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

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.
If I recall, with the 16" folder I've gotten to 20 to 25+ (MPH) on a reasonable flat. It can accelerate a lot faster than my 700c. I can go up hills fairly well with it, too. I mainly want the Qiroll Pro for energy breaks on long rides, acceleration from stops, and hopefully a little boost up hills (with the grip tape.)

Looks like the QR swap method is not a great idea. I'll just get a second Pro at some point. I suppose they mainly offer a QR attachment to prevent theft.
 
Got notice my flex will be delivered. Is the roller size the same as the Pro? This is the tape 3XL recomended off a previous post. Is the one to get or should I look elsewhere here in San Diego like a home depot? At $25, looks like I'm a little higher here.


Also, has anyone changed, modified their switch so you don't have to hold it down to active it? Thinking a cut off with my brake type of mod.
 
Got notice my flex will be delivered. Is the roller size the same as the Pro? This is the tape 3XL recomended off a previous post. Is the one to get or should I look elsewhere here in San Diego like a home depot? At $25, looks like I'm a little higher here.


Also, has anyone changed, modified their switch so you don't have to hold it down to active it? Thinking a cut off with my brake type of mod.
https://www.amazon.com/dp/B0006HVKLK/ — this one is $13.38.
 
I hope that the friction tape works well for you and you post up your experiences one way or the other. I've mentioned before that it didn't work for me. I started with a generic product, then 3M Safety Walk and finally Gorilla brand. The grit on all three quickly wore off exposing the underlying tape with slippage. From what I gather from 3dxl's posts he presses the roller very hard on the tire while I followed the Qiroll instructions regarding pressure of the roller on the tire so that might have been the difference. If you check the GBoost product page for their friction drive you can see what they use instead, which looks to me like the sanding belt that I've used with good success so far. The grit on the sanding belts isn't just a surface layer like friction tape products, instead it is incorporated in resin.

Regarding the Qiroll roller size - since they sell only one version of replacement friction tape it would seem that the rollers for the Mute and Pro are the same circumference. Otherwise they would offer two different varieties, one for each version.
 
Thanks! Ever seen anyone mess with the switch to keep it on, then deactivate through hitting the brakes?
 
I haven't seen anything that was reported as sucessful. At one time I did see one blog post where someone was attempting a revision but provided no follow up - which makes me think that perhaps it didn't work out for him.
The S2 activation control leaves something to be desired.
 
I hope that the friction tape works well for you and you post up your experiences one way or the other. I've mentioned before that it didn't work for me. I started with a generic product, then 3M Safety Walk and finally Gorilla brand. The grit on all three quickly wore off exposing the underlying tape with slippage. From what I gather from 3dxl's posts he presses the roller very hard on the tire while I followed the Qiroll instructions regarding pressure of the roller on the tire so that might have been the difference. If you check the GBoost product page for their friction drive you can see what they use instead, which looks to me like the sanding belt that I've used with good success so far. The grit on the sanding belts isn't just a surface layer like friction tape products, instead it is incorporated in resin.

Regarding the Qiroll roller size - since they sell only one version of replacement friction tape it would seem that the rollers for the Mute and Pro are the same circumference. Otherwise they would offer two different varieties, one for each version.
Yes, i pressed the roller really hard so that it won't slip and won't worn out the tape, consequently startup pedaling can be a bit stiff but get easier to pedal when it gain rolling momentum. Yeah, i didn't follow Qiroll recommended setting. Another thing is that if the tape exposed to water the tape abrasion will worn out faster if you allowed it to slip.
 
Here is a link, not what you are asking for:
Apparently he was trying to incorporate a cadence sensor and brake cut out.
That's me, it does work. Somebody else seemed interested in accomplishing the same thing but with a microcontroller, and they also did some cool investigation of the qiroll itself.

