Is this bicycle, a Scott Sub 20 hybrid, a good candidate for conversion to E-bike?

Great thread. Really has me thinking about my Specialized CrossTrail …
The CrossTrail would be nice as a conversion. If it were mine I would put on a bar like this and some gravel tires. It would change the entire bike's personality. I did this bar on a mountain bike, but that required drop bar levers, so it was a bigger job: https://www.somafab.com/archives/product/condor-2-handlebar
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Pics or it didn't happen! ;-P
I dropped it from an 11-speed to 9 so it would be more robust and chains and replacement cogs are less expensive. If I were to do it with hydraulic levers it would have been very pricy so now it has mechanical brakes which are low maintenance and easy to adjust. While it still had a flat MTB bar it was a 1,000Watt Bafang for three weeks. That ate the SRAM 11-speed cog and was stupid to ride - thrilling at first but no feel. This is my go to bike for long rides because I can change up positions on the riser, short drop with the flare. It is a wonderful climber with the standard 42 chainring.
 

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I dropped it from an 11-speed to 9 so it would be more robust and chains and replacement cogs are less expensive. If I were to do it with hydraulic levers it would have been very pricy so now it has mechanical brakes which are low maintenance and easy to adjust. While it still had a flat MTB bar it was a 1,000Watt Bafang for three weeks. That ate the SRAM 11-speed cog and was stupid to ride - thrilling at first but no feel. This is my go to bike for long rides because I can change up positions on the riser, short drop with the flare. It is a wonderful climber with the standard 42 chainring.
I have to admit, while I'm just not a drop bar guy in real life, I certainly love the look of a nice subtle set like that.
 
The small display will be fine. It just cannot fit on the inside of a bend. So put it on top of the bar to the left. You are not going to be looking at the display, just like you don't squint at a shifter. You will be using it by feel.THe reason I was concerned about the display is that on the website The XH-18 Display - Left Handlebar Mount Half Twist Action:The XH-18 Display Mounts on the left side of your handlebar, featuring a spring loaded half twist mechanism to cycle between the 4 levels of assist.

The display in your photos does not appear to be the XH-18 which has a twist mechanism. That is why I was concerned about mounting position. What model is the display in your photos?

 
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The display in your photos does not appear to be the XH-18 which has a twist mechanism. That is why I was concerned about mounting position. What model is the display in your photos?

That is the VLCD6 display. It is very simple and the readout is only in Km. But I don't use a wheel magnet or the speed pick up so that does not matter to me. With this display, hold the power and plus to toggle between 45K and 25K limits. Hold plus and minus to get to the set wheel circumference menu. For settings I go with a 45Kph limit on 100cm circumference wheel, that is telling the system it has 13.6 inch wheels, so it better try to keep up to go 45. That is the setting on my 29'er. So I have 231cm around wheels that think they are 100cm around.
 
That is the VLCD6 display. It is very simple and the readout is only in Km. But I don't use a wheel magnet or the speed pick up so that does not matter to me. With this display, hold the power and plus to toggle between 45K and 25K limits. Hold plus and minus to get to the set wheel circumference menu. For settings I go with a 45Kph limit on 100cm circumference wheel, that is telling the system it has 13.6 inch wheels, so it better try to keep up to go 45. That is the setting on my 29'er. So I have 231cm around wheels that think they are 100cm around.
Thanks, looks like that display does not come as part of a kit and has to be ordered separately.
 
I have had to order them separately for a couple of weeks. That will clear up by the end of October. You can install this display without moving the brake lever and grip. It slips down over the bar. Since it is a Winter project, just wait three weeks before ordering. Or ask your vendor to not send a display and credit you $20. Then order and install the small display later. Hang your display wire with a weight for 48 hours to get out the shipping kinks. A heat gun helps.
 
PedalUma
1) You appear to favor using the 36V 350W unit. Am I to understand that this model will probably be best for my intended use and be the most efficient? I'm looking for a setup that will get me through 40 mile rides while pedaling at a reasonable pace. I'm not looking for speed just want it to feel like I always have a tailwind.

2) Will a 36V 350W unit with a 36V 10AH battery more than likely meet my requirements?

3) Why not just go with the 36V 500W motor? Same price, same weight, more power if I need it. Is the 350W more efficient and that is why you recommend it? You stated that 48V batteries tend to be heavier so I understand avoiding 48V units if you are trying to keep the weight down and don't need the extra power.

4) I'm also kind of confused as it appears the motors 250W-750W are all basically the same size, weight and price. How do they differ? Is it just firmware settings by the manufacturer.

Sorry, if you have already actually answered some of these questions. I may end up doing this project sooner rather than later.
 
