants. That's what I do. However, I know by putting an rc watt meter on my pack at charging how many watt hours my pack can deliver. I also know that around here I use about 27wh per mile. I check the miles I will need to go that day and multiply that by 27 to see if it exceeds my total watt hours capacity of my battery pack. If I will not be able to go the round trip on my available watt hours, I bring a charger with me and charge somewhere.

The second cheapest way is an RC watt meter. The final option (if not the first option) is the CA which is the gold standard of watt meters.

Anyway that is what I think.

:D
 
You have a good ebike kit there. But I’d recommend a bigger 14s battery if you can-the extra volts make a bigger difference than expected due to the current drop, less heat, more efficiency. Small percentages make quite a difference. And the bigger the battery the less it will be stressed and longer it will last. You may want to check out the Samsung 33g cells if you are not throwing big watts into the motor and want price/longevity. I have a 32mile trip using the Em3ev 14s rectangle pack with that cell charged to 85% discharged to 30%.

As mentioned the bike itself could be improved-I favour good suspension used bikes. On yours a thudbuster seatpost is a good idea.

There’s always an upgrade option....battery is probably the most critical thing to get right.
 
Looks about perfect. The battery will be big enough for one way, but a 15 ah (13s-48v) would work better in cold weather, and when its more than a few years old. You will have less capacity on a really cold day, but you can get there on less by riding slower in winter. If really cold, slower is also warmer, so that can work out ok.

You will have to charge to get home from work or school though. If that is not possible, you need at least a 20 ah, and a slower ride home, or possibly a charging stop someplace on the way home.

My commute was 15 miles one way, and all uphill home. I used 60% to get to work downhill, and needed every bit of the 48v 15 ah to get home and still have some reserve left. Best to discharge it to 90% daily, than to 100%.

If you go up and down hills, then it pretty much evens out for battery usage compared to flat, unless you motor hard to go down fast as possible.

When I started e commuting to work, I had 26 thou on charge cards, and a car expected to last about a year longer. I made that car last till the cards were paid off, in 4 years, simply by driving it two days a week instead of 7. It was not really gas money that was killing me at the time, it was car repairs. I got in that pickle by blowing my money on hot air balloon flying. Lots of that debt was repairs on the truck that chased the balloon, which costed out at about 2 bucks a mile. The old car was costing about a buck a mile. 25 cents a mile for the e bike left me about 10 bucks a day more to put towards paying down those debts, along with every other penny I had.

Scraping off that flying debt, along with some other planning we did 20 years ago, allowed me to retire at 59, vs working till 67 when I could get max SS.
 
e-beach said:
However 700c wheels won't last long under the weight of you and the motor and batteries. The rims might take it, but the tires will wear out fast. Some around here love their fat tires, 2.5 inch or so, but in the city I prefer 1.5 inch tires. For me they have the cross of slim tires for agile movement and durability of roads where anything can happen to be in the road, pot holes ,nails, glass, palm tree fronds,.....and I am not joking about hitting palm tree fronds, they are like hitting a 4x6 or ladder or something big. I once hit one riding my road bike and it directed my front wheel straight into the curb which unloaded me on to the sidewalk. That one hurt!

I perfer bigger tires then 700c

When you say bigger, do you mean wider? 700c is already pretty big. When I said XL, that was just the bike size.

It does have a big triangle, where I intend to store the battery.

I feel you with the palm fronds - I grew up in Australia and those things can be surprisingly lethal and tough, despite looking like innocent branches.
 
Tats said:
As mentioned the bike itself could be improved-I favour good suspension used bikes. On yours a thudbuster seatpost is a good idea.

There’s always an upgrade option....battery is probably the most critical thing to get right.

A seatpost may be a good idea. I don't like full suspension very much, just because I want to ride it as per normal as much as possible, and want to keep my triangle space in the middle. Either way, I love my bike, so don't want to change it! :)

I'm hearing the tips on batteries. My intention is to try and ride unassisted a lot of the time - especially as I have a lot of gradual downhills and flats. I know the motor and battery will add weight but I'm with my 250 pound body the ratio increase isn't as pronounced.

This is what my route to school looks like: https://www.google.com/maps/dir/135...0x874d973f71ea1591:0x4392dd221bbc63c9!1m0!3e1

Obviously home would be the reverse and a lot more effort, but the ride there isn't too bad. Is it too optimistic to hope that I can just engage the motor in the uphills and use the battery I originally picked out - or is it just better for longevity to spring for an even better one anyway? (I can charge at school as well, I have a private desk I can use).
 
dogman dan said:
Looks about perfect. The battery will be big enough for one way, but a 15 ah (13s-48v) would work better in cold weather, and when its more than a few years old. You will have less capacity on a really cold day, but you can get there on less by riding slower in winter. If really cold, slower is also warmer, so that can work out ok.

