Wanted: Lightweight (less than 20kg), high Torque (90NM), Motor offering large amount of power 500w+, removable large battery

You could look at wafabike's "I am urbanity". This bike is similar to the Luna Fixed (mid drive, belt drive and IGH). It weighs 18kg, but unfortunately you can't remove battery easily. The battery is quite small at 250W. You could ask wafabike about spare battery mounting options.


It has a Bafang M500 motor which is the same as the M600, but nominal power is limited be compliant with european regs so torque is less but still a respectable 95 Nm and has a nylon reduction gear so much quieter than the M600. Here are some comments on the M500 motor compared to the M600:

 
I think the biggest problem is the weight.. because 90Nm is not hard to achieve.

BBSHD has 160Nm so I was thinking about BBSHD kit with a relatively light bike, but even with custom build, I found it pretty hard to achieve that weight :confused:
My biggest obstacle seems to be the steep hills and getting the bike up our very steep hills. My arm is still in pain after trying to manage a 20kg bike on a trial last week.
Okay so, here's an alternative.

There's a company called Litespeed, they make titanium roadbikes.

According to the review, it weighs approx 15 lb 15 oz, so almost right on the edge.

🤔
I'll check them out. Budget wise i'm expecting to have to spend a few thousand pounds. I'd rather find the right thing than waste money not using something expensive.
 
With a BBS02 kit + road bike, I'm sure you can easily stay under the 20 kg limit.

My retro fitted 1987 Bianchi is a steel frame bike that has a Bafang BBS02 connected to a 13 ah 48v battery.

Previously it had carbon drop bars, Shimano 105 shift levers, and aero seat. That came in at 43 lbs.

Now with the riser bars, I'm guessing maybe 44 lbs, but you can offset some of it by removing the rear rack.

Before the kit, the bike weighed in around 25 lbs.

I'm not sure what the torque figures are but its been configured to run at 1200 watt peak.

IMG_20200511_125549.jpg

I also have a folding bike that is aluminum with a BBS02 kit + 6ah battery. That bike is heavier at 29 lbs stock, but with the smaller battery
it still comes in under 43 lbs. This little guy also runs at 1200 watt peak and on the road goes 36 mph (throttle only) using a 52t chain ring. It has enough
torque that in the lowest gear, the bike will run away from you if you apply too much torque. With the raised bars and weight distributed to the rear,
the folding bike torque is more noticeable.

I was not being careful one time and it almost threw me off the bike because the front wheel will easily lift off the ground from the torque.
Now I only throttle after the bike is moving a certain speed before ever using the throttle.

The bulky old screen is gone and replaced with a Luna mini display. Just haven't had a chance to get an updated picture.

IMG_20180920_205717.jpg

I also have BBSHD configured to 1600 peak watts on a 2017 Specialized Rockhopper but its much heavier and not as wild as that little folding bike
 
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What your asking for doesn’t really exist because high power and light weight are mutually exclusive. I also am assuming that you need fenders and a rack which add more weight.
Some suggestions. Don’t focus on the 90nm. Most of the torque numbers published are marketing hype and not directly comparable. So buy a light weight bike with a small motor and change out the front chain ring for something smaller. This will help with your big hill. But it will reduce your top speed, not sure if that is an issue. Another option is a cassette with a better granny gear that you can use for that steep hill.
You mention problems with walk mode. I can’t speak for all brands but walk mode should easily carry the bike and a heavy load on the bike up a steep hill. Specialized certainly can. I think the bike you tested may have had a defect.
Having said all of that you need to test ride the bike to ensure it meets your very specific needs. This will further limit your choices. Hopefully you have a good LBS to work with.
 
How much $ are you willing to pay?

There's an option to go titanium.
The PredecoTech Titanio is 31.8 lbs (14.42 kg), including the battery.

Hi Timpo, i'm expecting to have to pay around £3k-£5k. I'm not sure I fully understand the difference between the 250w and 500w. If 250 is enough to pull me nicely up the steep hills with the level of torque required i'll go with that. I haven't tried enough bikes to know the difference. I know I can lift 13kg up our stairs and the steps are verging on too steep to push a bike unless there is enough power in the walk assist feature to get the bike up.
 
This has a fauza evation motor which is a bit underpowered. While nominal motor output is 250W (they are all magically 250W nominal to comply with the regs), I think peak output is only 400W. Note Court's review of a bike with the fauza system he indicates:





I think if you went with a performance mid drive from one of the other motor brands you would be fine (even without 90nm torque) as they put out 500W (or more) peak power.



I believe these use rear hub motors which struggle on hills due to not being able to use the bike's gears and further handicapped by the 250W nominal limit in the UK. You will do much better with a 250W mid drive since it can leverage the bike's gears (unlike rear hub motors). In the US rear hub motors are more popular as they are inexpensive and the nominal limit is 750W so much more power can be delivered to offset the disadvantages on hills.
Thanks Tomdav, especially for the explanations. Starting to understand more as I read.
 