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Gionnirocket, thanks for your help with this. I'm really looking forward to this conversion. I like the fact that the conversion can be done without changing the "look and feel" of the bike very much. Is there a reason you chose the Bafang over the Tongsheng mid drive? Is there a recommended supplier for these motors?
I went with the Bafang as I wanted, or should I say thought I needed 750w. I do live in a hilly area but still power the bike mostly myself. I've tamed the BBS02B down quite a bit but I do occasionally like the feel of the power available. Most of the time I'm riding for exercise, but I do enjoy powering up a steep trail and the BBS02B does it easily. Honestly I didn't research the Tongsheng much as it seemed at the time the Bafang was more popular, especially for a mtb. It would be interesting to ride one now for comparison. I know this isn't much help... but that's all I got 🙃
 
Does a battery like this connect without any issues to the TSDZ2? I'm thinking the 36V 10.5ah Samsung would be the one to go with. Wonder if I can get away using something smaller that will hold up on a 40 mile ride, on flat terrain with me doing most of the work?

 
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Couple things
- If your donor bike has cables that run under the bottom bracket you might have to re-route those cables or trim the cable guides down if they obstruct the motor case. See the other recent DIY TSDZ2 post where this is an issue for him.
- If you choose the xh18 display you will not be able to run the motor without the speed sensor with spoke magnet - I tried that and found that the system would automatically shut down every several minutes even while pedaling in an assist level. The shut down is very bothersome because you have to power the system up again and wait several seconds to allow the torque sensor to calibrate before pedaling again. Also the xh18 will shut down automatically even with the speed sensor unless you are using an assist level other than 0. So for that bike I always ride in at least assist level 1 (which uses very little current unless pedaling slowly with resistance like up a hill) and with the speed sensor attached.
- In order to get the extra boost with the 350w version that Pedaluma refers to by not using the speed sensor you lose the speedometer/odometer function. I like having those functions, especially the odometer function. So if you want to have the speedometer/odometer function you might want to choose the 500w version (or 48v 750w version if you want even more power).
- there is a 4th display that I don't see listed but is available from eco-ebike. C3 display which is a nice option that can be programmed to display mph instead of kph and has 5 levels of assist instead of 4. The 5th level is useful if you choose a 48v 750w version because it isolates the highest level of assist without losing the other 4 levels. I rarely ride in level 5 because it seems excessive for most of my use - but it is nice to have available if needed. I don't see that the 5th level would be helpful for the 36v 500w version that I run the xh18 display on.
- Eco-ebike is good about answering questions, they might have display option packages that they don't list (like the C3 display that I got with my 48v version) just ask them.

small handlebar mounted C3 display
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Thanks EMGX. I am aware of the cable guides issue and am prepared to deal with that. I will go with the 36V 500W motor and the small VLCD6 display that PedalUma suggested. I am not able to find a 36V 350W kit with the VLCD6 display, that is why I'm going with 500W. I want to keep my built as simple as possible like PedalUma also suggested. If that means I don't have a speedometer or odometer that is fine. The fewer cables or sensors that I have to mount the better.

I am considering wiring a headlight and taillight to the bike if that can be done relatively easily. I'm hoping there are some good quality headlight available.
 
I put a bottle topper on a similar battery with gasket sealant. The 36/10.5, 500W will be nice. You will be better off not using the 6V light kit. It is not very bright and adds tangles of messy wires. IMO better off with USB rechargeable lights. You can charge these if needed from the battery's USB port. They are bright, clean looking and inexpensive. I have done one lap of Sonoma Mountain with a 36V/10.5Ah. That was 39 miles with 1,800 feet of cumulative climbs. We stopped at Jack London State Park above the Valley of the Moon for lunch. And we faced N. headwinds from the SF Bay, then from the sea to the West through the Petaluma Gap. Those were 20Mph winds. These winds are caused by the 35-degree difference in temp between the Coast and Inland.
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A guy just brought in a Lynskey Titanium MTB with a Deore XT build.
 

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Thanks PedalUma, I'll look into those USB lights. Trying to keep the bike looking clean. That's some high end frame, are you going to install a TSDZ2 in it?
 
Yes. He test rode the blue Specialized MTB with the drop bar and wants the 350W conversion. He test rode expensive bikes at stores but likes his bike and like you, he wants to keep its character. The conversion is a birthday present from his wife. Then she will want a Boda Boda conversion for her birthday. I let her sit on one today. She is giddy. I need to get back to today's 1983 conversion project. I think the new 'dork disk' is a nice touch. A dork disc is the plastic thing that turns yellow between the cassette of gears and the rear spokes. Miami Vice, LA Olympics '84 teal. It took four colors of nail polish to match for touch up. The 6'6" owner can now paint his toes to match his bike.
 

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A dork disk is required on a bike of that vintage. Funny my other bike is a Miyata Nine 14 that I purchased new sometime in the 80's. Fortunately it is in black but it still has its dork disk. It's still in great shape as I mostly rode my other bikes. I'll use the Nine 14 if I want to ride unassisted. Great bikes.
 
Received my TSDZ2 unit. I would like to remove the chainguard but if I do that I cannot tighten the chainring using the supplied bolts. Do I need to obtain different chainring bolts?
 
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