The BEST and FIRST Qulbix Raptor mid-drive build!

Dear Mike,

Many thanks for your detailed information. You made me realize something I was not yet aware of! As you might know, the Zero motorbikes do also have that giant rear sprocket, and made it happen. That's where my inspiration came from.

Interesting to see the primary and secondary idea. So the chain basically reduces ratio near the motor sprocket, and the drivetrain is belt driven to the rear wheel, right?

Last question; are the chain sprockets commercially available, or is is necessary to make these custom?

Many thanks,

Bart
 
Rgarding the belt drive Lightningrods has explained it very well.
If you want to transfer a large force over a belt, the sprockets must be huge. The other downside is the price. Custom made pulleys are very expensive because of the tooth profile which is quite complex to produce, while kart chain sprockets up to 100teeth are available on the market for cheap.

I am doing a middrive conversion on one bike which was powered by a hubdrive before. I decided to went with a belt drive willing to take all the effort and costs it will take. The motor should be similar to the LR BigBlock in terms or power.

If someone is interested about my mid-motor belt drive thats the thread:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=91144
 
Toothed belts are great for high RPM, low torque applications. Chains work best in low RPM, high torque applications. This is why two stage reductions tend to be belt on the first stage and chain on the second stage. The belt is more efficient and quieter which is perfect for the first stage, while the second stage operates at a far lower RPM, but higher torque making a chain a better choice.

Matt
 
Dear madin and recumpence,

Thanks for your additional supportive information regarding belts.

The last question about the availability of sprockets might have been formulated not clearly enough; it was a question about a chain and sprocket setup: are as well the front as the rear sprockets, with a 8:1 reduction like Lightningrods has build with his q76r swingarm setup: are they commercially available? If so: at which price range are they?

These questions popped up since I am finally calculating the maintenace costs before deciding the new motor setup.

Thanks in advance!

Bart
 
LightningRods said:
Thanks for all of the feedback. I currently build three drives that will fit the Qulbix frames.

#1- Two stage bottom bracket drive.



#2- One stage bottom bracket drive.



There are advantages and disadvantages to each one. The two stage drive is best for steep climbing, pedaling with the motor, extending battery range. The one stage is best for going fast, moderate climbing, running over 3000 watts through the bike gears. The swingarm drive is meant to be as simple as possible. Many people avoid mid drives just because of the number of moving parts. The swing arm drive is an alternative to hub motors that is lighter, has reduction gearing, and is positioned close to the fulcrum point of the swing arm.

Do you sell them as a kit ? im interested running 72v through a cyclone on a Q76R frame..
 
I have a bottom bracket drive that will fit a Cyclone 3000 watt to a Q76. With a little work it would probably be possible to run the Cyclone on the left side and avoid the typical shredding of bicycle sprockets on the right. You’d have to give up the freewheel on the motor but that’s not really a bad thing since it’s another weak spot.
 
Hi Mike, Are you still around and building? These threads seem quiet. Im curious about the Q76 swingarm drive. A while back, you mentioned that it could be set up with the small block , allowing room for a derailler. Is it still possible? Can a freewheel cluster screw onto your hub? And (for now) What is the flange width on that hub? Been learning and building hub motor bikes now for 4 years and finally realized that i need to turn all my hubmotors into drift trikes. Your stuff is all great, but the simplicity of the swingarm drive and hub has me droolin. thnx doug
 
Hi Doug,
Yes I’m still around and still building. I’ve been on my Facebook page a lot and not on E-S so much. If you want to keep up with what I’m doing pretty much every week the link to my Facebook page is in my signature at the bottom of this post.
The first batch of hubs that I had made are spaced for a single speed freewheel. The best pedaling option is a SpeedDrive two speed planetary front chain wheel. With it’s 2.5:1 overdrive you have a 20 mph low gear and a 50 mph top gear. With at least 3000 watts on tap pedaling is just for exercise.
If you want a cassette the best way to make that work is to buy a narrower cassette and use rotor and axle spacers on the left end. The 160mm width Quilbix swing arm provides the best spacing for the swing arm drive. A 150mm freehub should allow enough room to have both the driven motor sprocket and rotor on the left side.
One of my customers is running the swing arm drive at nearly 100v and hitting speeds in the mid 60 mph range on his Q76. He decided to go to foot pegs to make the bike more stable at speed.
Cheers,
Mike
 
Wow. Just read this thread from start to end in about 2.5 hours. Good stuff all around and awesome to watch the development of LR's drive systems.

