dangerzone
New Member
- Region
- Australia
Thanks for the info. It's certainly neater than the zip tie, bent coat hanger and springs from an IKEA desk lamp contraption that I had going on before
REVIEW: QR-E 250W ELECTRIC BOOSTER BICYCLE MOTOR AND B60i AND B70 BATTERY
- Thread starter ebike
- Start date
Thanks for the info. It's certainly neater than the zip tie, bent coat hanger and springs from an IKEA desk lamp contraption that I had going on before
Charlie Pendejo
New Member
- Region
- USA
Ha, I understand your lesson only too well.
Just had an email exchange with the 3d printer (which I farmed out via a site called craftcloud) - at first it sounded like there was some weird problem and he needed me to revise the CAD model, but I think we've clarified that there's just a rough edge which could use a little filing and sanding, and he'll ship it soon.
It's only my second go-round with CAD & 3d printing. The first was for a nylon shim which sat between QiRoll's Strida adapter and my tandem's smaller-diameter tube. The shim itself turned out fine, it just wasn't a great mounting arrangement on my bike,
Just had an email exchange with the 3d printer (which I farmed out via a site called craftcloud) - at first it sounded like there was some weird problem and he needed me to revise the CAD model, but I think we've clarified that there's just a rough edge which could use a little filing and sanding, and he'll ship it soon.
It's only my second go-round with CAD & 3d printing. The first was for a nylon shim which sat between QiRoll's Strida adapter and my tandem's smaller-diameter tube. The shim itself turned out fine, it just wasn't a great mounting arrangement on my bike,
Still trying alternatives to the stock control switch. This time using latching pushbutton switches instead of temporary blade. The mode button can remain latched for the regen function or blipped on then off to switch between low and high assist levels. The other button to actuate boost will stay on until switched to off so I might wire in one of the normally closed brake switches repurposed from my burned out non-Qiroll friction drive to cut assist while braking without having to use the push button.
Hey Guys
I have a new Qiroll Flex that I won't be able to use in my area with big hills. It has maybe a mile on it, roller is clean - no wear, comes with a roll of abrasive tape and a 6 mo waranty from Jason at Qiroll. LMk if anyone has any interest. I live in San Diego.
I have a new Qiroll Flex that I won't be able to use in my area with big hills. It has maybe a mile on it, roller is clean - no wear, comes with a roll of abrasive tape and a 6 mo waranty from Jason at Qiroll. LMk if anyone has any interest. I live in San Diego.
Charlie Pendejo
New Member
- Region
- USA
Getting close. 3D printed adapter seems fine, and simply bolting it to a stretchy velcro-based strap seemed like it'd be plenty secure on the bike. But the strap's flexibility gave the assembly too much freedom to easily rotate in multiple planes (viewed from above, viewed from the side of the bike).
I'll have another go with a nylon ratchet strap which should arrive tomorrow. The ones I already had turned out to be much narrower than I recalled.
I'll have another go with a nylon ratchet strap which should arrive tomorrow. The ones I already had turned out to be much narrower than I recalled.
Charlie Pendejo
New Member
- Region
- USA
Predictably this project has me repeating "this is why I'm a software guy."
Bolted hinge/motor assembly to strap
But even this non=flexible nylon strap, tightened as much as I could manage on the bike, twisted a lot with the tension of the spring hinge. Clearly I either needed to use a very rigid strap - like the hose clamp EMGX suggested earlier - or, the light bulb went off, give this hinge assembly enough length so that I could anchor it in two places, front and back. I had some scrap wood nearby, formerly louvers on a closet door. Cut a piece and bolted the hinge to it.
Even my very stretchy velcro-based straps hold this reasonably securely, wrapped around both the front and rear of the assembly. Good enough for a short test ride, though I think a cleaner, more secure solution will involve bolting this to a universal bottle cage mount I have, which I've confirmed will strap firmly where it'd need to go on the bike's frame.
The problem that quickly arose surprised me: my 3D printed hinge-to-motor adapter snapped in half! Apparently the "tough resin" material I selected for this part isn't tough enough.
Maybe I should just find a way to drill holes (or have holes drilled, so I can avoid accumulating more tools I'll use exactly once) in the hinge so I can attach it directly to the motor without need for an adapter.
Bolted hinge/motor assembly to strap
But even this non=flexible nylon strap, tightened as much as I could manage on the bike, twisted a lot with the tension of the spring hinge. Clearly I either needed to use a very rigid strap - like the hose clamp EMGX suggested earlier - or, the light bulb went off, give this hinge assembly enough length so that I could anchor it in two places, front and back. I had some scrap wood nearby, formerly louvers on a closet door. Cut a piece and bolted the hinge to it.
Even my very stretchy velcro-based straps hold this reasonably securely, wrapped around both the front and rear of the assembly. Good enough for a short test ride, though I think a cleaner, more secure solution will involve bolting this to a universal bottle cage mount I have, which I've confirmed will strap firmly where it'd need to go on the bike's frame.
The problem that quickly arose surprised me: my 3D printed hinge-to-motor adapter snapped in half! Apparently the "tough resin" material I selected for this part isn't tough enough.
Maybe I should just find a way to drill holes (or have holes drilled, so I can avoid accumulating more tools I'll use exactly once) in the hinge so I can attach it directly to the motor without need for an adapter.
