Bicycle Conversion Recommendations

Conversion Recommendations
Bicycle to Convert: SOMA ES (Steel Frame) 30 speed Shimano 105 drop bars Commuting bike with Cane Creek Brake interrupters.
My age: 58
My weight: 200 lbs.
My (new) ride to work: 18 miles with some hills
I used to ride 12 miles each way (10 years), 4 days a week.
My experience: Experienced bicycle commuter, ride 3000+ miles annually

Desired max speed on level ground: 25 mph
Desired max range: 60 miles at 20+mph
Preferred bike wheel size: 700c (I already own the bike)
Brake type: Shimano 105 integrated shift/brake
Rider weight: 200 lb
Rider Age: 58
Rider Experience: Experienced (non ebike) 30+ years commuting
Terrain: Some hills (near end of ride)
Budget: under $1,000
Would like the least amount of drag when motor is disengaged.
Also thinking I might need 2 chargers, one for home and one for office.
I'd like to keep the drop bars and the integrated brake/shifters.

Once you get over thinking you are going to go over 60 miles, at speeds of over 20 mph, you can then plan your conversion better.
( 60 miles at 20 or 25 mph would take a very large and heavy battery, )

For Example :
I road 25 miles yesterday on the MTB conversion with street/touring tires , and I used up 80% or my battery capacity ( it has 11.6 amp hours ) Used 334 watt hours , and that was at a low speed average speed of 12 Mph .
Even if you could get up to 20% more efficiency on a Road Bike with strong legs as well, it still would not get you 60 miles.

Here is a great thread for people looking to convert a road bike. No pictures of my Road Bike, it is still a work in progress, but there are some posts
from me and others as to what you can expect from light weight road bike conversions using small light weight motors .

https://endless-sphere.com/forums/viewtopic.php?f=3&t=49691

BBSHD 24Ah battery.

No BBSHD on a Road bike, that motor is 12 lbs or even more. On a Road Bike you want a small motor like the Q100c CST. or a Q128 c at the heaviest.
The Q100c is 2.1 kg and the Q128c is 3 kg .

You are probably thinking of the other thread where someone is wondering to convert a road bike or comfort bike.

On a Comfort bike , a BBS02 or BBSHD perhaps, but Not on a light weight road bike. He would need even more ( larger and heavier ) battery pack than what he is already facing.

And he would be very unhappy with such heavy weight on his bike, remember he has said he is riding road bikes for many years .

jhotchkissca said:

My (new) ride to work: 18 miles with some hills
Desired max range: 60 miles at 20+mph

Click to expand...

Some probably worst-case analysis:

Depending on how much pedalling input you're doing at those speeds (probably not as much as you think you will) you're probably going to have an average wh/mile that's somewhere around 20-30Wh/mile, based on my experience with riding a "normal" ebike in traffic on the flats, and applying the hills on top of that. That's assuming you're intending to have an *average* speed of 20MPH+.

So 60 * 30 is 1800, meaning a 1.8KWh sized battery pack.

For a 14s "52v" pack, to make 1800Wh it'd take about 35Ah. (assuming 52v average voltage; if the average is higher then the pack would be smaller). That's a huge pack for a normal bike.

I have a 14s2P 40Ah pack on my SB Cruiser trike, made of EIG NMC 20Ah pouch cells, and it weighs about 35lbs without any casing around it to protect it, and is not small. It takes up more than a quarter of the usable space inside my seatbox on the SB Cruiser (which is not a small trike):


The pic below shows two of the 14s2p packs stacked up in the right side of the seatbox, filling that whole side. Normally I only carry one pack unless I need the extra range.




Now, keep in mind that the above is a worst-case kind of analysis, and you might not need even half that capacity to do 60miles at 20MPH+ . It depends on your actual power usage, which itself depends on the specific terrain, the number of stops and starts, how quickly you accelerate from those, how much power you actually provide via pedaling, efficiency of the motor/controller system in the specific usage scenario you have, etc.

My 14s1P 20Ah pack in a steel ammocan case is a bit mroe than half that weight and size, nearly 20lbs, and is still a lot larger and heavier than I'd want to mount on a rear rack or in a triangle; I'd be putting it in a side pannier on a normal bike (probably half on each side).

Ok,, for one thing,, lets just think about the commute for now.

