Fat Bike build 500W TSDZ2 Middle Motor

[MaartenL]

UPDATE 2018-08-19

Still going strong! Actually nothing broke really, it was the chain making problems. It was a little loose and would jump off, so I made it a little tighter.

420km on the road!

UPDATE 2018-07-30

First time builder from The Netherlands / Europe
190 cm /6.23 foot
80kg / 176 lbs
Terrain is all-in FUN from road to the beach to off-road steep climbing

So I bought a Dutch Fat Bike from Switzz Bikes!

Fat 8.1 specs:
Wheels 26"
Tires: Kenda Juggernaut Sport 26″x4.00
Frame: Aluminium 6061
Disc Brakes: Tektro Aquila Mechanical Disc
Gears: 8 Speed Shimano Clarius
Chain: KMC -72
Cassette: 8 Speed HG41

Dropout / HUB spacing / Axel for rear wheel: 197mm and Switzz says I need 220mm!
Bracket for midmotor: 120mm

So I bought the Fatbike kit from www.future-bike.it

500 W option with 120mm bracket
Protection cage for motor
48V 17Ah battery in bottle form which can be removed
Race Control Display type VLCD6
Metal Gearings as standard
Speed sensor
42T with 10mm offset (installed this one)
42T standard
32T race torque thing I will never use...

Maxspeed is around 40km/h, than I pedal so fast the motor stops assisting...
I can really climb hard with this bike! So far one big LOVE for this built!
I did a test ride on a 18km technical, steep short climbing MTB track in The Netherlands and it was awesome!

Installation took some time to figure it all out and some issues:
-Battery could only be mounted upside down on two M5 bolts (so far no problems, but double check to lock the battery before riding)
-Speedsensor did not work but found some strong neodymium magnets which fixed the distance problem
-Motor would rest on a part sticking out from the motor on the left so I bought a wedge to fit in the middle
-The bolt which should fit on top did not fit because of the big diameter of my frame. I just did not use it....

Pictures!

Thanks for all support!

The only issue is still that I'm wondering if the motor doesn't lean too much on the edge of the frame / is able to move because I could not install the top bolt because of the big frame.

 

[81forest]

Sounds like a cool project. Definitely read up on the firmware problems with the latest BBSHD, as far as I know it has not been fixed. Basically the throttle and PAS don’t get along and people are disabling the PAS right out of the box to make it rideable. Not what I want to do with a brand new kit.

There are some other cool (maybe better) mid drives right now. I was all set to buy the BBSHD, but now I’m liking the lingbei.

You’ve only been reading for a couple days?! I think you have to binge on this site for at least 80 hours before you can make up your mind (speaking from experience)!! :lol:

 

[MaartenL]

Thanks for the feedback!

After reading a lot about the problems of the BBSHD and a middle motor in general on a cheap bike I changed my mind towards a rear HUB motor instead.

As of now this would be my setup from em3ev on the BTwin MTB Rockrider 520 cheap bike.
27.5" which is the only downer, so I hope I can use 26" wheels instead for the bike.
It does have Disc Brakes, so maybe it's easy to change.

• Mac Motor & Axle Type - Standard Rear, Freewheel, 135mm
  Mac Motor Wind - 8T 50KPH (30 MPH) at 48V/26" Rim
  Controller Type - 6 fet 3077 (36-52V, 25A)
  52V 25.7Ah High-Energy Pack With 60A Smart BMS
  58.8V 5A Charger (with 90/100% Switch)

• CA3-DPS, Cycle Analyst Ebike Computer
  Cycle Analyst Mounting Bracket (Steerer Tube)
  CA3 Cycle Analyst PAS Speed Sensor

• Half Twist Throttle With 3 Speed And Cruise
  Ebrake Type - Mechanical Ebrakes Lever (pair)

• Rim Type: 26" Alex DM24 Disc
  Spoke Type: 13G Sapim Black
  Torque Arm - Rear Rev4
  Freewheel Type - 7sp DNP (11T)
  DNP Extractor Tool --> what for? do I need this?

