So I have been riding a Haibike hard tail with Bosch Performance Line CX motor and 500Wh battery for almost two years now.
Not too impressed actually. Some quality issues and the spare parts are very expensive. Plus the fact that you are bound to Bosch and their stuff. I have had another bike with cheap Aliexpress front hub motor for some years and very satisfied with that so I started to think....
Time to upgrade to a DIY-MTB with Bafang BBS01 250W 36V and shark battery pack. Just that I had no bike for it.
What I really wanted was some factory made mid motor frame. Such as Bafang Max-drive or the upcoming Bafang M500 system. Seems to take long time for that new system to hit the market though and I don't like waiting so I made some research trying to find a good object.
First I found a full suspension bike with threaded bottom bracket but the shark battery pack didn't fit so good there. So then I searched for a hard tail again, plus sized tyres. Many options come across, the two best was Kona Big Honzo and Trek Roscoe. The first was a little too expensive to convert I thought and the second was very good but had some things on the down tube right where you should mount the battery. So... I then came across my local tool stop and they had a new model this year. A plus sized bike that was the perfect object. Lots of space for battery and square tubes, threaded bottom bracket, dirt cheap!
Only matter was the rear hub. It was a freewheel 7-speed. With 148mm QR!! Very odd. So I had to change the hub to something modern to take a cassette. Bought a Hope Pro 4 Boost with QR-endcaps, 141mm. Combined with Hope fatsno QR-axles that I cut and threaded a little more to fit good. Used stock spokes but with new brass nipples.
The rear triangle is a little wide now (7mm) but I let it be for now, just have to press together a little when assembling the wheel.
Fitted a 10-speed cassette, 11-46T. Front chainring 35T, a standard 104 BCD on a Precialps Bafang-adapter.
New brake handles and shifter. Used Bafang stock brake handles and new shifter.
Will be using stock components as long as possible, saddle, stem, steering bar, brakes.
Crank arms though was a close one. The left is like 2mm from the chain stay. Tried stock crank arm on the left side only but Bafang has them 45 degrees wrong! So stupid to change the default pattern. But well, it works, just a close one here and something to consider when buying new crank arms. I was thinking if I am to correct the width of the rear triangle I do it only on the left side
problem solved.
Battery then. Since I ride rough terrain sometimes I want it sturdy mounted. So I drilled holes in this metal part of the holder and then drilled one hole in the frame for a nut rivet in the upper mouting hole. Then for sideway stability added triangular shaped black painted oak wood bars with adhesive mounting tape. You can also see the yellow XT60 connector for the battery mount. Used that this time for easy and safe connection.
And the result is this then, I have, besides new crank arms also my own pedals. And mud guards added. Otherwise stock.
You can see the Bafang motor has actualy quite good angle I think, I have seen many bikes with the motor more downwards, this is more upwards, better ground clearance. But I have to add some protection plate anyway because I hit a rock on the second ride even though I was careful.
Upcoming upgrade is a dropper post. And later 180mm brake discs because I need one 160mm for another bike so instead of buying a new 160mm I steal one of these and put on a new 180mm instead but the brakes is actually quite ok now anyway.
Fork is some cheap coil fork. It works quite good though but the rebound is terrible, it hits the bottom when fully rebound, such as a small jump. Quite anoying. I also have to adjust the preload a little more I think. On the positive side I feel that this fork should be quite troublefree if it just last long. Minimum maintenance, just ride! Until it brakes, then I can buy something flashy. And if the frame brakes I just buy a new frame of some kind and move everything to that frame.
Standard procedure with those cheap battery packs is open up and secure the build with dampers and inspect soldering. It doesn't look nice mostly. This was actually quite ok but needs some dampers to last on the trails.
So I have been riding it this week and are very positive.
It is a very different feel from the Bosch CX. First impressions was that it is quite weak in comparison but very quite (I did grease the main cog inside there a little as many say is a good idea). But after some riding I feel the power is enough. You don't fly uphill like on the CX in turbo mode. This is more like riding the CX in trail mode. But quieter, I guess that fools you, it doesn't feel as fast when it is so silent. No torque sensing, which doesn't matter too much I feel, on this 250W model, guess it is more important on the stronger ones. This is only 60 Nm (I think?) compared to 75 Nm on the Bosch CX, and I have a feeling Bosch numbers are underrated and Bafang might be the opposite.
Only thing is that when shifting, if you let off the pedals for a second to shift, the drive continues like two seconds before cutting. So that means if you shift and let of pedals for a blink you have the drive on the shifting, but it shifts ok anyway, at least now when the drive train is new guess it might be another deal after a while.
But I feel this drive train will last longer than if you had Bosch CX, it eats drive trains for breakfast. If you don't ride in lower assist modes.
Other positive thing is that it is quite light, the Bosch CX is heavy piece of equipment. This whole bike is not too heavy actually, aluminium frame and all. Feels quite agile even though it is an eBike.
I am very impressed with the Bafang BBS01 drive but the thing that impressed most is the battery time. I have some cheap Hercules battery from Aliexpress, 36V 20Ah. I thought that capacity was quite overspeced perhaps but today I was riding trail and some gravel, but mostly trail. For 30.5km (19 miles). I charged the pack to 41V (like I use to do, not full 42V). And the battery meter stayed full almost to the end, only on the last km it started to flash the first bar! Ridicilously riding times I get on this bike! Can do a really long tour if I want. My other bikes would sing on the last chorus by then but this one has barely warmed up!