How much $ are you willing to pay?

There's an option to go titanium.
The PredecoTech Titanio is 31.8 lbs (14.42 kg), including the battery.

Hi Timpo, The weight of this is pretty close to what I know I can manage weight wise
How much $ are you willing to pay?

There's an option to go titanium.
The PredecoTech Titanio is 31.8 lbs (14.42 kg), including the battery.

This looks pretty close to the weight I can manage. What do you think about the power and torque for managing the steep hills and steps?
 
If you don't want to break the bank this might work. 22kg and cube sells a rear rack.

Nice bike and looks powerful but I can't lift 22kg. I can't find what it weights without the battery but i don't think it'd be close to 13kg.
 
It honestly sounds like you'd be a good candidate for the new Turbo Vado. Engine power and battery are down on your initial specs but it'd be worth taking a test ride. Unless you're planning on doing long half day rides I'd imagine the Vado battery would cope with the 15 mph UK limit just fine. And a mid drive is generally going to power up hills reasonably well if you have the gearing and energy to help it along.

 
Remove your torque requirement, those ratings are mostly gimmick that does not give a true indication of how strong the motor is. As long as the motor has enough power you can use the gears + slow down and easily climb most of the hills. How steep are the hills you are trying to climb?

My vote is also Vado SL. I think it may be the perfect bike for you.
 
She said she already tried a bike with fauza evation and I got the impression torque didn't meet her needs on hills so doubt the Specialized SL is going to work for her.
 
She said she already tried a bike with fauza evation and I got the impression torque didn't meet her needs on hills so doubt the Specialized SL is going to work for her.

She quite liked the Fauza equipped Focus' assist up hills. It just wasn't commuter friendly.
 
You guys are amazing. Thanks for all taking the time to try and genuinely help me work out how to find a solution. So the main thing i'm getting is that I may not need as much torque as I think I do for steep hills if the power on the motor is sufficient.
So, what i've found so far is this:
I tried a Cube Acid- pretty darn good in so many ways but struggled up the steep hills and is too heavy to lift up our steep 45 degree stairs into the house.
I tried Ezego- Pretty good too but struggled up steep hills (thanks for explaining fazua may not be as powerful as bosche/ yamaha etc) and whilst only 20kg it was heavy pushing it up the steps even with the walk assist. (The walk assist cut out but it was still awkward holding the button down at that angle)
I tried a Trek powerfly on a less steep hill but the power in it was awesome! Whilst tempted to get one it was a heavy bike that I couldn't lift at all up steps which almost rules it out sadly as i liked the power it had.
I tried a motus raleigh which was terrible up steep hills and heavy.

I tried a Focus Paralane2 - lovely and light and without the battery I could pick it up easily which was fab but it was a big sluggish going up the steep hills. This is where I guaged what I needed for torque since this was close to what I feel I need in terms of power, just it was lacking a little in terms of power on the hills. The torque was 60 or 70 i believe so something this light with more power on the hills would be ideal. Focus don't have a rack on that bike though and don't recommend putting one on and I need to have a rack for panniers.

I don't need to go up hills fast, just say between 10mph-12mphr
What do you think is closest to what I need?
Thanks again, you've all been SO helpful!
Aneesa, UK
 
She quite liked the Fauza equipped Focus' assist up hills. It just wasn't commuter friendly.
Hi there, just pasting where i'm at with finding the bike:
You guys are amazing. Thanks for all taking the time to try and genuinely help me work out how to find a solution. So the main thing i'm getting is that I may not need as much torque as I think I do for steep hills if the power on the motor is sufficient.
So, what i've found so far is this:
I tried a Cube Acid- pretty darn good in so many ways but struggled up the steep hills and is too heavy to lift up our steep 45 degree stairs into the house.
I tried Ezego- Pretty good too but struggled up steep hills (thanks for explaining fazua may not be as powerful as bosche/ yamaha etc) and whilst only 20kg it was heavy pushing it up the steps even with the walk assist. (The walk assist cut out but it was still awkward holding the button down at that angle)
I tried a Trek powerfly on a less steep hill but the power in it was awesome! Whilst tempted to get one it was a heavy bike that I couldn't lift at all up steps which almost rules it out sadly as i liked the power it had.
I tried a motus raleigh which was terrible up steep hills and heavy.

I tried a Focus Paralane2 - lovely and light and without the battery I could pick it up easily which was fab but it was a big sluggish going up the steep hills. This is where I guaged what I needed for torque since this was close to what I feel I need in terms of power, just it was lacking a little in terms of power on the hills. The torque was 60 or 70 i believe so something this light with more power on the hills would be ideal. Focus don't have a rack on that bike though and don't recommend putting one on and I need to have a rack for panniers.

I don't need to go up hills fast, just say between 10mph-12mphr
What do you think is closest to what I need?
Thanks again, you've all been SO helpful!
Aneesa, UK
 
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