 

[leo99]

Hi,
I think the hub option is much better suited to your situation. just go with the motor with cassette, it's much better. freewheel have a tendency to break. they finally have a cassette option, I think it would be a mistake to not take it. The dx32 rims are supposed to be bombproof so it might be a better choice.

The bike does not have any disc brakes and it does not look like you can put any. I would really recommend disc brakes at those regular speeds.

good luck with you build
Léo

 

[MaartenL]

Thanks for the feedback. I changed bike & rim type so it becomes:

BTwin MTB Rockrider 520 cheap bike.
https://www.decathlon.nl/p/mtb-rockrider-520-27-5/_/R-p-120236

27.5" which is the only downer, so I hope I can use 26" wheels instead for the bike.
It does have Disc Brakes, so maybe it's easy to change. I hope these brakes are any good, the reviews are good!

• Mac Motor & Axle Type - Standard Rear, Cassette, 135mm
  Mac Motor Wind - 8T 50KPH (30 MPH) at 48V/26" Rim
  Controller Type - 6 fet 3077 (36-52V, 25A)
  52V 25.7Ah High-Energy Pack With 60A Smart BMS
  58.8V 5A Charger (with 90/100% Switch)

• CA3-DPS, Cycle Analyst Ebike Computer
  Cycle Analyst Mounting Bracket (Steerer Tube)
  CA3 Cycle Analyst PAS Speed Sensor

• Half Twist Throttle With 3 Speed And Cruise
  Ebrake Type - Mechanical Ebrakes Lever (pair)

• Rim Type: 26" Alex DX32 Disc
  Spoke Type: 13G Sapim Black
  Torque Arm - Rear Rev4
  Freewheel Type - 7sp DNP (11T)
  DNP Extractor Tool --> what for? do I need this?

 

[leo99]

You do not need the freewheel type 7sp and dpn extractor tool since you use a cassette that you can buy at decathlon. It's very easy to put a 26 inch wheel at the place of the 27.5 but then the front of the bike will be higher and you will have slightly less clearance with your pedals just so you know. I wouldn't place my hopes to high for the breaks you will have cheap bike will have cheap brakes and you will be going fast. They won't last long better and won't be great, maybe buy a better front brake.

Ps: dpn extractor tool is a tool to take off a freewheel

 

[footloose]

• Mac Motor & Axle Type - Standard Rear, Cassette, 135mm
  Mac Motor Wind - 8T 50KPH (30 MPH) at 48V/26" Rim
  Controller Type - 6 fet 3077 (36-52V, 25A)
  52V 25.7Ah High-Energy Pack With 60A Smart BMS
  58.8V 5A Charger (with 90/100% Switch)

• CA3-DPS, Cycle Analyst Ebike Computer
  Cycle Analyst Mounting Bracket (Steerer Tube)
  CA3 Cycle Analyst PAS Speed Sensor

• Half Twist Throttle With 3 Speed And Cruise
  Ebrake Type - Mechanical Ebrakes Lever (pair)

• Rim Type: 26" Alex DX32 Disc
  Spoke Type: 13G Sapim Black
  Torque Arm - Rear Rev4

• 
  
  The config you are looking at is a rock solid performer.
  I have a very similar setup, has done great for four years.
  And em3ev is a good choice of supplier.
  
  Couple suggestions:
  1) Don't get a new cheapo bike with front suspension. Cheapo suspension is junk, and you won't be happy with it. In the Netherlands you are so fortunate to have wonderful bike paths -- you don't need suspension.. Suggestion: get a good used 26" mountain bike w/o suspension. Put a couple reasonably wide tires on it. I use Schwalbe Big Apples, they ride great and smooth out the small bumps just fine.
  2) I used to run a 9 fet 3077 controller combined with Cycle Analyst so I could set amp draw as I wanted as well as track power use. That worked fine, but eventually the CA died. So I removed it, and replaced the 9 fet controller with a 6 fet 3077 controller. For my riding style, it was a win. Turned out 6 fet controller was fine and it drew just right power for my use without needing CA, and the setup is cleaner. You may find that CA isn't needed, except if you want to set power draw to stay within EU street-legal level.
  