You will have to charge to get home from work or school though. If that is not possible, you need at least a 20 ah, and a slower ride home, or possibly a charging stop someplace on the way home.

My commute was 15 miles one way, and all uphill home. I used 60% to get to work downhill, and needed every bit of the 48v 15 ah to get home and still have some reserve left. Best to discharge it to 90% daily, than to 100%.

If you go up and down hills, then it pretty much evens out for battery usage compared to flat, unless you motor hard to go down fast as possible.

When I started e commuting to work, I had 26 thou on charge cards, and a car expected to last about a year longer. I made that car last till the cards were paid off, in 4 years, simply by driving it two days a week instead of 7. It was not really gas money that was killing me at the time, it was car repairs. I got in that pickle by blowing my money on hot air balloon flying. Lots of that debt was repairs on the truck that chased the balloon, which costed out at about 2 bucks a mile. The old car was costing about a buck a mile. 25 cents a mile for the e bike left me about 10 bucks a day more to put towards paying down those debts, along with every other penny I had.

Scraping off that flying debt, along with some other planning we did 20 years ago, allowed me to retire at 59, vs working till 67 when I could get max SS.

This is an inspiring story. I mean, it's cool that you had such an interesting pastime, but also using an ebike to save so much money and retire early. I've got a lot of miles ahead of me (hopefully), and hoping to save some money and also get a bit more exercise. Utah is such a car-based state, and I miss being outside. I feel like I just move from box to box all day.
 
sryland said:
A seatpost may be a good idea.
I ride with a spring loaded seat post. It helps some times and I love it for that, but they do ware out. As a reference, I weigh 197lbs. I go through one every couple or years or so.

I'm hearing the tips on batteries. My intention is to try and ride unassisted a lot of the time - especially as I have a lot of gradual downhills and flats. I know the motor and battery will add weight but I'm with my 250 pound body the ratio increase isn't as pronounced.

The weight is more then you are thinking. It is dead weight and you will feel it when you are only pedaling. I highly recommend getting a bike for your e-bike conversion and another one for just pedaling around when you feel like it.

Obviously home would be the reverse and a lot more effort, but the ride there isn't too bad. Is it too optimistic to hope that I can just engage the motor in the uphills and use the battery I originally picked out - or is it just better for longevity to spring for an even better one anyway? (I can charge at school as well, I have a private desk I can use).

Investing in a battery with a larger capacity will save you from that uncomfortable day when you hit LVC. On that day you will wish you got the bigger battery. It doesn't happen to me often, maybe once a year. Usually when I am forced to unexpectedly go farther then I intended, like something comes up at work and I didn't bring a charger that day.

:D
 
Take a look at my build: https://endless-sphere.com/forums/viewtopic.php?f=6&t=88000&p=1284485#p1284485

Seems like the route you're going except with a rear motor...

I'd go with this battery: https://www.aliexpress.com/store/product/US-EU-Free-Tax-Electric-Bicycle-dolphin-battery-52V-1000W-Ebike-motor-use-14S4P-NCR18650PF-cells/1178407_32739980524.html?spm=2114.12010612.0.0.43f5e1c0ezxLci - during the fall it was running for $355 with free shipping, can verify they are PF cells, no voltage sag like my 48V pack.

Definitely get the wheel professionally trued laterally and radially before install...it seemed true when I got it, but after having this done it changed my top speed by 1mph. :shock:

I wouldn't recommend the electric cutoff brakes...they started shorting out within 3 months making the motor cut out randomly, took forever to track down. Been riding with no brake cutoff since and have never had a close call or OOPS moment.

If you just want battery usage, get one of these: https://www.ebay.com/itm/FT08-RC-150A-Hight-Precision-Watt-Meter-and-Power-Analyzer-w-Backlight-LCD/141413493299?epid=1733616744&hash=item20ece6aa33:g:WKYAAOSwQItUHQkM - $12 and will show you the essentials: voltage left, watt/hrs, amp hours, amp draw...if you want to know your speed, just use a gps speedometer app on your phone and get a handlebar mount.

I tried the thumb throttle...thumb gets sore keeping it pinned for a long time. I use this one: https://em3ev.com/shop/half-twist-throttle-3-speed-cruise/ - pro tip: if you run it flipped on the left side of the handlebars so that you twist the throttle UP instead of DOWN, you can comfortably hold onto the handlebars like normal while using, you have clearance on your bar for your right trigger shifters, and theres less risk of accidental throttle engagement.