What you need is a 20 ah battery, preferably 48v, for a bit more speed. Toward the end of the ride, a battery loses voltage and you slow down. So a 48v battery will give out 20 mph even a the very end.

Id go with a rear hub motor, for its reliability, vs a mid drive. Mid drive though, if you have grades above 10% to climb.

So a hub motor kit, 1000w, and 20 ah is what you are looking for. BTW,, I did a 15 mile one way commute for years, so I have a good feel what you need. Others will say you need less AH,, and nearly all days you will. But there will be days you need the 20.

Two chargers, one at work, one at home. You will need to charge at least some before you head home.


Now, for the 60 miles. You can get 60 miles from a 900wh battery (48v 20 ah). But not likely at 20 mph average speed. To get to 15 watt hours per mile on a normal bike requires heroic pedaling, or slowing down much more than 20 mph. But if you can slow to 15 mph, or even 18 mph, on your longer rides, you can definitely get 40 miles from a 900wh pack. that's a much more realistic 22 wh/mi.

Bear in mind, on that 60 mile ride, you can stop halfway for a coffee, or whatever, and snag a few more wh while you take a 30 min break. Get a 250w (5 amps) charger, and you can add 5 miles range in 30 min. Visit a friend 30 miles a way, no problem, just charge for 2 hours while on the visit.

Add a cycleanalsyst to your wish list, because knowing your real world capacity, and how much of it you used, is crucial for the longer distance rides. The CA will give you a running wh/mi average right on the display, so you can ride slower the first part of the ride, and as you reach halfway, know exactly how much faster you can finish it off.

Get your battery in a triangle shape. Its the only way you can fit a 48v 20 ah inside the frame of your bike. If you were willing to switch to a cargo bike though, then you could carry a crapton of batteries on the deck, or in the panniers. This is the way to go in my opinion. But for now, just be sure you can fit your battery in the frame of your commuter bike.

Put panniers on the bike, so you can carry a few groceries in one bag, and the extra clothes in the other. With a motor, you will need more coat in the morning in spring and fall than you think, then not need it in the afternoon. You'll be working less hard, and going much faster than you used to, and it will be chilly on mornings when its below 50f.

Being my first post, I tried to be as specific as possible. I now realize that my description was unclear because I am unclear as to what I want in an eBike.
I want a regular commuter bike with my 30 speeds and my drop bar integrated shifters. I want no drag when the motor is not engaged. But I want to be able to ask the bike to help me out and have it respond, like giving me a tailwind. I can ride 60 miles at a 15 mph average with just my legs. I am looking for a boost with the least amount of intrusion on my normal cycling feel (balance, drag, shifting, etc.)
That being said, I am concerned that once I introduce an electric motor into my commute I will use it more and more and eventually lose my hard won legs. But I guess that is between me and me.

I don't need a 60 mile range at the expense of an oversized battery. I need a 30 mile range with the motor mostly assisting my pedaling.

I bought my wife our first eBike 2 weeks ago. It is a Diamondback Overdrive ESC <https://shopsandiegoflyrides.com/products/diamondback-exc>. It was $1000 new.
I purchased it so she could go on some rides with me. I have ridden it a couple of times and really enjoy the pedal assist, but with the assist off, this bike is a boat anchor.

Right now, I am leaning toward the "Commuter Booster" friction drive, but I still really don't know what I am talking about.

Thank you all for your help and I will keep you posted on my progress.

Also, I have an ulterior motive in this research... My dream is to open up an eBike shop in San Diego and help get people out of their cars in commuter gridlock and onto bicycles. My plan is to spend a year getting to know as much as I can about the eBike world and keep my eyes open for a business opportunity. I don't expect to be an expert in a year, but hope to have gained enough knowledge to be able to be an advocate. I know bike commuting very well 30+ years, but I know next to nothing about eBikes.

With 10 Pounds of battery and 5 more of motor your bike will be a boat anchor also. Turns out that the motor won't be helping you, you will be helping the motor.

bbso2 mid drive for no drag and 10 lb. 52 volt cube battery 3 lb. since you will be mostly pedaling with 2 chargers this should work and still keep your bike like a bike. affordable at lunacycle.com. good luck in your journey and welcome to the forum.

ScooterMan101 said:

No BBSHD on a Road bike, that motor is 12 lbs or even more. On a Road Bike you want a small motor like the Q100c CST. or a Q128 c at the heaviest.
The Q100c is 2.1 kg and the Q128c is 3 kg .