Coincidentally I recently moved to the bottom of a steep hill -- currently running a very silly 2x Pro configuration (one mounted under the BB, one off the seatstays), but even that can't maintain enough friction if it's even the least bit damp. Road bike with 28c max tires unfortunately, not a lot to work with. Might give the grip tape a go, just shredded one of the stock friction strips on a ride.
 
Well, I decided to 'cycle a different path' after reading the helpful posts here:

TSDZ8 750W 48V Motor - 44T VLCD5 Throttle + Brake Sensors
48V 12.8AH Rack Battery - LG MH1 Cells - Refurbished

I pre-ordered the 750W (more coming next week) over the phone while speaking with the owner, Myles. Super friendly and knowledgeable person. His company is very competent in e-bike and battery building.


I am looking forward to conquering these steep hills! 🚴‍♂️
 
Thanks for the reply, beyond my ability to replicate what you did but might be something that someone else could accomplish. Do you have any suggestions regarding Tuono's switch alteration question?

Regarding the friction tape, it sounds like most Qiroll users have similar issues with the stock tape. If the grip tape doesn't work out for you before thowing in the towel you might want to try a sanding belt - it worked for me anyway (with the lower power Mute).
 
That's me, it does work. Somebody else seemed interested in accomplishing the same thing but with a microcontroller, and they also did some cool investigation of the qiroll itself.

Coincidentally I recently moved to the bottom of a steep hill -- currently running a very silly 2x Pro configuration (one mounted under the BB, one off the seatstays), but even that can't maintain enough friction if it's even the least bit damp. Road bike with 28c max tires unfortunately, not a lot to work with. Might give the grip tape a go, just shredded one of the stock friction strips on a ride.
I re-read your posts from back in 2022 and see that you are the one who also reported that the Pro wouldn't run on >38v which is only 3v above the 35v charger for the stock 33v Pro battery. Maybe 36v would work (two 18v power tool batteries in series)?. I've run my 24/25v Mute version on 24v using a Buck step down along with a 36v nominal battery and it seemed a bit more powerful than running the stock battery but that impression might not be accurate. It also seemed a bit more powerful using shorter larger gauge 16g wires with the MR30 connectors rather than the excessively long stock 18g wires, again my impression might not reflect reality.
If I come across a used Pro for sale I might give it a try to compare with the Mute which, for where I ride, is underpowered.
 
Thanks for the reply, beyond my ability to replicate what you did but might be something that someone else could accomplish. Do you have any suggestions regarding Tuono's switch alteration question?

Regarding the friction tape, it sounds like most Qiroll users have similar issues with the stock tape. If the grip tape doesn't work out for you before thowing in the towel you might want to try a sanding belt - it worked for me anyway (with the lower power Mute).
IMG_9173 Large.jpeg

Well something like the bottom schematic would accomplish that, assuming that the brake sensor works like the ones I've encountered. (Top one is just the stock Qiroll). Brake sensor to ground on one side and a pullup resistor to VCC(3.3V) on the output. When braking, the sensor will pull the output to ground. Unfortunately this is the opposite of what you want, since pulling the Qiroll's throttle input to ground is what activates the motor.

So you'd need a NOT gate of some sort, whether you make it out of a transistor and a couple resistors or a logic IC. Also note the voltage regulator off the battery, you hardly need any power so a linear reg is fine but you do need something (ideally with those capacitors on the input and output). I used this series before I went surface-mount: https://www.digikey.com/en/products/detail/diodes-incorporated/AP7381-33V-A/7802342

Also if you get a dual NAND gate, you could arrange the logic so the switch still works. When you want it to run nonstop except when braking you could wrap a rubber band or something around the switch (lol), or replace the switch with a slider/latching button instead of momentary. When you only want assist sometimes, you could take the rubber band off/actively manipulate the switch and it would control (with the brake cutout still there as a backup). https://www.digikey.com/en/products/detail/texas-instruments/CD40107BE/376603

Actually you might have to go with the second option -- AFAIK if you plug in the Qiroll with the throttle held down (which is what the NOT circuit would look like) it errors?

edit: don't forget a pullup resistor at the first NAND gate inputs either, forgot to draw it in.