  My bike:
  
  

 

[81forest]

I agree 100% with the advice above, you will not benefit at all from a cheap suspension fork. A rigid steel fork is great and absorbs a lot of bumps with a nice fat tire, and you will have way better steering feedback and better control.

 

[markz]

What absorbs bumps is a fat tire.

 

[81forest]

What absorbs bumps is a fat tire.

Steel helps too. Ever ride with a straight blade aluminum fork? Steel is real!

 

[MaartenL]

Thanks you all! Your feedback is very welcome and makes everything much easier. Now I have the feeling I know what I'm talking about.

So! This morning I was browsing a Dutch forum and found about this 2017 Rad Power Bike:
https://radpowerbikes.eu/

They are actually selling the 2017 model in Utrecht (45min drive from my home) for EURO 1399,- / USD 1638. Crazy cheap... actually cheaper than what I could build myself if I had to buy a bike myself.

However it is limited to 25km/h but I assume that is something I could improve...

I'm researching this bike now and see if it is any good... :O

 

[footloose]

IMHO Rad bikes offer pretty good value for the money. At a discount, even better.
Couple things to think about though...
1) that battery is not going to give your target range of 50km / 30m into even a mild headwind
2) 4" fatties generally best for low speed riding, not higher speeds
3) if you build your own, then YOU can fix / maintain / repair it as needed (for some a plus, for some a minus :wink: )

 

[markz]

What absorbs bumps is a fat tire.

Steel helps too. Ever ride with a straight blade aluminum fork? Steel is real!

Justin on the Europe to China Sun Tour went from high psi regular tires to Canadian Tire Kenda fat tires, he noticed a great improvement on ride quality, no more saying "Bump Ahead!" to his tandem rider. I have always kept my eyes open for a used fat fork at the community bike to use on one of my bikes but they never show up, not much rotation of stock. I will end up just buying a new $75-100 Sunlite Fat Fork and one of my busted FS bikes has a 165mm rear dropout, which will get a mxus 5000W which requires more then standard width, something like 145-150mm.

I used to do a lot of trail riding, even rode down Nakiska ('88 Olympics) ski mountain before it became popular. Nothing crazy, I have always been a fan of controlled slow-moderate riding. Went through a phase 18 yrs ago where I'd skid down steep slopes. But now I am a fan of cruising for pleasure, getting from point A to point B, easy single track through the tree's. I am too cheap to just buy a fat bike, but I can make one out of that frame I have.

I too have been pondering a long distance ebiking ride. I've ridden 75km within the city multiple times. Went to Cochrane about 30km from the train station. It had a long steep hill that I climbed well. Here is a map. 3.3km in length on the highway.
https://www.google.com/maps/@51.195807,-114.4355621,3a,60y,220.66h,77.02t/data=!3m6!1e1!3m4!1sBA9appGOc5PTYLeyA65qog!2e0!7i13312!8i6656

https://ridewithgps.com/routes/12818579

 

[81forest]

Justin on the Europe to China Sun Tour went from high psi regular tires to Canadian Tire Kenda fat tires, he noticed a great improvement on ride quality, no more saying "Bump Ahead!" to his tandem rider. I have always kept my eyes open for a used fat fork at the community bike to use on one of my bikes but they never show up, not much rotation of stock. I will end up just buying a new $75-100 Sunlite Fat Fork and one of my busted FS bikes has a 165mm rear dropout, which will get a mxus 5000W which requires more then standard width, something like 145-150mm.