You are probably thinking of the other thread where someone is wondering to convert a road bike or comfort bike.

On a Comfort bike , a BBS02 or BBSHD perhaps, but Not on a light weight road bike. He would need even more ( larger and heavier ) battery pack than what he is already facing.

And he would be very unhappy with such heavy weight on his bike, remember he has said he is riding road bikes for many years .

Click to expand...

Sorry, yes, I meant this for the other thread with two bikes and one was a Giant comfort.

THAT SAID, I saw dozens of BBSHD's put on road bikes purchased from Luna. Typically old road bikers came there to tired to keep the old pace and the speeds they wanted required even heavier motors. Those wonderful little Q motors aren't gonna give tired old roadies the speeds they want. Now I may have misread this fellow but my experience shows it's not as unusual as you may believe.

Thanks for the view!

jhotchkissca said:

Right now, I am leaning toward the "Commuter Booster" friction drive, but I still really don't know what I am talking about.

Thank you all for your help and I will keep you posted on my progress.

Click to expand...

A great first project for someone who still has legs and wants a push. Kepler is an amazing engineer. I'd read his threads and see if the shoe fits! He's also great about sharing and responding. Mid drive, BBSxx, have little drag.

BTW here's the Kepler thread. It might be a good fit. https://endless-sphere.com/forums/viewtopic.php?f=6&t=74269&hilit=carbon

Nice deal, if you got this for your wife for $1300, but you think it's a boat anchor?

You're going to be a tough customer to please.

For your requirements and the bike that you have, I agree and I would build a friction drive. Or else, I would build on another frame.

A friction drive has a good efficiency on a large diameter wheel. It is lightweight and runs on low voltage. It will make it possible to keep using all your gears without any mod, and will not make a very heavy bike to reach your target range.

The problem with these sort of threads is that everybody makes a recommendation from their own perspective without understanding OP's situation. OP has listed his requirements, but it's still not clear what he means by max speed on the flat 25 mph. Is that with pedalling or not? Does it mean a modal speed of 20 mph with occasions up to 25 mph or continuous 25 mph?

Just to throw in a different perspective. This bike maxes out at 28 mph if you pedal moderately hard, and it cruises at around 20 mph with very little effort. It rides like a bicycle and you hardly notice anything difference to a normal bicycle when you switch the power off. With comfortable pedalling, it has a range of about 50 miles from its 36v 13Ah battery. Total weight is about 20 kg.



The problem is always to find a motor that runs at the speed you want. The above one was about 270 rpm. You can make any motor run faster by increasing the voltage, but you should stick to the standards of 48v and 36v to get the best choice of components.

If you want a similar bike, any 250w 36v motor run at 48v will give plenty of power for that speed. Any 48v shark or dolphin-type downtube-mounted battery and a controller that has a proper PAS function with say 5 levels of assist through an LCD. Such a kit won't break the bank and won't spoil your bike. a 36v motor needs to be around 220 rpm and a 48v one 270 rpm. Most suppliers don't tell you the motor speed, so you need confirmation from ES members, who own them. If you want to run with something similar, say so, and then we can recommend the exact components you need.

A Bafang BBS01 or BBS02 is also a good choice. that avoids the issue of motor speed. They're very easy to install as long as your bike has a standard bottom bracket. The downsides are a very slight weight penalty compared with a geared hub motor, and the ride is not quite so relaxing because you have to do a lot more gear-changing to keep the motor in its powerband. I prefer crank motors for off-road and hub-motors for tarmac.

What build is this? Mac motor? What controller and how do you get such as clean install? You have a build thread for this?

d8veh said:

The problem with these sort of threads is that everybody makes a recommendation from their own perspective without understanding OP's situation. OP has listed his requirements, but it's still not clear what he means by max speed on the flat 25 mph. Is that with pedalling or not? Does it mean a modal speed of 20 mph with occasions up to 25 mph or continuous 25 mph?

Just to throw in a different perspective. This bike maxes out at 28 mph if you pedal moderately hard, and it cruises at around 20 mph with very little effort. It rides like a bicycle and you hardly notice anything difference to a normal bicycle when you switch the power off. With comfortable pedalling, it has a range of about 50 miles from its 36v 13Ah battery. Total weight is about 20 kg.



