REVIEW: QR-E 250W ELECTRIC BOOSTER BICYCLE MOTOR AND B60i AND B70 BATTERY

What made you decide on the Flex vs the Pro? Is the lower wattage an advantage or a disadvantage? Did you order directly or through eBay? It says on their website 7 to 10 business days via FedEx. Is that inaccurate
Decided on the Flex after much deliberating and not wanting single purpose/proprietary batteries. My world revolves around small, light, efficient, versitility and minimal gear to store. My goal was to use the 2 Full battery packs that EMGX pictured a few post back. These power my Shimano mid drive as range extenders and power a newly built 18lb electric boat, so wanted to stay with compatibility.

I ordered off the website $218 shipped, was supposed to be 12 day delivery, however, mine ordered on oct 15 wont get here till Dec 3-5th. I've never even seen one of these in operation and have kind of struggled to grasp how it will all work. Used to be excited thinking the electric clutch would seperate from the tire giving me a true freeroll but have since found out differently. Not enthused about getting off the bike before and after a hill to engage or disengage. Reading the post from you guys has helped a lot. Trying to communicate with Jason by email in different time zones, communication gaps up to a few days etc is a long drawn out experience when you have many questions.
 
I wouldn't recommend voltage regulator unless you know the peak amp (A) current consumption required between the battery and drive unit. Else i would love to use back my 52V 17Ah bafang battery pack on my Qiroll unit. You'll need to contact with Qiroll support, they have engineers on how to make thing works with battery compatibility.
I've already discussed with Jason, a 36v battery either won't work or could cause harm.
 
I've already discussed with Jason, a 36v battery either won't work or could cause harm.
Seems these are proprietary voltages and communication with the unit. I'm used to this as all the new major brand mid drives seem to require their own batteries
 
Decided on the Flex after much deliberating and not wanting single purpose/proprietary batteries. My world revolves around small, light, efficient, versitility and minimal gear to store. My goal was to use the 2 Full battery packs that EMGX pictured a few post back. These power my Shimano mid drive as range extenders and power a newly built 18lb electric boat, so wanted to stay with compatibility.

I ordered off the website $218 shipped, was supposed to be 12 day delivery, however, mine ordered on oct 15 wont get here till Dec 3-5th. I've never even seen one of these in operation and have kind of struggled to grasp how it will all work. Used to be excited thinking the electric clutch would seperate from the tire giving me a true freeroll but have since found out differently. Not enthused about getting off the bike before and after a hill to engage or disengage. Reading the post from you guys has helped a lot. Trying to communicate with Jason by email in different time zones, communication gaps up to a few days etc is a long drawn out experience when you have many questions.
That sucks on the delivery delay. I wonder why. I appreciate your honest perspective and second thoughts. It appears the clutch system works differently than expected, giving me pause. The pro's power is appealing, but the proprietary battery makes me doubt using it as a DIY person.

My alternative is to get a combo like this for my hybrid: Toseven DM02 500w Mid Drive Motor and 36V 12.8ah - ECO PACK - USED TESTED
 
Seems these are proprietary voltages and communication with the unit. I'm used to this as all the new major brand mid drives seem to require their own batteries
The mid-drive I'm looking at should work with any 36/48 batteries. See my other reply.
 
Interesting that Shimano Steps will work on batteries without data ports to communicate with the Shimano controller. Is this the battery? Light and small.
View attachment 184996

You do have to stop to disengage the Qiroll from the wheel. It keeps running in the "electronic clutch" mode until you've slowed down to near stop - then you use the thumb screw to back the motor off of the wheel. Due to the electronic clutch there is some assist even if you don't actuate the motor as it kicks in as soon as you get above a few mph as long as the battery is plugged in. If you don't mind post pictures of the bike you are intending to use it on, 17# is impressive for a non-carbon bike.
This is the battery. Light, small, efficient and good quality....these are my go too's unless I find something better
 
The mid-drive I'm looking at should work with any 36/48 batteries. See my other reply.
I've never tried one of these mid drives. The one I have works great but it's a 45lb bike. What I'm trying to accomplish is a lighter bike and most importantly a good freewheel experience, something all other systems lack. I think the amazon friction drive you found has promise as it would electronically engage but there is a ton of unknowns with that.
This is the battery. Light, small, efficient and good quality....these are my go too's unless I find something better
The mid-drive I'm looking at should work with any 36/48 batteries. See my other reply.
 