I've been building ebikes for awhile now and just branched out into building them for others after I got a request from a customer. Will definitely be using a LR big block, and probably chain tensionser, hub, and some other parts from LR. Thinking about a Qulbix76 with 19in moped rim in the front and 17in in the rear. Anyone have weights on their finished Q76 builds? Customer is looking to stay below 80 lb with somewhere around 72 V 20Ah battery.
 
Hi Mike , Back here again. I couldn't drag notes on facebook so.... Thanks for reply, I might not understand what you told me:

With at least 3000 watts on tap pedaling is just for exercise.

I want to travel, so I looking to miser some watts
This is what I don't understand:


If you want a cassette the best way to make that work is to buy a narrower cassette and use rotor and axle spacers on the left end. The 160mm width Quilbix swing arm provides the best spacing for the swing arm drive. A 150mm freehub should allow enough room to have both the driven motor sprocket and rotor on the left side.

Do you have a 150mm version of your hub? Or are you referring to a regular bike hub?and if so, how to mount your 96 tooth sprocket(essential). Your hub looks bulletproof so I would really like to use that with your big sprocket. Also much easier to use a system that you've already worked out . Don't want to offend , but would it be possible to cut the hip ( that the freewheel screws up against) in an 1/8 inch to accomidate a slightly larger freewheel? I see some 3 spd freewheels that are probably just a couple MMs larger than the single . I know theyre junk but I wont be shifting for speed. Just so they shift

Also, do you have a source for that 2.5 to 1 chainwheel? THNX Doug
 
Hi Doug,

Yes I was referring to buying a mass produced freehub that's undersized. You would have some things to work out in order to get all of the spacing correct. The brake rotor is the most critical bit. My hubs are a lot more sturdy and have sealed motorcycle type wheel bearings rather than bicycle cone bearings. I only have a 165mm version of my hub. It fits the wider Qulbix swing arms and the EEB with my horizontal dropout plates. The 96t 219 sprocket has a standard 6 bolt brake rotor pattern. It will also bolt to a regular manufactured freehub.

It looks like a 3 speed freewheel would fit my hub. Space outboard of the threads is very limited but there is a ton of space inboard which is where the extra sprockets seem to be located. I didn't consider these Chinese freewheels because, as you said, they are garbage. But they should fit. I'm not completely sure that the outermost sprocket would allow the chain to clear the frame. It looks tight.

3SpeedFW.jpg


EEB swingarm with my horizontal dropout extension plates, 165mm hub, and billet brake caliper mount.

EEBSwingarm.jpg


I bought my SpeedDrive from Vad at PowerVelocity. At that time we couldn't buy direct from SD in the US. I don't know if this is still true. I have one brand new in stock which I'll sell for less than the direct price. I bought a 100mm spindle thinking I'd build an EEB and then built a Q76 which has an 83mm.

Cheers,
Mike
 
I really like this system on Qulbix frame as the motor is nicely nested and don't hang low like on EEB frame.
I wonder why there aren't people who has it, here in the topic. I cannot find any review nor video about it. What concerns me is how noisy this setup is.
 
The motor on the EEB actually is very close to the same height as on the Qulbix. The reason that it looks like it's lower is that the bottom bracket and chainring on the EEB sit way higher than the Qulbix. I'll attach a graphic that shows the layout of the two bikes in comparison with swingarm drives installed.

This drive isn't noisy for a mid drive. It's louder than a quiet hub motor but unpleasantly noisy. I was relieved when I first ran the bike because I knew it would be compared to hubs. If silence is your top priority, buy a hub. If everything else is your priority, buy a mid drive. A single stage swingarm drive like this is as simple as a mid drive can be.

I'll make some videos of my own once the weather improves. I'm developing yet another drive for the Qulbix frame but I'll take a bunch of photos and some videos of this swingarm drive in action before I decommission it.