I used to do a lot of trail riding, even rode down Nakiska ('88 Olympics) ski mountain before it became popular. Nothing crazy, I have always been a fan of controlled slow-moderate riding. Went through a phase 18 yrs ago where I'd skid down steep slopes. But now I am a fan of cruising for pleasure, getting from point A to point B, easy single track through the tree's. I am too cheap to just buy a fat bike, but I can make one out of that frame I have.

I too have been pondering a long distance ebiking ride. I've ridden 75km within the city multiple times. Went to Cochrane about 30km from the train station. It had a long steep hill that I climbed well. Here is a map. 3.3km in length on the highway.
https://www.google.com/maps/@51.195807,-114.4355621,3a,60y,220.66h,77.02t/data=!3m6!1e1!3m4!1sBA9appGOc5PTYLeyA65qog!2e0!7i13312!8i6656

https://ridewithgps.com/routes/12818579

I would love a fatbike in the stable as well. It’s amazing how long we all rode skinny rims and 2.1” tires, thinking those were “fat tires”!

 

[MaartenL]

You all have convinced me to come up with a plan for a fat bike:

Im open for better suggestions for a bike to convert.. I found this one:

MBM FATBIKE FAT 26"
https://spaarbikes.nl/products-page/cruisers-26/fat-bike-fat-x-26-inch-zwart-7-speed/

Cost EURO 400 / USD 470

Frame: Steel
Gear: Shimano STI 7 versnellingen
Brakes: Zoom disc brakes
Tires: 26" x 4.0

From em3ev:

Half Twist Throttle With 3 Speed and Cruise
Ebrake mechanical eBrakes

Mac 8t Fatbike 170mm freewheel 48v 1000W
52V 25.7Ah battery with 60A Smart BMS (14S9P)
6 Fet 25A 3077 Controller

fCA3-DPS, Cycle Analyst Ebike Computer
CA3 Cycle Analyst PAS Speed Sensor

26" Stars velg J57S with 13G Sapim spaken
Freewheel 7sp DNP 11T
DNP Extractor Tool (voor Freewheel montage)
Torque Arm Rear Rev4

Cost EURO 1335 / USD 1558 including shipping

Grand total: EUR 1745 / USD 2037

 

[SlowCo]

https://spaarbikes.nl/products-page/mountainbikes/vogue-maximus-fatbike-36-v-13-ah-8-sp-grijsblauw/

Of bovenstaande kant en klare fiets kopen en de controller hacken :wink:

 

[MaartenL]

That is boring! Besides less fast anyway

 

[electricwheels.de]

8T MAC on a 26" rim with 4" tyres? Why 8T?

 

[MaartenL]

Well, I was reading on their website about the specs:

6 turn high speed motor - 400rpm loaded at 36V, 520rpm loaded at 48V
8 turn standard motor - 320rpm loaded at 36V, 400rpm loaded at 48V
10 turn torque motor - 255rpm loaded at 36V, 320rpm loaded at 48V
12 turn low speed extra torque motor - 200rpm loaded at 36V, 250rpm loaded at 48V

Accepts disk brake and 7 speed freewheel with standard 135mm rear dropout.

As a guideline you can expect approximately the following real world speeds for the above windings on 12S LiFePO4 battery pack (approximately 38V under load) in a 26" rim on the flat, no pedaling with a rider plus bike weight of approximately 130kg total (286pounds):

6T - 45kph (36v), 65kph (48v)
8T – 39kph (36v) , 50kph (48v)
10T – 32kph (36v) , 40kph (48v)
12T – 25kph (36v) , 32kph (48v)
Spoke Radius - 172mm
Weight - 4.3kg

So I thought 8T would fit me best. Anyway em3ev doesn't offer the 6T option. More rpm = more power which seems logic for a Fatbike I like to take offroad.

 

[SlowCo]

So I thought 8T would fit me best. Anyway em3ev doesn't offer the 6T option. More rpm = more power which seems logic for a Fatbike I like to take offroad.