Well. I am very impressed! Only hope that things will last. But I guess some things will happen, but that's ok, I'm not getting the creeps for servicing a bike like this. It is just fun
So this was my "upgrade" to this new rat bike it fits me well this, look forward to further adventures. Here is some photos from todays trailing:
Not too impressed actually. Some quality issues and the spare parts are very expensive. Plus the fact that you are bound to Bosch and their stuff. I have had another bike with cheap Aliexpress front hub motor for some years and very satisfied with that so I started to think....
Time to upgrade to a DIY-MTB with Bafang BBS01 250W 36V and shark battery pack. Just that I had no bike for it.
What I really wanted was some factory made mid motor frame. Such as Bafang Max-drive or the upcoming Bafang M500 system. Seems to take long time for that new system to hit the market though and I don't like waiting so I made some research trying to find a good object.
First I found a full suspension bike with threaded bottom bracket but the shark battery pack didn't fit so good there. So then I searched for a hard tail again, plus sized tyres. Many options come across, the two best was Kona Big Honzo and Trek Roscoe. The first was a little too expensive to convert I thought and the second was very good but had some things on the down tube right where you should mount the battery. So... I then came across my local tool stop and they had a new model this year. A plus sized bike that was the perfect object. Lots of space for battery and square tubes, threaded bottom bracket, dirt cheap!
Only matter was the rear hub. It was a freewheel 7-speed. With 148mm QR!! Very odd. So I had to change the hub to something modern to take a cassette. Bought a Hope Pro 4 Boost with QR-endcaps, 141mm. Combined with Hope fatsno QR-axles that I cut and threaded a little more to fit good. Used stock spokes but with new brass nipples.
The rear triangle is a little wide now (7mm) but I let it be for now, just have to press together a little when assembling the wheel.
Fitted a 10-speed cassette, 11-46T. Front chainring 35T, a standard 104 BCD on a Precialps Bafang-adapter.
New brake handles and shifter. Used Bafang stock brake handles and new shifter.
Will be using stock components as long as possible, saddle, stem, steering bar, brakes.
Crank arms though was a close one. The left is like 2mm from the chain stay. Tried stock crank arm on the left side only but Bafang has them 45 degrees wrong! So stupid to change the default pattern. But well, it works, just a close one here and something to consider when buying new crank arms. I was thinking if I am to correct the width of the rear triangle I do it only on the left side
problem solved.Battery then. Since I ride rough terrain sometimes I want it sturdy mounted. So I drilled holes in this metal part of the holder and then drilled one hole in the frame for a nut rivet in the upper mouting hole. Then for sideway stability added triangular shaped black painted oak wood bars with adhesive mounting tape. You can also see the yellow XT60 connector for the battery mount. Used that this time for easy and safe connection.
And the result is this then, I have, besides new crank arms also my own pedals. And mud guards added. Otherwise stock.
You can see the Bafang motor has actualy quite good angle I think, I have seen many bikes with the motor more downwards, this is more upwards, better ground clearance. But I have to add some protection plate anyway because I hit a rock on the second ride even though I was careful.
Upcoming upgrade is a dropper post. And later 180mm brake discs because I need one 160mm for another bike so instead of buying a new 160mm I steal one of these and put on a new 180mm instead
but the brakes is actually quite ok now anyway.Fork is some cheap coil fork. It works quite good though but the rebound is terrible, it hits the bottom when fully rebound, such as a small jump. Quite anoying. I also have to adjust the preload a little more I think. On the positive side I feel that this fork should be quite troublefree if it just last long. Minimum maintenance, just ride! Until it brakes, then I can buy something flashy. And if the frame brakes I just buy a new frame of some kind and move everything to that frame.
Standard procedure with those cheap battery packs is open up and secure the build with dampers and inspect soldering. It doesn't look nice mostly. This was actually quite ok but needs some dampers to last on the trails.
So I have been riding it this week and are very positive.
It is a very different feel from the Bosch CX. First impressions was that it is quite weak in comparison but very quite (I did grease the main cog inside there a little as many say is a good idea). But after some riding I feel the power is enough. You don't fly uphill like on the CX in turbo mode. This is more like riding the CX in trail mode. But quieter, I guess that fools you, it doesn't feel as fast when it is so silent. No torque sensing, which doesn't matter too much I feel, on this 250W model, guess it is more important on the stronger ones. This is only 60 Nm (I think?) compared to 75 Nm on the Bosch CX, and I have a feeling Bosch numbers are underrated and Bafang might be the opposite.
Only thing is that when shifting, if you let off the pedals for a second to shift, the drive continues like two seconds before cutting. So that means if you shift and let of pedals for a blink you have the drive on the shifting, but it shifts ok anyway, at least now when the drive train is new
guess it might be another deal after a while.But I feel this drive train will last longer than if you had Bosch CX, it eats drive trains for breakfast. If you don't ride in lower assist modes.
Other positive thing is that it is quite light, the Bosch CX is heavy piece of equipment. This whole bike is not too heavy actually, aluminium frame and all. Feels quite agile even though it is an eBike.
I am very impressed with the Bafang BBS01 drive but the thing that impressed most is the battery time. I have some cheap Hercules battery from Aliexpress, 36V 20Ah. I thought that capacity was quite overspeced perhaps but today I was riding trail and some gravel, but mostly trail. For 30.5km (19 miles). I charged the pack to 41V (like I use to do, not full 42V). And the battery meter stayed full almost to the end, only on the last km it started to flash the first bar! Ridicilously riding times I get on this bike! Can do a really long tour if I want. My other bikes would sing on the last chorus by then but this one has barely warmed up!
Well. I am very impressed! Only hope that things will last. But I guess some things will happen, but that's ok, I'm not getting the creeps for servicing a bike like this. It is just fun
So this was my "upgrade" to this new rat bike
it fits me well this, look forward to further adventures. Here is some photos from todays trailing: 