The problem is always to find a motor that runs at the speed you want. The above one was about 270 rpm. You can make any motor run faster by increasing the voltage, but you should stick to the standards of 48v and 36v to get the best choice of components.

If you want a similar bike, any 250w 36v motor run at 48v will give plenty of power for that speed. Any 48v shark or dolphin-type downtube-mounted battery and a controller that has a proper PAS function with say 5 levels of assist through an LCD. Such a kit won't break the bank and won't spoil your bike. a 36v motor needs to be around 220 rpm and a 48v one 270 rpm. Most suppliers don't tell you the motor speed, so you need confirmation from ES members, who own them. If you want to run with something similar, say so, and then we can recommend the exact components you need.

A Bafang BBS01 or BBS02 is also a good choice. that avoids the issue of motor speed. They're very easy to install as long as your bike has a standard bottom bracket. The downsides are a very slight weight penalty compared with a geared hub motor, and the ride is not quite so relaxing because you have to do a lot more gear-changing to keep the motor in its powerband. I prefer crank motors for off-road and hub-motors for tarmac.

Click to expand...

I love my triple chainring in the front and don't want to give it up. I use it for slow downhills and when I am angry,

The bike I am retrofitting is the first bike I have had fit and built to my size/cycling style (hand picking every component).

I am thinking I may have 2 bikes to build. A friction motor for the SOMA and a bafang mid drive motor for a bike I find on Craigslist with disk brakes.

I am hesitant to go with front or rear wheel motors, but I am not sure why. I think the front hub would compromise bicycle handling, and the rear motor would interfere with my Shimano 105 10 gear cassette.

Am I making sense? Again... I am new to this.

jhotchkissca said:

I think the front hub would compromise bicycle handling, and the rear motor would interfere with my Shimano 105 10 gear cassette.

Am I making sense? Again... I am new to this.

Click to expand...

You can get cassette motors that can use your existing gears. In order of size: Keyde 100SWXRC36, Q100C, Keyde 110SWXRC36, MXUS XF07C, Q128C, Bafabg SWX02C, Mxus XF08C. Xofo CST, Bafang CST. they're the common ones available as kits. There are loads of others from various OEM suppliers too, like Dapu and Panasonic. The motor in the bike in the above photo I posted has a Bafang CST with 9-speed cassette.

You don't need a triple chainring when you have electric assistance. A double one is enough for off-road use. On the road, all you need is a single.

Okay, I think you have talked me into the Bafang CST. Can I keep my triple? I want to be able to ride the bike with no power if my distance outrides my charge.

Retrofitting my road bike to the CST will not do any permanent damage to it, will it? I'd like to remove the motor and get the bike back to non-assist if I don't like the tradeoff.

Also, would you recommend me trying to make my own battery? I thought it might be nice to have the battery be the first layer of my trunk bag, but am concerned I may be getting in over my head.

Thanks for all the help.

JimH

All the to do about a hub front changing the bike handling is blather. I have three mid drives currently running and two front drive. I like the geared front drive best. Its a great ride but will spin out on sand or slippery wet streets. A reaDD is something ive ordered and have ridden over 100 miles its great. I usec a freinds and like it enough to buy one more motor. Dont discount a front drive for s liesure or flat street bike. They are easy to install and not a huge change in ride. I don't get those complaining.

jhotchkissca said:

I love my triple chainring in the front and don't want to give it up. I use it for slow downhills and when I am angry,

The bike I am retrofitting is the first bike I have had fit and built to my size/cycling style (hand picking every component).

I am thinking I may have 2 bikes to build. A friction motor for the SOMA and a bafang mid drive motor for a bike I find on Craigslist with disk brakes.

I am hesitant to go with front or rear wheel motors, but I am not sure why. I think the front hub would compromise bicycle handling, and the rear motor would interfere with my Shimano 105 10 gear cassette.

Am I making sense? Again... I am new to this.

Click to expand...

No triple rind with a mid. Often no problem with a read drive but chainline can change. Sometimes a gear of two are lost.

I have no horse in this race so to speak, but i think you should seriously consider the Kepler drive. Do a search here if you haven't already. It would be quite a bit more appealing to someone who just wants a boost. San Diego is relatively dry and flat. You can go with super light battery or double up for long range.

Ok, we understand better now. But unfortunately, any e bike is going to be a bit like a boat anchor, or, not much help in the first place.