More rpm is less torque so less (not more) power but more speed. Which will be fine on pavement in our flat country. Although if you plan to use the fat bike (26" fat bike tire = appr. 29" outer diameter) on the beach or rough off road terrain the 8T might be a little too high rpm. As you plan to get a 14S battery which is 58V fully charged and put the hub motor in a fat bike wheel with 29" outer diameter I would advise you to get the 10T motor.
A rough calculation would see a top speed of 45 to 48 km/h. And I don't think you will like to ride that speed often on a non suspension fat bike with crappy brakes... :wink:
I even think you should get the 12T motor as the extra torque is much nicer to have than the slightly higher top speed of the 10T motor.

 

[MaartenL]

I think I settle for the 10T anyway. I get around 80 N-m of torque up to 12km/h which would be plenty. A little more topspeed is a nice bonus. So I also changed my rim towards the 26" Alex Blizzerk Pro 80 with 13G Sapim.

In the end it will be:

MBM FATBIKE FAT 26"
https://spaarbikes.nl/products-page/cruisers-26/fat-bike-fat-x-26-inch-zwart-7-speed/

Cost EURO 400 / USD 470

Frame: Steel
Gear: Shimano STI 7 versnellingen
Brakes: Zoom disc brakes
Tires: 26" x 4.0

From em3ev:

Half Twist Throttle nothing else (can control all by CA3?)
Ebrake mechanical eBrakes

Mac 10t Fatbike 170mm freewheel 48v 1000W
52V 25.7Ah battery with 60A Smart BMS (14S9P)
6 Fet 25A 3077 Controller

fCA3-DPS, Cycle Analyst Ebike Computer
CA3 Cycle Analyst PAS Speed Sensor

26" Alex Blizzerk Pro 80 with 13G Sapim spaken
Freewheel 7sp DNP 11T
DNP Extractor Tool (voor Freewheel montage)
Torque Arm Rear Rev4

Cost EURO 1386 / USD 1622 including shipping

Grand total: EUR 1786 / USD 2089

 

[SlowCo]

Cost EURO 1386 / USD 1622 including shipping

If you're lucky and don't have to (unlikely) pay import tax and BTW. Otherwise it will be a little higher...

 

[MaartenL]

So after reading more about pas sensors I decided to add a torque sensor from em3ev. They only offer the TDCM which seems like a good deal. I really like the idea of putting some effort in and getting a responsive return from my motor.

Do I still need a regular cadence pas sensor too? It's cheap but will I ever need it? Anyway I still have the trottle on my steer.

Ow and I was indeed looking for the Mac 12T now. 8T my first thought than 10T but I'm really liking the amount of torque more over speed. 35-40km/h is anyway enough for me.

 

[SlowCo]

Wise decision to buy a 12T. And I don't think you'll need PAS if you choose a torque sensor axle instead. Besides you also have a throttle you can use when not pedaling or to up the power over the torque sensor input.

 

[MaartenL]

So I bought a Dutch Fat Bike from Switzz Bikes!

Fat 8.1 specs:
Wheels 26"
Tires: Kenda Juggernaut Sport 26″x4.00
Frame: Aluminium 6061
Disc Brakes: Tektro Aquila Mechanical Disc
Gears: 8 Speed Shimano Clarius
Chain: KMC -72
Cassette: 8 Speed HG41

Dropout / HUB spacing / Axel for rear wheel: 197mm and Switzz says I need 220mm!
Bracket for midmotor: 120mm

So... what are my options?? EM3EV only has 170mm dropout HUB motors for rear.

I could go with a Mid Motor system but the Bafang BBSHD has some firmware problems as I understand.

What would be my best shot? I want something to ride on the road/beach/steep small climbs and with much torque / Nm. A topspeed around 40-45km/h would be enough.

For a middle motor: how much power do I really need vs when do I start to eat my chain / gears. I like to peddle and the PAS Torque sensor was my favorite option. However a throttle is nice to have!