Personally I'd spend the $30 more for the cassette version of the MAC to make the install easier (just throw on your existing 9 speed cassette with a spacer and you're done)

As for someone saying 700c wheels/tires won't survive, I disagree. The Alex DM24 is very beefy. Your bike is designed to run much wider 700c tires than normal road bikes (up to 700x50 should work) so you can go with the full size Schwalbe Big Ben...it's super cushy, great grip in the rain and pavement, low rolling resistance, surprisingly decent off-road grip, good puncture protection. I have the Little Big Bens on mine (700x40 is all I can fit) and they're very comfortable even without a front shock, while the full size Big Bens are on my GFs bike (27.5x2.00) and at 37psi it feels like a full suspension bike, it's soooooo smooth. The other advantage of those are they are ECE-R75 rated tires.

Your bike is pretty light, so you'll be ok pedaling under no power on flats and declines...expect about 20mph with no motor on flats if you're in decent shape. You can use little throttle bursts to keep a constant speed here and there and get much better range. Dan is right about a larger pack if you can't charge on site though, hill climbs on your own (if your battery is dead, which is bad for it btw!) with a 40lb bike is MUCH harder than with a 25lb one. That said, I'd just remove your battery pack and take it with you to classes in your backpack with a smaller fanless 2A charger...keep the charger in the backpack with it and just sit near a wall socket.

Hope this helps, and good luck!
 
About 4 weeks ago my throttle broke and stuck in the on position. It kept me going about 12mph with the throttle in stop position. I pulled my e-brake and it cut the motor. I used it to allow power to my motor when I wanted to go as I limped home.

Nice to have it when needed.

Also, poorly adjusted, loose break cables will cause problems with e-brakes.

:D
 
e-beach said:
About 4 weeks ago my throttle broke and stuck in the on position. It kept me going about 12mph with the throttle in stop position. I pulled my e-brake and it cut the motor. I used it to allow power to my motor when I wanted to go as I limped home.

Nice to have it when needed.

Also, poorly adjusted, loose break cables will cause problems with e-brakes.

I'd agree that would be a harrowing situation...I have an on/off button so I'm covered if it ever happens. What happened with the brakes handles on mine was a short at the base of the levers where the kill wires are connected. Left/Right handlebar movement over time caused a partial break in one wire...I was amazed when I pulled back the plastic sheathing that the wire was only 20 gauge! Horrible design imho.

There's always the brake cable sensor instead you could use if you absolutely have to have it for a few extra bucks: https://em3ev.com/shop/hwbs-ebrake-sensor/ but those wuxing levers are nasty...lots of vertical play in the lever, lever pull isn't adjustable, and really REALLY tiny wires.
 
e-beach said:
About 4 weeks ago my throttle broke and stuck in the on position. It kept me going about 12mph with the throttle in stop position. I pulled my e-brake and it cut the motor. I used it to allow power to my motor when I wanted to go as I limped home.

Nice to have it when needed.

Also, they are pretty cheap. So buy a spare or spare set. No big deal if one breaks.

As for the battery, I suggest erring on the side of larger. My battery is a collection of 36v 4.4 ah packs. I bought ten of them. I did my calculations and did my first commute with five packs. My thinking was that it would be nice to have two packs of five.

My calcs were good and sure enough I was able to round trip with five. Then one day I ran a bit short on the way home. That was a bummer. What had happened is that as I became more familiar and comfortable with my bike, my route and the commute in general, I started to ride a bit faster and was using more juice. So now I run with seven packs which is about 40% more than I really need. Some days I just don't feel like pedaling as hard or I find myself in a bit more of a rush, or I've got a strong headwind, or I want to run an errand at lunch. The buffer is nice to have and the batteries aren't stressed as much. When I finally get around to making a better enclosure, I plan on using 8 packs. I'll probably add another pack of 4 for long distance trips. That should get me close to a 100 mile range if I stay around 20 mph.
 
wturber said:
Some days I just don't feel like pedaling as hard or I find myself in a bit more of a rush, or I've got a strong headwind, or I want to run an errand at lunch.

An excellent point! A headwind can DRASTICALLY change your power consumption, especially as you start getting close to 20mph...also it's easy to leave later than normal when you get used to just how rapidly you arrive places, causing you to go full throttle more often. Then there's the outside temperature.

There is a good visual range calculator that will give you an idea: http://www.electricbikesimulator.com/ make sure you change your tire size, and input the intended battery specs, as well as amp draw and motor efficiency rating...then take whatever range it gives you and multiply it by 0.75 to get more of a real-world number. Also try to figure out what percentage grade your long gradual hills are if you can...even a 2 percent grade makes a pretty huge impact on range.

More is generally better, but I learned the hard way that higher capacity at the expense of discharge rate is not worth it...voltage sag sucks! Ended up buying a higher powered lower AH 52v pack after a year (13.6 vs 11.5) and am much happier with my day to day experience. If you can afford it, get something that can handle at least 25-30A draw continuous...this one would probably work great for you: https://www.aliexpress.com/store/product/US-EU-AU-No-Tax-High-Capacity-Down-Tube-E-Bike-Battery-48V-17-5Ah-Lithium/1178407_32835239154.html?spm=2114.12010612.0.0.759c30837wJxCj
 
Yes, you generally want to make sure your battery can supply as much current as your controller can draw.

