Qulbix Q140MD - any experience?

It weighs 53kg :) Half the weight of a regular dirtbike, and twice the weight of a regular e-bike / pedelec. Matches the power and handling really, midway between a dirtbike and a bicycle in every way.
 
Another spring ride today, down what I thought would be a snow free gravel road which turned out to be covered with 10cm of slush / ice! The bike is amazingly easy to handle though, but I did have some trouble keeping the front wheel pointed in the right direction as it kept sinking down through the slush and tracking off to the side.





 
Thanks! Was a bit of a mission getting up those hills, but lots of fun too ;) No way a regular pedelec would have gotten up there, pedalling would have upset the bikes balance way too much and resulted in skidding the front out.

I did a bit of testing when I got back to see if I could tune out one aspect of the throttle response that has annoyed me. Basically, if you reach a bit of speed, and shut off the throttle, it will go to zero amps and coast along nicely as it should. But if you slowly roll on the throttle again it will apply negative amperage (i.e. regen braking) until your speed matches your throttle input. Very different from a motorbike, so I had to sort this out.

Qulbix suggested I test three parameters in the app for the KLS 7230 S controller, and here are my results:

Accel Time: Default is 1 - This is just the time it takes to ramp up the motor response when you get on the throttle. Kind of affects the regen, but only in so far as it slows down all throttle response. Not the right option for me.

Torque Speed Kp: Speed percentage supposedly, default is 5000 - this made very little sense to me, setting it to 1000 resulted in very little acceleration, setting it to 8000 made very little difference at all compared to stock. No change to the regen.

Torque Speed Ki: Speed integral, default is 30 - setting this to 15 first, then 2, and then 0, seemed to improve things quite a bit. I still get a tiny bit of regen after coasting, but much much less than I used to do, and it no longer upsets the bike as you transition from rolling to accelerating. Problem solved (well, 99% gone).


I don't understand why there isn't a setting in the controller software that simply tells it to never do any regen braking unless I specifically request it via the regen brake lever, but I can't blame Qulbix for that - might send a suggestion in to Kelly Controllers ;) I would also love to see the control loop calculations and where these parameters actually fit in, but I somehow doubt they will send them to me :p
 
SlowCo said:
Beautiful place for riding. I'm jealous! :mrgreen:
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Thanks! Norway has some fantastic nature, and I live in the "boring" bit around Oslo, the west coast is far more majestic. We get much better weather though, so there is that ;)

This season is going to be amazing, I can't wait to explore all these trails that have been off limits while I've been riding motorbikes! I met quite a few people who were out walking (and skiing!) on this road yesterday but they only smiled and said hello :) Had I been on a motorbike they would not have been anywhere near as friendly... (and I would have been breaking the law!).
 
SlowCo said:
I suspect your BMW will be used a "little less" coming season :wink:
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I actually sold it :lol: Pretty much all my forest and proper off road and trail riding will be done with this e-bike. Being able to silently cruise through the forest is just a dream come true for me! That said I did also buy a new KTM 690 Enduro R for tearing it up down gravel roads when the need for speed becomes overwhelming ;)

I had a bit more time to play with settings while practicing wheelies today, and discovered a couple of things. The "Accel Time" setting, while not affecting the regen issue, was actually quite useful to adjust. The default is 1, which makes for 0.1 seconds of lag between throttle input and result which feels very brutal when you are used to a petrol engine that takes a little bit of time to get the message. Setting it to 3 (0.3 seconds delay) was much more familiar and makes the bike, even in full power mode, feel much easier to control.

Secondly, and perhaps most interestingly, I found out that the regen issue (regen when rolling on the throttle after coasting), is only there in Eco mode! It is not present at all in full power mode. Very very strange, and seems to indicate that Eco mode turns on some form of speed control in addition to the torque control from the throttle. I have no idea how to get around this, reckon I will need to get in touch with Kelly Controllers directly to find out what is going on in that mode.

I could always just ride in full power all the time, but having the mellower power delivery and 25 kph top speed from Eco mode is very nice when I'm trying to ride in a responsible and legal manner. The whole ride yesterday was in Eco and I never felt like I needed more power.
 
A video of me trying to wheelie :p It also show an acceleration run, uphill, where I had to back off the throttle to avoid wheelies/wheel spin. This thing is insanely fast in full power mode!

[youtube]YLwC8k-3k5M[/youtube]
 
Good for you.If we would have snow in Hungary I would drift it in snow all day for sure.
Mine is in service right now :( I had to send the rear wheel to Qulbix so they can rebuild it because the hub gave up after only 1200km.Poor quality what can I say..Hopefully they will replace it with a better one.
 