Enduro-Qulbix.jpg
 
Thank you for clarification and example. It seams those two frames are very different to pedal because of that (ignore the width difference). Can you please share your opinion on that natter as you have tried them both.
Low noise is my very high priority but hub is out of the game because of the purpose of the bike, so I thought to go with BBSHD if this system is very noisy. I would at least like to hear how it sounds indors.
 
I personally prefer the Qulbix over the Enduro. The pedaling position is much better on the Qulbix and the build quality of the frame and especially the swingarm is on a much higher level. The Qulbix is a couple hundred more and well worth the extra money.

The Bafang HD is a nice pedal assist and it works well on bicycles. It doesn’t belong on a heavy duty battery box bike like the Qulbix or Enduro. All of that extra metal in the construction of these bikes makes them strong enough for large powerful motors but too heavy for small pedal assists. Qulbix had a BBSHD model briefly and then discontinued it. The big block is twice the motor that the BBSHD is. Remember more than a third of the Bafang is planetary reduction. The big block is all motor.

No mid drive that reduces motor rpm to human pedaling speed and then overdrives back up to a higher wheel rpm is a “high power” mid drive. Especially not through bicycle sprockets and chain. The 219 kart chain that I use is good up to 15kW. Bicycle drive lines start to fail around 3kW.

The Bafang has a planetary reduction, which even with weak nylon gears makes noise. Then it has a secondary ring gear reduction to the chainwheel. The big block is a large low kv motor that drives directly to the rear wheel in one stage. You hear the motor and the driver sprocket on the chain. The large rear sprocket is nearly silent. Now that I have a 3D printer I’m going to make an enclosure for the driver sprocket that will make it quieter and keep chain lube from making a mess. I already did this on my single stage drive and it was a big improvement.
 
LightningRods said:
I'm developing yet another drive for the Qulbix frame

Enduro-Qulbix.jpg

What do you have in the works Mike?
 
Thank you very much for your input.
I was thinking Qulbix Q76, not Q140 frame, which is 8.1kg.
I have seen one Q76 build in YT video... seams pretty agile. I now live in Germany, and they seams pretty strict with regulations, so I was thinking less noise could help me not to attract too much attention. Everybody rides ebikes here and all are completely silent so it is hard to blend. Another plus would be integrated controller so no extra space is needed.
 
devo1223 said:
What do you have in the works Mike?

Two stage left side drive, new motor, not on swingarm, ASI BAC4000 controller, shooting for 25kW. :twisted:
 
One thing is not clear to me... does this setup has a freewheel? I don't see any. If not, how is even possible to pedal without motor running? I expect resistance from motor is too big.
 
This drive has no freewheel to break. Because of that it’s compatible with regen braking.

I realized early on that my customers were in two groups: people who want to pedal and people who don’t. Pedelecs like the Bafang are designed to be low powered drives that the rider can pedal with. That’s what they do well. Drives like this swingarm drive have pedals mostly to qualify as an electric bike rather than a lightweight electric motorcycle.

The Qulbix is a poor choice for a pedal bicycle. It’s miserably heavy to pedal. I would never put a Bafang on a Qulbix or EEB frame. If I wanted a mid drive Qulbix I’d either buy their version (which they made after they abandoned their Bafang version) or one of my drives. The Qulbix and EEB are also poor choices for restrictive areas because they look more like a motorcycle than a bicycle.
 
LightningRods said:
Two stage left side drive, new motor, not on swingarm, ASI BAC4000 controller, shooting for 25kW. :twisted:

Sounds interesting! Any updates you ever circle back around to this project?

Putting together a new Qulbix 140 build this fall. I've got a BAC4000 on order (if they ever ship it) and I'm planning on building the battery to match the controller throughput. I want to make sure I pick a motor that takes advantage of the high current. I'm torn between a QS205 and a LR mid drive. For now it will be used used 90% on road and noise is a concern. I think the QS205 is a more appropriate choice but I've never owned a mid drive and the LR kit build quality looks so high (been eyeing your kits for years)! Thoughts?
 