I like the Grin simulator. http://www.ebikes.ca/tools/simulator.html

But you can also shortcut using any simulator with some simple rules of thumb like assuming 25 wh/mi. You can use less than that for sure, but that's a safe number to use for most riders in most situations.
 
wturber said:
Yes, you generally want to make sure your battery can supply as much current as your controller can draw.....

I would go so far to say that you should have a battery that can supply more current then a controller can draw. If your controller draws more amps then the battery can supply you will heat up your cells degrading them at best or setting them on fire at worst.

:D
 
e-beach said:
wturber said:
Yes, you generally want to make sure your battery can supply as much current as your controller can draw.....

I would go so far to say that you should have a battery that can supply more current then a controller can draw. If your controller draws more amps then the battery can supply you will heat up your cells degrading them at best or setting them on fire at worst.

:D

I say generally, because many controllers can be configured to limit current draw from the controller. For instance, I have mine set to 80% because otherwise it will draw more than the 1150 or so watts that my boost converter can supply. But yeah, its generally a bad thing to strain your batteries with high current draw that they weren't designed for.
 
That's what I learned the first time around too...figured that a NCRB pack SHOULD be able to handle about 15A continuous, so capping my controller at 20A peak would work just fine. Well it did technically, except that after 10min it feels like a person that's crashed after a coffee spike...I've since retired it to speed position 2 duty only so it never goes past 350w and stays more consistent. The PF pack is much torquier now.
 
wturber said:
I say generally, because many controllers can be configured to limit current draw from the controller. For instance, I have mine set to 80% because otherwise it will draw more than the 1150 or so watts that my boost converter can supply. But yeah, its generally a bad thing to strain your batteries with high current draw that they weren't designed for.

Ok, but IMO I think we need to be specific for new posters (nubees) who may or may not know that frying their batteries can lead to a house fire.

:D
 
Y'all are great. A bigger battery sounds like a good idea. I'm looking at this from em3ev:
https://em3ev.com/shop/50v-14s6p-small-triangle-pack/
50V 18.6 AH with 33G cells for $429. That seems like a good price for 18.6 AH of 33G cells, right? I can charge at school pretty easily as well.

I also heard the advice about getting a separate bike. Still not sure - I'm a minimalist at heart, and will be using the ebike a lot more, I feel like I want to stick with the frame I have because I just know I like it so much.

I might just get a simple wattmeter for now, the CA feels like overkill for what I am needing.

The last things I am trying to work out is what kind of throttle to get - twist or thumb, and whether cruise control is worth it.

Also, I intend on replacing the freewheel/cassette to get higher gearing - the motor gives me the option of cassette or freewheel, is it worth the upgrade to cassette for $30? I'm trying to research to understand the differences, but I'm just not getting it...
 
sryland said:
The last things I am trying to work out is what kind of throttle to get - twist or thumb, and whether cruise control is worth it.

On my LCD/controller, I found cruise control to be cumbersome. I use PAS and a twist throttle. I adjust PAS mode between 1 and 4 depending on terrain, how fast I plan on riding, and how much I want to conserve battery. So I'll be on PAS 1 or 2 on downward inclines. On 2 for flats, and on 3 or even 4 on uphill sections. Switching PAS modes is easy on my LCD display. I then augment as needed with the throttle. But these things are significantly a matter of personal preference.
 
I would go with a good geared hub motor and the largest capacity battery you can afford. Use your current bike and buy a good solid hub motor kit from a reputable dealer that offers a warranty on their products. You will quickly fall in love with your bike all over again and look for excuses to ride it. Enjoy!
 
e-beach said:
However 700c wheels won't last long under the weight of you and the motor and batteries. The rims might take it, but the tires will wear out fast. Some around here love their fat tires, 2.5 inch or so, but in the city I prefer 1.5 inch tires.
[...]
I perfer bigger tires then 700c

Um, 700c includes 29" and 29+. So that's tires from about 18mm to 76mm in width. Your preferred 1.5" tires would be 700x38, which is a very common size for hybrids.
 
sryland said:
The last things I am trying to work out is what kind of throttle to get - twist or thumb, and whether cruise control is worth it.

I started with thumb and PAS...with a mix of non-stop distance travel (out of burbs, route along highway) then block by block stop and go downtown. I found my thumb would get sore, and PAS was annoyingly unresponsive from initial pedal stroke to engagement. The half twist 3 speed with green cruise button was 1000% better for my use...PAS when climbing or top speed.
 
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