I've never tried one of these mid drives. The one I have works great but it's a 45lb bike. What I'm trying to accomplish is a lighter bike and most importantly a good freewheel experience, something all other systems lack. I think the amazon friction drive you found has promise as it would electronically engage but there is a ton of unknowns with that.
Yeah, the appeal of friction drive is that it can be wholly disengaged and is lightweight, but based on what you're saying, I'm unsure about this method.
 
Yeah, the appeal of friction drive is that it can be wholly disengaged and is lightweight, but based on what you're saying, I'm unsure about this method.
The last 10-15yrs I've been searching for a way to electrify my light, versitle xc bike made. I can't put heavy parts like hub or mid drives on her after replacing just about everything to reduce weight. The QR is my only attempt and seemingly viable option in the marketplace. Based on 3dxl and emgx's experience with hills, I'm not very optimistic, especially knowing 3d's already has a light road bike and in great physical biking shape. I was kinda banking on a 21 lb bike including electrics to make up for lower power. Not sure it will work but will give it a try.

About 30 years ago I met a couple of biking electrical engineers who let me use their friction drive product designed to give a boost over tough hills. It was a water bottle battery with a very quick to mount, small friction drive. The thing I remember was it engaged to the tire electronically which made it very convenient and practical. The range wasn't good, I was in great shape at the time so lost interest but think they nailed it with the electric engagement to the tire. Kinda think this is what will make a viable friction drive pop looking forward.
 
Used to be excited thinking the electric clutch would seperate from the tire giving me a true freeroll but have since found out differently. Not enthused about getting off the bike before and after a hill to engage or disengage.

Just my opinion but I wouldn't worry much about physically disengaging the drive unit unless you ride in mud or other debris that you don't want to wedge between the tire and the roller (I addressed that somewhat by mounting the unit on a spring base so it can be pushed away from the tire instead of the drive being fixed and immobile). The "electronic clutch" uses very little battery and except for a small amount of assist that it provides it isn't really noticeable to me when riding. I entirely agree about bike weight being an issue for me. If the Qiroll Mute Plus had worked better for me where I wanted assist on steeper grades I would have considered buying a very light weight bike, possibly carbon fiber, to use it on. I hope it works well for what you want, time and your experience will tell.
The more powerful, standard 48v, disengaging drive unit that meta linked on Amazon is interesting but not enough info to purchase with confidence, for me at least.
 
The last 10-15yrs I've been searching for a way to electrify my light, versitle xc bike made. I can't put heavy parts like hub or mid drives on her after replacing just about everything to reduce weight. The QR is my only attempt and seemingly viable option in the marketplace. Based on 3dxl and emgx's experience with hills, I'm not very optimistic, especially knowing 3d's already has a light road bike and in great physical biking shape. I was kinda banking on a 21 lb bike including electrics to make up for lower power. Not sure it will work but will give it a try.

About 30 years ago I met a couple of biking electrical engineers who let me use their friction drive product designed to give a boost over tough hills. It was a water bottle battery with a very quick to mount, small friction drive. The thing I remember was it engaged to the tire electronically which made it very convenient and practical. The range wasn't good, I was in great shape at the time so lost interest but think they nailed it with the electric engagement to the tire. Kinda think this is what will make a viable friction drive pop looking forward.

I've been researching alternatives on the Endless Sphere forums, here, and eBikes Discord. Everything has its pros and cons. Mid-drives have a lot of power and can handle almost any terrain or condition, but they seem to break frequently, wear down the drivetrain a lot, and are often unreliable. The QiRoll, based on 3dxl's comments, is at least very reliable. Although the 3M grip tape hack should probably be used for hills and wet conditions, that's a minor tweak compared to the epic MacGyvering I'm reading about with mid-drives. Bafangs seem to be a more reliable mid-drive brand, but cadence riding kind of sucks, IMO — it feels more like a moped than a bike.

This thread alone makes me hesitant about mid-drive solutions.

I've had front and rear hub drives in the past, but after about a year, the internal gearing overheats because of constant hill climbs. I had one Direct Drive, but that was a burden because it wasn't consistent unless I gave it constant power, anything less, and it resisted my pedaling.

For me, what's promising is 3dxl's experiences with QiRoll. So far, he's been running them on two bicycles in somewhat rigorous traffic and brutal road conditions.

The fact that it can be physically disengaged, even if it requires stopping and doing that, is a huge plus. That means I can use the bike normally whenever I want, and it's not a permanent ebike mod — a major plus because I also use my bike to keep in shape.

The other factor is weight. Mid-drives and hubs are heavy, and so are batteries. Often so heavy, I wonder how much of the ebike wattage is being used to carry the motor/battery/controller vs my own pedaling.