Given your ability to pedal, which I always assume to be moderate until told otherwise, I think you could get a 50 mile ride, at 20 mph, from your wifes bike.

If you put out 200w, then going 20 mph will only take about 150w of electric power more. ( pedal watts don't equal motor watts one for one, the motor wastes more of the power) if her battery is 400 wh, then it should last about 2.5 hours, or 50 miles at 20 mph.

You won't lose your legs, if you keep that thing in a limited power mode, vs full power.

If you set a very very low power limit, then the motor will put out only about 50-75 watts. that is about what it will take to eliminate the boat anchor effect. To counteract the extra weight, you have to add a bit of power. Not much, but without it, it's like riding around with a case of beer in your panniers.

So look for a very light motor, perhaps a rear geared hubmotor in the 350 rated ballpark. ( still about 7 pounds though!) Look for a display that offers a wide range of assist levels, since you want a low assist.

Then you need a slightly larger battery than I think your wife has. Not a 1000wh like I first suggested. But a solid 700 or so, about 12 pounds. It will be close to 20 pounds added to your bike.

Which is where the next suggestion comes from. DONT ruin your favorite bike with the motor. Get a reasonably good bike, perhaps as light as 25 pounds, and put the motor on it. Type of bike is up to you, but I strongly suggest a nice light for steel, chromoly frame. The bike could be 25 years old, just have it be a good frame, with that wonderful whippy cromo feel. The kind of thing they make fixies out of. You can have 9 gears on that rear hub motor. That should be enough.

I have a Sram WiFly 10 speed cassette ( 11-32 ) on my little Q100c CST Rear Hub motor . The only difference between it and a 9 speed cassette is that the lock ring has about 1/4 less turn ( less to thread onto the Cassette Freehub Body ) than the 9 speed,
It is working fine , there is still enough to tighten up the 10 speed cassette to keep it tight on the Cassette Freewheel Hub Body .
I live in a hilly area, so I experience the type of hills you have in San Diego , Yesterday's ride was 600 total feet of climbing / descending . with the little Q100c CST rear hub motor/on Road Bike , with a double chainring up front 2 x 10 . ( yes I did drop down to the smaller front chainring when climbing up a couple of the steeper hills so I understand the need for at least 2 up front when living in certain areas of the country )

Many sportif/casual Road Riders have gone to a 11-32 tooth rear 10 speed cassette , now that many bikes come with 2 chainrings up front at the crank.

The only reason I am not trying Kepler's new friction drive , is because I already have 3 built up rear hub motor wheels . For your light weight bike I would really consider it over any hub , front or rear.

For the best range I would guess that Kepler's newest version / friction drive will give you the most distance per watt hour of battery capacity.

Some day I will have a mid-drive, But Not the Befang's , I am waiting for the Newer/Better/ Next Generation of Mid-Drives to hit the market. In the meantime, a Little Q100c or Q 128 c Rear will work on your 2nd craigslist bike .

jhotchkissca said:

I love my triple chainring in the front and don't want to give it up. I use it for slow downhills and when I am angry,

The bike I am retrofitting is the first bike I have had fit and built to my size/cycling style (hand picking every component).

I am thinking I may have 2 bikes to build. A friction motor for the SOMA and a bafang mid drive motor for a bike I find on Craigslist with disk brakes.

I am hesitant to go with front or rear wheel motors, but I am not sure why. I think the front hub would compromise bicycle handling, and the rear motor would interfere with my Shimano 105 10 gear cassette.

Am I making sense? Again... I am new to this.

Click to expand...

Thanks for the info. I like your solution. But I am also attracted to the friction drive and I like the elegance of a mid drive.

This is a much more nuanced topic than I anticipated. It seems like a balance between how much you want your bike to be a bike and how much assistance you want.

Right now I am 80% bike and 20% assistance. But I think that once I introduce the assistance into my commute, that number will creep.

What is the value in a solution that recaptures bicycle braking to help recharge the battery?

Sorry for all the wandering questions. I find this field fascinating.

JimH

Leave that bike alone and let it be a bike at least for now. Go to Craigslist get yourself another bike $150.00 and start playing taken apart put it back together getting it right and you'll still have your beautiful bike to ride in the meantime. When you get it right you can exchange it. Anchors Aweigh.
If you must go with the kelper or front geared motor.
You want to see a real ebikes store go see my friend Howie in Corona Del Mar 70 ebikes on the floor.