Where we are right now is running the Big Block with the brand new BAC2000 that puts out 230A peak. Acceleration and hill climbing are very impressive. Top speed is presently gearing limited to the mid 50 mph range. It’s a kick in the butt!
If all you are going to do is straight line commuting and stealth is a high priority, a hub motor is not a bad choice. You will need about twice the current and twice the Ah in battery for the same performance and range. This is where you pay a big price with a big hub. They’re very inefficient compared to a mid drive and need a big, heavy, expensive battery (and matching controller) to get the job done.
The biggest advantages of a mid drive are cornering balance and suspension compliance. If you’re just zooming along in a straight line on smooth pavement that may not matter to you. To me hub motors are cruiser or flat country commuter setups. They’re quiet, mostly low maintenance, and there is less to think about.


pjwalmsley said:
LightningRods said:
Two stage left side drive, new motor, not on swingarm, ASI BAC4000 controller, shooting for 25kW. :twisted:

Sounds interesting! Any updates you ever circle back around to this project?

Putting together a new Qulbix 140 build this fall. I've got a BAC4000 on order (if they ever ship it) and I'm planning on building the battery to match the controller throughput. I want to make sure I pick a motor that takes advantage of the high current. I'm torn between a QS205 and a LR mid drive. For now it will be used used 90% on road and noise is a concern. I think the QS205 is a more appropriate choice but I've never owned a mid drive and the LR kit build quality looks so high (been eyeing your kits for years)! Thoughts?
 
Hey mate - are you able to share the method for making a 219# sprocket profile? Ive got a few different sizes im looking to cut, any help appreciated cheers mate.

toolman2 said:
LightningRods said:
ElectricGod said:
...what can't this hub do?

"That's right, it filets, it chops, it dices, slices,
Never stops, lasts a lifetime, mows your lawn
And it mows your lawn and it picks up the kids from school
It gets rid of unwanted facial hair, it gets rid of embarrassing age spots,
It delivers a pizza, and it lengthens, and it strengthens
And it finds that slipper that's been at large
under the chaise lounge for several weeks
And it plays a mean Rhythm Master,
It makes excuses for unwanted lipstick on your collar
And it's only a dollar, step right up, it's only a dollar, step right up"
-Tom Waits, "Step Right Up"

Sorry. Every time I feel tempted to go into a sales pitch I think of this great song and how much I loathe pitch men and advertising.

My machinist is stoked about making hubs for ebikes. He's been very cooperative about making parts up until now but this really has him lit up for some reason. It is a pretty part.

My plan is to offer variations of six bolt disc brake flange mounts, freewheel threads, and freehub mounts in various widths. The narrower hubs are going to be more challenging in terms of fitting two left side flanges, but I have some tricks up my sleeve for those. I'm also making #219 sprockets with a five bolt freewheel pattern and the six bolt disc brake flange pattern. Those are either hard to find or didn't exist before.

I like it LightningRods, good plan for hubs. #219 is awesome, and capable or 400NM to the ground if you keep the tooth count high, and if you want to get sprockets made it may help to know that they can also be pretty cheaply cut out from 4mm sheet by waterjet, let me know if you want details, or a dxf file.
 
sn0wchyld said:
Hey mate - are you able to share the method for making a 219# sprocket profile? Ive got a few different sizes im looking to cut, any help appreciated cheers mate.

I have my sprockets laser cut. So I create cutting paths in a vector art program (Adobe Illustrator). Here is my process:

Calculate the sprocket pitch diameter by multiplying the chain pitch (.3061" or 7.775mm for #219) by the number of teeth you want on the sprocket. This gives you the sprocket pitch circumference. Divide by pi (3.1416 is precise enough) for the sprocket pitch diameter. Create a circle this diameter. I then divide 360 degrees by the number of teeth. This is the amount that you rotate your sprocket outline for each tooth that you place on the pitch diameter. The pitch diameter runs right through the centerline of the link pins. I used a pin diameter of .1795". I'm attaching my drawing for a 40T #219 sprocket.

40t_219_template.jpg


It would be a lot easier to punch the parameters into an engineering program. I don't like the price tag on most of those apps. I've gotten fast enough at doing it the hard way for my purposes. I hope this helps.

-Mike
 
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