Jason, I assume the owner of Qiroll, has been fantastic with replying to my questions.

By the way. He said the Flex is bidirectional, but for engineering/safety measures, they couldn't make it have regen with third-party batteries. I'll quote what he said; I'm sure he won't mind:

"Flex has bidirectional function but no regenerative braking because many third-party electrical structures are not optimized for regeneration and for safety reasons, this function is not available."

The more I research and discover problems with other methods, the more likely I'll get the QiRoll Pro.
 
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That sucks on the delivery delay. I wonder why. I appreciate your honest perspective and second thoughts. It appears the clutch system works differently than expected, giving me pause. The pro's power is appealing, but the proprietary battery makes me doubt using it as a DIY person.

My alternative is to get a combo like this for my hybrid: Toseven DM02 500w Mid Drive Motor and 36V 12.8ah - ECO PACK - USED TESTED
Mind you this is for the Flex

Sorry Don
Flex motors have been delayed in factory delivery due to the current production capacity limitations of the new model. We have also been communicating about the performance of the motors before to avoid the product not meeting your expectations, which will be a loss for both of us. At present, your motor is in transit. In order to make up for the previous delay in delivery speed, I have arranged DHL air transportation, and the time for the goods to arrive in the United States is consistent with the early December indicated in the previous email.
49 days is the rule restriction date of some e-commerce platforms, not our delivery date, please don't worry.
Thank you for your understanding and support.
Best Regard
Jason
 
Just my opinion but I wouldn't worry much about physically disengaging the drive unit unless you ride in mud or other debris that you don't want to wedge between the tire and the roller (I addressed that somewhat by mounting the unit on a spring base so it can be pushed away from the tire instead of the drive being fixed and immobile). The "electronic clutch" uses very little battery and except for a small amount of assist that it provides it isn't really noticeable to me when riding. I entirely agree about bike weight being an issue for me. If the Qiroll Mute Plus had worked better for me where I wanted assist on steeper grades I would have considered buying a very light weight bike, possibly carbon fiber, to use it on. I hope it works well for what you want, time and your experience will tell.
The more powerful, standard 48v, disengaging drive unit that meta linked on Amazon is interesting but not enough info to purchase with confidence, for me at least.
Agreed. Jason from QiRoll has been responding to my emails. Flex is bidirectional, FYI. But I'll probably go for the Pro version since it's more powerful and purchase an extra battery for it, eventually, when I order. There is a two-battery version.

However, Jason said: "What is the riding distance? Generally, a set of H70 batteries can fully meet the needs of a day's riding. We recommend that you try to order a set of H70 first, and then decide whether to continue to purchase batteries after using them for a period of time." and "If you have an existing 36V battery, we recommend ordering a Flex to give it a try. If it works as you expect, then ordering a more comprehensive PRO is a solid choice."

So he provides pretty sincere and reasonable non-sales pitchy advice. That earns high respect from me.

In my case, I'd consider ordering two quick-releases and an extra Qiroll S2 start switch + Power cable. That would make it easy to swap between my bicycles.

If I order so much, all at once, I'll see if they offer a discount.

I also asked him about S-1 vs S-2 switches, and he said: "The latest batch has all been updated to S-2 switches, which are an upgraded version of S-1, smaller and less prone to damage."
 
Mind you this is for the Flex

That's great!

Jason's honest communication and follow-up support are really making me want to order this. I consider that an important factor when purchasing a product, especially for this kind of project.
 
Can a voltage regulator be used to connect the Pro to standard 36V batteries?

Like these ones.
1730221149547.png

I'm not saying it'd work, but maybe a step down to actual 36v could possibly work with the 33v Pro. You'd have to check but I think a prior post several pages back indicated that 38v didn't work but maybe 36v is close enough? Personally I don't think that I'd risk it but I did use a similar 36/48v to 24v step down Buck converter on my Mute version and it worked without an issue. The converter didn't get hot with miles of continuous use and it seemed peppier than the Qiroll battery which starts at 25v then drops with use while the Buck converter maintained 24v output continuously as close to the battery's low voltage cut out as I ran it.
 
View attachment 185014

I'm not saying it'd work, but maybe a step down to actual 36v could possibly work with the 33v Pro. You'd have to check but I think a prior post several pages back indicated that 38v didn't work but maybe 36v is close enough? Personally I don't think that I'd risk it but I did use a similar 36/48v to 24v step down Buck converter on my Mute version and it worked without an issue. The converter didn't get hot with miles of continuous use and it seemed peppier than the Qiroll battery which starts at 25v then drops with use while the Buck converter maintained 24v output continuously as close to the battery's low voltage cut out as I ran it.
Good information, worth noting.

