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

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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.
 
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.
I think you should get 3M floor grip tape from local hardware store better, you can test several type of surface rough abrasion that suits your tire and cheaper per-roll tape. Here i can get it around $1~3 per-roll which can last me 1 to 2 year of use. Like this one: https://www.3m.com/3M/en_US/p/c/tapes/anti-slip-grip/
 
Yes! That's it! Go get one.

When you get your Qiroll try the original friction tape first and ride everywhere including pedalling up the hill before install the 3M to experience the ride differences between each type of tape so you can appreciate the differences. ;)

*Ps: Wow $13! Mines just under $3. Btw both still worth it.
 
I think you should get 3M floor grip tape from local hardware store better, you can test several type of surface rough abrasion that suits your tire and cheaper per-roll tape. Here i can get it around $1~3 per-roll which can last me 1 to 2 year of use. Like this one: https://www.3m.com/3M/en_US/p/c/tapes/anti-slip-grip/
I'm also considering whether to get the Pro, which is $439, or the Flex for $198 with these batteries for $147.

I realize the Pro has slightly more power, but using any 36-volt battery is very tempting. I could expand the range at minimal cost.

Jason mentioned I should consider the Flex if I have the 36-volts available. He must not consider the wattage difference that important.
 
Yes! That's it! Go get one.

When you get your Qiroll try the original friction tape first and ride everywhere including pedalling up the hill before install the 3M to experience the ride differences between each type of tape so you can appreciate the differences. ;)

*Ps: Wow $13! Mines just under $3. Btw both still worth it.
It's probably because of Amazon Prime. I will check around the local hardware stores as well. But Prime is just very convenient.
 
I'm also considering whether to get the Pro, which is $439, or the Flex for $198 with these batteries for $147.

I realize the Pro has slightly more power, but using any 36-volt battery is very tempting. I could expand the range at minimal cost.

Jason mentioned I should consider the Flex if I have the 36-volts available. He must not consider the wattage difference that important.

Better get the PRO version with H70 battery pack if you wanted to experience actual ebike performance. Its kind of dangerous to use external/non-compatible battery mated with PRO because if the QIROLL PRO unit does an accidental re-gen activation the battery will get hit by unwanted 'recharge back' and might get damaged. Some battery does not perform well when discharged to power the drive unit and recharge back at the same time (Depends on internal BMS board). Even if you use voltage regulator to step down the battery voltage the re-gen feature will unintentionally going to destroy the voltage regulator. That's based my experience building lithium/li-on battery packs for my RC models. "Its better pay once than paying twice for mistake."
 
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Better get the PRO version with H70 battery pack if you wanted to experience actual ebike performance. Its kind of dangerous to use external/non-compatible battery mated with PRO because if the QIROLL PRO unit does an accidental re-gen activation the battery will get hit by unwanted 'recharge back' and might get damaged. Some battery does not perform well when discharged to power the drive unit and recharge back at the same time (Depends on internal BMS board). Even if you use voltage regulator to step down the battery voltage the re-gen feature will unintentionally going to destroy regulator. That's based my experience building lithium/li-on battery packs for my RC models. "Its better pay once than paying twice for mistake."
Yeah, the Pro seems a bit faster. But have you seen the Flex? It's specifically designed to accept 36-volt batteries.

Here it is: https://qirollshop.com/product/qr-e-flex-motor/

But yeah, the drawback is the Flex is only 240W, whereas the Pro is 320W.

I imagine the Pro's 80 extra watts would make a significant difference for climbing hills. So I'm probably going to get the Pro as you advise.

It's unfortunate, they don't make a 320W Flex. That would be an ideal combination.
 
Yes i've seen the Flex but due to my nature doing daily commute and brushing with road traffic i need 320W for safety reason and getting good sleep after few hill climbs. I don't want muscle pain and get chased by dogs. ;)
 
Yes i've seen the Flex but due to my nature doing daily commute and brushing with road traffic i need 320W for safety reason and getting good sleep after few hill climbs. I don't want muscle pain and get chased by dogs. ;)
I've seen your videos. Quite incredible! Do you have any of yourself using the Pro and going up hills? Just wondering how that is.
 
I've seen your videos. Quite incredible! Do you have any of yourself using the Pro and going up hills? Just wondering how that is.
I can't recall if i posted that hill climb video on twitter, however its always keep on pedaling 40% effort with the throttle button keep pressed on giving me a crawl speed of 10~15km/h up the 20% gradient slope reaching around 80 meter elevation.
 
I can't recall if i posted that hill climb video on twitter, however its always keep on pedaling 40% effort with the throttle button keep pressed on giving me a crawl speed of 10~15km/h up the 20% gradient slope reaching around 80 meter elevation.
Seeking your wisdom.

My plan would be to get a QiRoll Pro, two quick-release adapters, and a second Qiroll S2 start switch + Power cable. I would swap the Qiroll Pro and a battery between my bicycles and get a second QiRoll Pro later, so I'd have two batteries.

What do you think of that?

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Yes! That's it! Go get one.

When you get your Qiroll try the original friction tape first and ride everywhere including pedalling up the hill before install the 3M to experience the ride differences between each type of tape so you can appreciate the differences. ;)

*Ps: Wow $13! Mines just under $3. Btw both still worth it.
I see an option for 1", 2", and 4" width grip tape. Which size should I get? I'll order it before I get the Qiroll Pro. Thanks!
 
Seeking your wisdom.

My plan would be to get a QiRoll Pro, two quick-release adapters, and a second Qiroll S2 start switch + Power cable. I would swap the Qiroll Pro and a battery between my bicycles and get a second QiRoll Pro later, so I'd have two batteries.

What do you think of that?

Should be no problem with quick release adapter if you wanted to be frugal with one unit of Pro swapping about.
Btw i love your folding bike, that's the one i'm planing to get for next Qiroll Pro project. I'm aim for Fnhon Gust brand model like yours, looks identical. Is that a 16" wheel?

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I see an option for 1", 2", and 4" width grip tape. Which size should I get? I'll order it before I get the Qiroll Pro. Thanks!

My grip tape width is 25mm, fits exactly on Qiroll Pro roller groove.

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Should be no problem with quick release adapter if you wanted to be frugal with one unit of Pro swapping about.
Btw i love your folding bike, that's the one i'm planing to get for next Qiroll Pro project. I'm aim for Fnhon Gust brand model like yours, looks identical. Is that a 16" wheel?

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My grip tape width is 25mm, fits exactly on Qiroll Pro roller groove.

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Thanks for the measurement info!

Yes, 16" wheel. This is the bicycle. I modified the drive train with 52T NW Chainring, Microshift Advent SuperShort RD with clutch, 11-38 cassette, and Microsoft thumber shifters (in friction mode.) My 700c hybrid has 30T NW chainring and the same Microshift components. They have nearly identical gear-ratios for a common riding feel, and I can stock up on the same cassettes for both.

I watched your installation video, so the QR swap method might not work if the Qiroll Pro has to be adjusted each time per bicycle. Would that be the case?
 
How fast can you ride with 16" with that gear ratio. I have similar gear ratio with Shimano Tiagra group set ready for my folding project. (have problem with dogs around the neighborhood). I can't wait to see how you install Qiroll Pro on this frame.

Btw yes Qiroll Pro need to be adjusted per-bike. Sometime takes time to find the 'sweet spot' during adjustment where i get right amount of grip contact and rolling resistance pressure during mechanical clutch adjustment. This why i prefer permanent installation than swapping about to avoid hassle especially if both bike are used frequently/daily.
 
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