I just got an e-mail from Qulbix saying they wanted to replace my rear hub with a new one as a precaution, probably because of the incident you experienced. Sucks when stuff like this happens, but it's nice to see that Qulbix are taking it seriously and fixing it all under warranty :) With a bit of luck I will have my bike back in one piece before Easter - there's still too much snow to do any proper riding in the forests here anyway. It will cut into my wheelie practise though!

If it's any comfort my brand new KTM 690 Enduro had a recall issued on it before they even had a chance to deliver it to me - so it happens even to the bigger manufacturers ;)
 
A size comparison for those who are interested. I got a few comments both online and from friends that there was no way the Qulbix would pass as a bicycle, it looked far too much like a motorbike. I almost started to get worried until it actually arrived ;) What most pictures don't show you is the scale!

Here are a couple of shots of it next to my KTM 690. The Q140MD is tiny by comparison, and even though it is stood closer to the wide angled lense of my mobile phone in these pictures you can see both the height difference and the overall mass difference between the two bikes.





 
icherouveim said:
So which one is better? Which one Do you love most? Big or small?
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That's a good question! And a difficult one to answer, so I'll have to get a bit hypothetical.

1) If I had to choose one now, I would keep the e-bike as my main love is forest riding and single track, and that simply isn't legal here in Norway on the 690 (to the point where I would very likely end up having it confiscated). The Q140MD is also really great fun to ride on technical stuff, and it is helping me learn to wheelie ;)

2) If I could legally ride the 690 where I want to ride, I would choose that due to the versatility and range. It can do motorway stints, and single track, and can keep going for over 200 kilometers and refuel in a few minutes. Having experienced the joy of silent electric power I would certainly miss that, but the versatility would win.

3) My dream bike? An electric 100kg dirtbike, totally silent, with a 200km range. Alta Redshift is the closest anyone has got so far but they are a bit noisy, have too little range, and have gone bust unfortunately!
 
Oh, and I have to add, if I wasn't worried about the legal side of things and trying to keep the e-bike as bicycle-like as I can, then I would get it with the moto-seat and the footpegs. I have ridden motorbikes for 20 years, so the pedals and bicycle seat do feel kind of strange to me, and I can't grip the bike properly with my legs like you can with a motocross bike.

I might still end up ordering the moto-seat and peg kit and swap over if I've got a day on the enduro / motocross track planned ;)
 
icherouveim said:
So Do you ride from the age of 15 years old? :shock:
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Got my license at 16, spent the year before learning to ride and riding around private land (and my neighbourhood) as much as possible ;) So yeah, almost 20 years of riding experience from motorbikes, but sadly I didn't understand that off road riding was amazing before the last 5 years. At that point I bought a KTM 500 EXC and every bike since has been mainly aimed at off road trail riding :)

Contrasting that I think I have spent maybe a handful of hours on a bicycle during that time, and the last time I tried downhill mountainbiking I ended up in hospital :p Thankfully the Q140MD handles more like a mini-motocross bike than a bicycle, and the pedals are really only there for pedalling along nicely kept gravel roads. Once the terrain gets tricky with roots, rocks and hill climbs I forget about the pedals entirely and treat it like a motorbike.
 
This is probably my dream ebike frame, I need to move to mid mount but the noise and complication with setup like dealing with chains, rings, and different controllers makes it difficult. Even with a hub motor weighing just 16 lbs in the rear wheel, you can really feel it bogging down the rear suspension offroad.

I just wish it wasn't so damn expensive, and you have to buy the whole bike too. That doesn't really jive with the DIY endless sphere community does it? maybe we can get a group buy together for just the frame, rear wheel, and chainrings for the motor and wheel? oh and maybe the custom pedaling chainrings too...
 
There are so many custom parts in this thing I don't think it would make for a very good DIY project to be honest, unless you have access to a machine shop / CNC machine. Packaging a hub motor as a mid drive motor sounds easy but when you consider the whole motor rotates and the center of it is stationary it becomes a whole lot more difficult. I do wonder if QS motors could do a mid drive version where the wiring goes in to the outside and the hub is the drive.... would make it a lot easier to build a bike around!

As for the cost, I was going to buy a motocross bike and ended up with this instead, saved me about 4k :lol: All depends on your frame of reference I guess ;)
 
I designed a simple CA mount. The one the bike came with just didn't look right and I had to take it off every time I had to flip the bike upside down.I printed it with a 3D printer with ABS at 90% infill.
https://drive.google.com/file/d/1fkpPaenN7pSFyqvljJFsjxGh3TRbX8fc/view?usp=sharing
i94M5BN.jpg

LWfeIvq.jpg
 
That looks very neat! Might try to make something similar from aluminium flat bar as I don't have access to a 3D printer, but I do have a drill-press :)
 
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