If a QR Pro battery dies, I suppose simply take it apart, find out what kind of cells it uses and BMS, and clone them. Easier said than done, I'm sure. But there are a bunch of battery repair people who might be up to the task. That's assuming the company no longer exists at that time.
 
Good information, worth noting.

If a QR Pro battery dies, I suppose simply take it apart, find out what kind of cells it uses and BMS, and clone them. Easier said than done, I'm sure. But there are a bunch of battery repair people who might be up to the task. That's assuming the company no longer exists at that time.
Jason didn't think any other battery would work because they were designed to communicate with the power unit. He said it might but also may kill the power unit as well. Think the whole regen electronics hinder but I would be willing to live without this if needed. Regen has never been that effective in any EV I've ever looked into. Wish it was a straight 36v, then I could use his batteries for my other electric project like my boat and mid drive ebike
 
Jason didn't think any other battery would work because they were designed to communicate with the power unit. He said it might but also may kill the power unit as well. Think the whole regen electronics hinder but I would be willing to live without this if needed. Regen has never been that effective in any EV I've ever looked into. Wish it was a straight 36v, then I could use his batteries for my other electric project like my boat and mid drive ebike
For e-bikes, what I've seen mentioned as the most helpful part of regen is that it helps with braking to save on rim/disc brake pad wear and tear. I'm not sure how that works with the QiRoll — perhaps it creates a magnetic rolling resistance to avoid too much friction on the tire.
 
I've been researching alternatives on the Endless Sphere forums, here, and eBikes Discord. Everything has its pros and cons. Mid-drives have a lot of power and can handle almost any terrain or condition, but they seem to break frequently, wear down the drivetrain a lot, and are often unreliable. The QiRoll, based on 3dxl's comments, is at least very reliable. Although the 3M grip tape hack should probably be used for hills and wet conditions, that's a minor tweak compared to the epic MacGyvering I'm reading about with mid-drives. Bafangs seem to be a more reliable mid-drive brand, but cadence riding kind of sucks, IMO — it feels more like a moped than a bike.

This thread alone makes me hesitant about mid-drive solutions.

I've had front and rear hub drives in the past, but after about a year, the internal gearing overheats because of constant hill climbs. I had one Direct Drive, but that was a burden because it wasn't consistent unless I gave it constant power, anything less, and it resisted my pedaling.

For me, what's promising is 3dxl's experiences with QiRoll. So far, he's been running them on two bicycles in somewhat rigorous traffic and brutal road conditions.

The fact that it can be physically disengaged, even if it requires stopping and doing that, is a huge plus. That means I can use the bike normally whenever I want, and it's not a permanent ebike mod — a major plus because I also use my bike to keep in shape.

The other factor is weight. Mid-drives and hubs are heavy, and so are batteries. Often so heavy, I wonder how much of the ebike wattage is being used to carry the motor/battery/controller vs my own pedaling.

Jason, I assume the owner of Qiroll, has been fantastic with replying to my questions.

By the way. He said the Flex is bidirectional, but for engineering/safety measures, they couldn't make it have regen with third-party batteries. I'll quote what he said; I'm sure he won't mind:

"Flex has bidirectional function but no regenerative braking because many third-party electrical structures are not optimized for regeneration and for safety reasons, this function is not available."

The more I research and discover problems with other methods, the more likely I'll get the QiRoll Pro.

