Want to build a low drag commuter

Deno

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Jan 24, 2018
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I currently commute on a Cube eMTB with a Bosch CX motor and to be fair it has done a massive shift, clocking over 20k km. I've had the motor rebuilt but the battery is starting to loose capacity and I reckon this might be its last winter.

I want to spec a new fast, efficient commuter bike and have been thinking about my requirements:
- I like torque sensing over cadence. I am pretty fit and like getting a bit of daily exercise and in that way my current setup suits. Interested in Woosh's XF07 TS kit.
- Open to a rear hub motor as I am not convinced with TSDZ2 reliability at my usage level and I suppose I could do without changing the drive train every 3k or so.
- 32km there and back commute so reasonable capacity
- needs to cruise at 40km/h+ like my current bike does.
- Hydraulic brakes
- Drop handlebars
I have been looking at Gravel bikes like the Genesis CDA series due to large tyre clearance and mounting points for racks and mudguards etc. but they only come with mechanical disks which are poor by all accounts. Aftermarket fitting of hydraulic brakes is expensive due to roadbike brake levers so that not an option. Any of the gravel bikes with hydraulic brakes seem to have thru-axles which scuppers my plan for hub drives.

Does anybody know of a suitable gravel/touring type bike with hydraulic brakes and QR axles that would be conversion friendly?
What TS hub drive / battery combo would people recommend?
Am I overthinking this?

Thanks.
 

matthewslack

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Nov 26, 2021
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I currently commute on a Cube eMTB with a Bosch CX motor and to be fair it has done a massive shift, clocking over 20k km. I've had the motor rebuilt but the battery is starting to loose capacity and I reckon this might be its last winter.

I want to spec a new fast, efficient commuter bike and have been thinking about my requirements:
- I like torque sensing over cadence. I am pretty fit and like getting a bit of daily exercise and in that way my current setup suits. Interested in Woosh's XF07 TS kit.
- Open to a rear hub motor as I am not convinced with TSDZ2 reliability at my usage level and I suppose I could do without changing the drive train every 3k or so.
- 32km there and back commute so reasonable capacity
- needs to cruise at 40km/h+ like my current bike does.
- Hydraulic brakes
- Drop handlebars
I have been looking at Gravel bikes like the Genesis CDA series due to large tyre clearance and mounting points for racks and mudguards etc. but they only come with mechanical disks which are poor by all accounts. Aftermarket fitting of hydraulic brakes is expensive due to roadbike brake levers so that not an option. Any of the gravel bikes with hydraulic brakes seem to have thru-axles which scuppers my plan for hub drives.

Does anybody know of a suitable gravel/touring type bike with hydraulic brakes and QR axles that would be conversion friendly?
What TS hub drive / battery combo would people recommend?
Am I overthinking this?

Thanks.
Most hub motor setups do not have torque sensors. They are available, but relatively costly which does not always sit well with the low cost of a hub motor!

You might find a visit to endless sphere useful research, and for comprehensive component availability and expertise, Grin Technologies at ebikes.ca.
 

soundwave

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May 23, 2015
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soundwave

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he is running the controller to the limit going that fast, it will also nuke the batt range wise.
 

guerney

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he is running the controller to the limit going that fast, it will also nuke the batt range wise.
He only needs 2 miles range to whizz past those cyclists at 65-ish mph - after a mile to slowly get up to speed on low gearing and controller load, to OTT 80T. I feel let down, disappointed. :(
 

soundwave

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guerney

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he is running the controller to the limit going that fast, it will also nuke the batt range wise.

You call that a chainwheel? THIS is a chainwheel!


 

soundwave

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May 23, 2015
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i have a 21t on the front of my bike but as it uses the bosch small chain ring it is reduced buy 2.5 so if i had a normal size chain ring it would be 53t.

i did try 25t but the motor was to Overgaard and just made the bike worse in every way.

DSC_0673_01_01.JPG

now if i go over 21t to 22 i cant hit 120rpm to get max power from the motor and with 18t i reach spin out so 21t is best for my way of riding.
 
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guerney

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i have a 21t on the front of my bike but as it uses the bosch small chain ring it is reduced buy 2.5 so if i had a normal size chain ring it would be 53t.

i did try 25t but the motor was to Overgaard and just made the bike worse in every way.

View attachment 45539

now if i go over 21t to 22 i cant hit 120rpm to get max power from the motor and with 18t i reach spin out so 21t is best for my way of riding.
Very nice! I've got 52T on mine - the Bafang BBS01b copes fine (even on hills), and if I was foolishly young again I'd probably opt for a 60T or more, because I'm sure there's enough torque for suicidal speeds even with my legal 15A 250W 36V kit... which leads me to believe that the Bafang HD is capable of much higher speeds than in that video.
 

soundwave

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m8 has a 750w bafang and can nuke me on a standing start as double the torque to my 60nm but can keep pace after that just lol.

tho he uses a throttle and after a year zooming round his 52v batt is showing it range wise so thats the price you pay.
 

guerney

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m8 has a 750w bafang and can nuke me on a standing start as double the torque to my 60nm but can keep pace after that just lol.

tho he uses a throttle and after a year zooming round his 52v batt is showing it range wise so thats the price you pay.
The only reason you can catch up is because his chainring is too small, tell him he needs a 80T! Actually, he'll die, don't tell him... :oops:
 

guerney

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m8 has a 750w bafang and can nuke me on a standing start as double the torque to my 60nm but can keep pace after that just lol.

tho he uses a throttle and after a year zooming round his 52v batt is showing it range wise so thats the price you pay.
How's your mate with the crushed bike and ribs? Did he ever get his bike back from the cops?
 

soundwave

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he got it back months ago and no charges
 

guerney

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he got it back months ago and no charges
Wow! That's a good result! I'm amazed. Still, very nasty accident...is the bike repaired or did he buy a new one?
 

soundwave

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the bike frame was junk in the first place prob why he got it back lol
 
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Deno

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Jan 24, 2018
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Most hub motor setups do not have torque sensors. They are available, but relatively costly which does not always sit well with the low cost of a hub motor!

You might find a visit to endless sphere useful research, and for comprehensive component availability and expertise, Grin Technologies at ebikes.ca.
I was looking at the whoosh kit that mates to an xf08 rear hub. Doesn’t seem too expensive.
 

soundwave

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well if you want 40kph+ that motor is not going to cut it and a bafang mid drive would be a better option as you can set up the controller via software and tune the motors for your usage.


why not get a new batt for the bosch ? there are 3rd party 750w frame batts but there 1k

 
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Deno

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Jan 24, 2018
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What’s the lifespan of a tdsz2 or a bbs mid drive though? I read on here that the need frequent strip downs etc. I’d rather stick with 18k km troublefree from my Bosch.

I suppose I’m asking is there a hub drive kit that can take a TS and still do 40k+.

I could just buy a new battery alright but the rest of the bike is worn. It will need new wheels / gear cables / tyres soon. Headset needs attention too. It’s getting a bit like triggers broom. And when all that’s done it will probably still need charging at each end of my 16k commute as it’s a big heavy mtb that pushes a lot of air at 40kph.