IMG_9174 Large.jpeg
 
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I re-read your posts from back in 2022 and see that you are the one who also reported that the Pro wouldn't run on >38v which is only 3v above the 35v charger for the stock 33v Pro battery. Maybe 36v would work (two 18v power tool batteries in series)?. I've run my 24/25v Mute version on 24v using a Buck step down along with a 36v nominal battery and it seemed a bit more powerful than running the stock battery but that impression might not be accurate. It also seemed a bit more powerful using shorter larger gauge 16g wires with the MR30 connectors rather than the excessively long stock 18g wires, again my impression might not reflect reality.
If I come across a used Pro for sale I might give it a try to compare with the Mute which, for where I ride, is underpowered.
Yeah, that was my experience. At first my homemade battery was 10s3p, so 42V at max charge. The stock Pro/H70 batteries are 9s3p, nominally indeed about 33V but at max charge they're up to 37.8V, which is what my stock charger outputs.

Those stock wires are indeed long, wouldn't be surprised shorter wires make a difference. Interesting about the buck converter, I thought about it for mine but decided to keep it simple. I guess if it's rated for the current... could be OK?
 
Oh that reminds me, I put my cadence sensor kit on a friend of a friends bike and it tested fine at my place. Well, they try and ride it and complain it doesn't work. They brought it back to my place, again worked fine in the stand. I try and ride it and yeah they're right, doesn't work.

It was a small bike and they had the battery close to the motor, so I wrapped the stock battery wire around the frame. Also ran the cadence sensor wire on top of that coil. Anytime the motor drew actual power to accelerate... it created enough electromagnetic interference to disable the cadence sensor. Didn't happen in the stand since the wheel didn't need much power to spin in air lol
 
Buck converter worked for me. Enclosed in a handlebar bag it didn't even get warm. Since these motors draw low current there are Buck converters for the load. I did find a 36v output Buck 10a max (not sure what continuous it would support) that might work with a pro but I'm more wanting to try with power tool batteries
 
View attachment 185245
Well something like the bottom schematic would accomplish that, assuming that the brake sensor works like the ones I've encountered. (Top one is just the stock Qiroll). Brake sensor to ground on one side and a pullup resistor to VCC(3.3V) on the output. When braking, the sensor will pull the output to ground. Unfortunately this is the opposite of what you want, since pulling the Qiroll's throttle input to ground is what activates the motor.

So you'd need a NOT gate of some sort, whether you make it out of a transistor and a couple resistors or a logic IC. Also note the voltage regulator off the battery, you hardly need any power so a linear reg is fine but you do need something (ideally with those capacitors on the input and output). I used this series before I went surface-mount: https://www.digikey.com/en/products/detail/diodes-incorporated/AP7381-33V-A/7802342

Also if you get a dual NAND gate, you could arrange the logic so the switch still works. When you want it to run nonstop except when braking you could wrap a rubber band or something around the switch (lol), or replace the switch with a slider/latching button instead of momentary. When you only want assist sometimes, you could take the rubber band off/actively manipulate the switch and it would control (with the brake cutout still there as a backup). https://www.digikey.com/en/products/detail/texas-instruments/CD40107BE/376603

Actually you might have to go with the second option -- AFAIK if you plug in the Qiroll with the throttle held down (which is what the NOT circuit would look like) it errors?

View attachment 185246
So allow me to show my ignorance. If the Qiroll switch is normally open couldn't you just put a simple in-line on/off switch in series with a normally closed brake cut off switch and avoid having to use a NOT gate (I'm not sure if there are normally closed brake cut off switches but I've read that there are)? Would have to know what wires route to the throttle vs mode switch. I don't think that I'd do this myself but Tuono brings up an interesting Q.
 
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