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

Do you think the Pro would've made a big difference for you?

33% higher rated power sounded nice but not necessarily game-changing to me - I was also interested in the regenerative braking. Brake overheating is a hazard for tandem bikes - with double the weight on the same two wheels and rim (or disc brakes, I gather) brakes - on long/steep enough hills. Heck, just slowing sufficiently with only the canti brakes can be dicey on a downhill in the rain.

And actually my ancient (25 years?) tandem already has a front-wheel drum brake to assist with downhill braking. But that comes with a few compromises, and I feel like the regen braking could perform a similar function if I want to swap out the drum brake for a simpler, lighter hub.
As a guy who ride fast daily and brakes a lot on Qiroll Pro down the hill don't put 100% trust on regen braking to slow you down completely especially on heavy bikes. Pros: Its slow down "linearly" and recharge back the battery pack. Cons: It doesn't slow down heavy bikes above 20kg especially going downhill and won't be efficient on wet road with stock friction tape. You'll still need physical brake lever to slow down the bike down even with regen braking activated.
 
I just went for E-Switchy conversion kit.. seems to be the easiest installation out there. The 3lb Battery looks like a water bottle and that 250W is pretty quick.. Plus i like the sleek and clean design, only one cable to connect and off we go!

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I just went for E-Switchy conversion kit.. seems to be the easiest installation out there. The 3lb Battery looks like a water bottle and that 250W is pretty quick.. Plus i like the sleek and clean design, only one cable to connect and off we go!
Looks very minimalist, i like it. Stealthy front motor hubs looks like classic drum brake. Is that led strips around the wheel spokes?
 
Looks very minimalist, i like it. Stealthy front motor hubs looks like classic drum brake. Is that led strips around the wheel spokes?
Thank you! Yes! it's an LED light looks pretty cool at night, will try adding some pics but overall very happy with the E-Switchy kit
 
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Just got the qiroll recently and have been riding more often and further than ever. It's barely even noticeable when installed near the chains.

Stock friction tape sucks and only lasts around 10km before falling off. Tried the floor grip tape which lasts maybe 50km for me. Currently trying out sandpaper belt for belt sanders which seems to be the best option so far. Also started to design a better TPU tape to 3d print.
 
Just got the qiroll recently and have been riding more often and further than ever. It's barely even noticeable when installed near the chains.

Stock friction tape sucks and only lasts around 10km before falling off. Tried the floor grip tape which lasts maybe 50km for me. Currently trying out sandpaper belt for belt sanders which seems to be the best option so far. Also started to design a better TPU tape to 3d print.
Nice stealth setup, barely looks like an ebike. Keeping things looks like normal commuter bike.
 
Anyone have experience with installing qiroll on a Brompton? I know there's an installation on their website (https://qirollshop.com/install/) that says it's compatible, but it looks like installing in the rear triangle will interfere with the seat post from engaging the seat post stop in the folded position.
 
Has anyone installed this kit on a bike with a carbon frame?
I have a Giant Defy road bike, with a carbon frame, and I'm looking for a DIY kit to give me a boost on the hills.

Is the roller pressed against the tire 100% of the time? If so, I'm wondering how much of a drag it creates, when riding with the power off (or does the power have to be on all the time?)
 
There are pictures of carbon bikes with Qiroll installed including one somewhere in this thread. Some people have used what looks like a putty substance between the attachment plates and the carbon tubes, I assume for protection - I'd be cautious to avoid crush damage. The roller can be easily mechanically retracted from the tire with its screw knob. With power entirely off (battery disconnected) and motor on the tire there is some drag but if the battery is connected there is an "electronic clutch", as they call it. As long as there is power to the unit it spins the motor negating any drag and providing a small amount of assist if the wheel is turning beyond a couple MPH. There are only two levels of assist (other than the "electronic clutch) activated and toggled between them with buttons on the control. There are significant limitations: you have to press a button continuously for assist (besides the "electronic clutch" default), The friction layer is notorious for slipping on anything other than a smooth tire tread and on a wet tire, the stock friction layer is also prone to early failure. I have the "Mute Plus" version, it provides assist on flats and more gentle hills but not when I really want it - caveat is that I live where the hills are long and steep, up to 20+%. I have no experience with the Pro version but 3dxl reports indicate it to be much more powerful and helpful on hills. I don't see a lot of other complaints about lack of assist on hills so maybe it's just me.