  1. Qiroll Pro: 3M floor grip tape is a must do mods if you wanted to experience 1:1 power transfer ratio full torque transfer to the wheels even when not use for hill climbing or riding on wet road. On stock default supplied friction tape; when riding on flat road i can feel it slipped losses 40% power transfer to wheel along the way. 3M floor grip tape felt like i punched in a nitro boost...its a day and night experience.
  2. Mid drive and hub drive are great unit to experience real ebike 'power' but need more money and maintenance down time to keep up with the wear and tear parts replacement for daily use. Probability of breakdown is higher per-year based on my experience with mid drive MTB and road bike for daily commute. In my case: parts replacement such as chain, chainring and cassette have to change twice a year because of the torque load it pull. If it breaks down, you'll be dragging a stonehedge weight of an ebike, almost impossible to pedal back home. It takes lots of power/wattage to use scooter mode on mid drive (almost 3x wattage comparison to friction drive) which causes battery to sag voltage at acceleration startup and reduce battery lifespan because it has to haul a heavy mid drive bicycle. My mid drive battery worn out faster and cost me arm and legs for a new pack plus its heavy...lasts me a year per-pack.
  3. Go Qiroll Pro + H70 pack, it have 'almost' same scooting power as 750w mid drive Bafang without killing your battery from over wattage consumption.
  4. My Qiroll H70 battery pack still living well and healthy since i joined this forum years ago, Bafang mid drive battery pack however changed twice and still showing voltage sag/deterioration.
  5. Summary experience on Mid drive (Bafang) within 2 years: Handles like heavy dump truck...watchout when cornering and braking but wins the hill. I stranded on the road twice due to motor jammed (lost working days), money pit replacing chain, casette, chain rings and over priced battery, water damage to battery and li-on cell corrosion, worn out clutch shaft and b-level gear, Bottom bracket bearing worn out. All this replacement happened in a (1) year. My car annual maintenance is cheaper than this!
  6. Summary experience on Qiroll Pro within 2 years: Handles like normal bike=nimble (lighter) but have to pedal up the hill a bit. Just the roller bearing starting to make 'jet like engine sound' (as shown in previous twitter video) after 1.5 year....maybe a cool factor but it won't affect the ride quality. Bike component worn out like normal bicycle life span, changed drive parts every 2 years including tires. Takes 1~3 minutes to replace wornout 0.50 cent 3M grip tape every 2 months if seen needed. Never fail to cycle back home or to work = 100% success commute without problem even if there is a problem but will not be a problem. Public still think i'm riding a normal looking bicycle but with extra speed and low effort. :)
  7. Candence makes me insomnia. Scooting and 'ghost' pedalling make me sleep better at night...hehehe. (Btw mid 40s guy right here.)
 
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  1. Qiroll Pro: 3M floor grip tape is a must do mods if you wanted to experience 1:1 power transfer ratio full torque transfer to the wheels even when not use for hill climbing or riding on wet road. On stock default supplied friction tape; when riding on flat road i can feel it slipped losses 40% power transfer to wheel along the way. 3M floor grip tape felt like i punched in a nitro boost...its a day and night experience.
  2. Mid drive and hub drive are great unit to experience real ebike 'power' but need more money and maintenance down time to keep up with the wear and tear parts replacement for daily use. Probability of breakdown is higher per-year based on my experience with mid drive MTB and road bike for daily commute. In my case: parts replacement such as chain, chainring and cassette have to change twice a year because of the torque load it pull. If it breaks down, you'll be dragging a stonehedge weight of an ebike, almost impossible to pedal back home. It takes lots of power/wattage to use scooter mode on mid drive (almost 3x wattage comparison to friction drive) which causes battery to sag voltage at acceleration startup and reduce battery lifespan because it has to haul a heavy mid drive bicycle. My mid drive battery worn out faster and cost me arm and legs for a new pack plus its heavy...lasts me a year per-pack.
  3. Go Qiroll Pro + H70 pack, it have 'almost' same scooting power as 750w mid drive Bafang without killing your battery from over wattage consumption.
  4. My Qiroll H70 battery pack still living well and healthy since i joined this forum years ago, Bafang mid drive battery pack however changed twice and still showing voltage sag/deterioration.
  5. Summary experience on Mid drive (Bafang) within 2 years: Handles like heavy dump truck...watchout when cornering and braking but wins the hill. I stranded on the road twice due to motor jammed (lost working days), money pit replacing chain, casette, chain rings and over priced battery, water damage to battery and li-on cell corrosion, worn out clutch shaft and b-level gear, Bottom bracket bearing worn out. All this replacement happened in a (1) year. My car annual maintenance is cheaper than this!
  6. Summary experience on Qiroll Pro within 2 years: Handles like normal bike=nimble (lighter) but have to pedal up the hill a bit. Just the roller bearing starting to make 'jet like engine sound' (as shown in previous twitter video) after 1.5 year....maybe a cool factor but it won't affect the ride quality. Bike component worn out like normal bicycle life span, changed drive parts every 2 years including tires. Takes 1~3 minutes to replace wornout 0.50 cent 3M grip tape every 2 months if seen needed. Never fail to cycle back home or to work = 100% success commute without problem even if there is a problem but will not be a problem. Public still think i'm riding a normal looking bicycle but with extra speed and low effort. :)
  7. Candence makes me insomnia. Scooting and 'ghost' pedalling make me sleep better at night...hehehe.
You may want to convince Jason to offer the 3M Grip Tape or something similar for their product. It sounds like a game-changer and alters the ability of the Qiroll to do what it's meant to do.
 
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