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I gave the Qiroll Mute Plus another test run yesterday on a 19+ mile ride that doesn't have steep grades - total 600 feet elevation gain per Google Maps. The battery wasn't fully charged at the start but all 4 indicator lights were lit, at the end of ride one was lit and another flickering. I used boost generously except when the power cable detached from the drive unit which was frequently when on rough pavement. I didn't notice slipping using sanding belt as the friction layer along with a spring hinge adjusted to maximum torsion, Continental Double Fighter tires with Tannus inserts. I'm going to silicone glue a short power extension cord on the motor (along with a short USB micro data extension) to prevent them from pulling out of the drive unit. I don't want the full length cables glued.

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Has anyone installed this kit on a bike with a carbon frame?
I have a Giant Defy road bike, with a carbon frame, and I'm looking for a DIY kit to give me a boost on the hills.

Is the roller pressed against the tire 100% of the time? If so, I'm wondering how much of a drag it creates, when riding with the power off (or does the power have to be on all the time?)
On my bike setup 100% of the time pressed against the tire. When power off = lots of drag (depends how tight you push the clutch roller to the tire). I run with power on all the time for commute to work.
 
Anyone have experience with installing qiroll on a Brompton? I know there's an installation on their website (https://qirollshop.com/install/) that says it's compatible, but it looks like installing in the rear triangle will interfere with the seat post from engaging the seat post stop in the folded position.
Planning to get brompton (cheapo clone) and fit with qiroll soon. Wait until i get the budget and post my setup here.
 
Any update on the more powerful Qiroll prototype that you are testing 3dxl?
No updates, i don't see any releases on the powerful Qiroll on their website either. After i send feedback about the prototype unit being not able to fit on normal size "performance" bike they seems to immediately getting back into the drawing board trying to make adjustment to the clutch limit reach issues....its way to big to fit to touch the tires. It needs longer rear bike triangle frame/chain stay to fit in between it. I try to fit on common bikes ranging from mtb frame 26" wheel up to 29" ~700c none able to fit in. I was wondering how they they able to release a prototype without even test it on performance bicycles. I suspect its was build and tested on some folding bike or "cruiser" with longer rear triangle stays. Else maybe i'll used it on push scooter if it still doesn't fit on a bike, lol.
 
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I found the stock Qiroll two button actuator difficult to use while wearing gloves, the old version with a toggle along with a mode button would have been better for me but unfortunately discontinued.
A while ago I made an actuator switch with these momentary push buttons.

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It worked well but the buttons aren't robust enough for this application and one jammed and broke after minimal usel
So I substituted these momentary blade switches, hoping they hold up better. I'm experimenting a bit with locations that suit me best. Inexpensive and easy to make if you can solder fine wires.
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If anyone has a better solution please post your idea(s).
 
I found the stock Qiroll two button actuator difficult to use while wearing gloves, the old version with a toggle along with a mode button would have been better for me but unfortunately discontinued.
A while ago I made an actuator switch with these momentary push buttons.

View attachment 191871
It worked well but the buttons aren't robust enough for this application and one jammed and broke after minimal usel
So I substituted these momentary blade switches, hoping they hold up better. I'm experimenting a bit with locations that suit me best. Inexpensive and easy to make if you can solder fine wires.
View attachment 191870

If anyone has a better solution please post your idea(s).
Yes the old version "trigger" switch was comfortable and easy on my cycling glove too. However after a year expose to heat weather and sunlight the plastic case breaks spilling all those switch parts guts out. The button type is robust/durable but hard to press and hold constantly throughout the ride. Wish they re-introduce back soft trigger switch than button.
 
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