Your hinge looks like it might be galvanized/zinc steel which should drill fairly easily with standard drill bits if they're sharp. If it's stainless then cobalt bits might be necessary (Home Depot has a sale on a good looking Milwaukee cobalt drill set this weekend). Use a center punch to mark the spot you want to drill otherwise the drill bit will tend to wander. I hope the fabric strap you use will work for your application but a stronger more stable attachment might be needed. Good luck with your project, I hope you get it to work for you.
Last edited:
Charlie Pendejo
New Member
- Region
- USA
Thanks. Stainless, and confirmed my cheapo "high speed" bits got nowhere. I had +some 1/4" aluminum intended to make a sturdy platform, and had plenty extra to fashion a hinge-to-motor adapter.
This assembly now feels rock solid. But you're right about needing a more stable attachment than anything I've tried so far, including the two-strap bottle cage adapter I currently have this bolted to. After tightening those straps it felt reasonably secure, statically, requiring a fair bit of force to nudge it out of position. But moving the pedal through a few revolutions, causing the bike wheel & motor wheel to rotate, has the assembly rotating toward and eventually into one of the cranks it's nestled between.
This assembly now feels rock solid. But you're right about needing a more stable attachment than anything I've tried so far, including the two-strap bottle cage adapter I currently have this bolted to. After tightening those straps it felt reasonably secure, statically, requiring a fair bit of force to nudge it out of position. But moving the pedal through a few revolutions, causing the bike wheel & motor wheel to rotate, has the assembly rotating toward and eventually into one of the cranks it's nestled between.
Does your spring hinge hold the roller tight enought on the tire to prevent slipping especially in the high setting?
I tried my Qiroll on a 20" folder riding a gravel rails to trails. Qiroll did fine but 20" folder wasn't a good bike choice on this sometimes loose and bumpy gravel. Fun few days anyway.
Last edited:
$200 Walmart folder I bought many years ago to put in the back of my car and ride a gravel dike path after work. Rode after dark in the winter with coyotes and deer for company, eyes glinting from my headlamp. Was a good ride for limited distances on gravel.
I like the bike and wanted to give it a longer distance gravel try after reading that bike friday and brompton have marketed 20" folder "gravel" bikes. Not the right tool for the job for other than shorter rides IMO. Was contemplating taking it on the Mickelson trail in SD but after this experience I'm taking a large wheel bike.
I like the bike and wanted to give it a longer distance gravel try after reading that bike friday and brompton have marketed 20" folder "gravel" bikes. Not the right tool for the job for other than shorter rides IMO. Was contemplating taking it on the Mickelson trail in SD but after this experience I'm taking a large wheel bike.
Charlie Pendejo
New Member
- Region
- USA
That's the 64 thousand dollar question I hadn't really considered until an hour ago when I attached this assembly once again to by bike and noticed the force holding motor to tire was less than I expected. Can't say for certain it was less pressure than in earlier attempts, but it was the first time in all this fiddling it occurred to me that it might be insufficient.
And the test ride confirmed it is too little force. Rotated fine with the wheel while pedaling normally, but pressing the boost button - even in eco mode - had it just spinning against the tire. And this is with rough carpet gripper tape, not the smoother stock stuff.
That's... a setback. I could play a little with front-back positioning of the assembly so that the hinge is at a little greater or lesser angle, but I really don't see this making enough difference. Spring force doesn't seem to be adjustable. When I began this project, I had some concern a door-closing hinge might be too strong for this application, not too weak.
Well, I have a little over two weeks before we take the bike on tour to figure out & execute a solution, which I very much hope to do. We can certainly ride without the motor and our route this summer (Toronto -> Ottawa -> Montreal) is pretty flat, but it's just a heavy, inefficient, shockingly slow bike... and I've planned our stops with the motor in mind, covering a little more ground than we're comfortable with in acoustic mode.
- -
The water bottle cage adapter has slots for 1/2" wide straps, which conveniently seems to be the standard width for hose clamps. I bought a kid which let me cut my own clamps to desired length. It took a few tries to work out to position and orient stuff in this tight space between two cranks and with other neighbors like brake/shifter cables, but once that was solved it was pretty straightforward. As expected, tightening these stainless clamps holds the assembly in place extremely securely. Nothing is moving a millimeter!
The adapter's original velcro-based straps work well for holding the hinge closed, to physically disconnect the motor from the tire, so when I bolted my platform to the adapter I slid one of those straps in between..
I had also drilled a couple more holes in my aluminum platform, to try the standard "clamp to chain stay" method:
but between the cable guides and the irregular welded joint, I couldn't get it to lie flat and securely. Though in theory I now have a more universal hinge/motor assembly - if only I can get it to actually, you know, work! - with both chain stay and bottle cage mounting options, so I could I could move it to my road-ish/randonneur bike.
And trying to get this to work emphasized how shockingly out-of-round this bike's rear wheel is! Had this thing (inadequately) mounted in a position that gave several mm of clearance, only to have the tire rub & get stuck along the platform's edge after half a rotation. Seems like the mounting the motor on a spring/hinge should allow it to follow the contour far better than fixed/rigid mount.
Also want to mention, in case it's useful to anyone attempting something similar: there's plenty of places who will laser cut aluminum (or stainless, etc.) and would've done a neater job than I managed, and saved me acquiring a few tools. I chose to DIY to have more control over the timing: I was getting nervous about having everything finished before our end-of-June trip. (Of course I remain nervous, with still no working solution...)
Last edited:
I agree that a spring hinge seems like the best mounting option for no other reason than that tires/wheels often aren't perfectly round circumferentially so with a static mount the motor pressure on the tire fluctuates which allows slipping. I've used a few different spring hinges and found that the 4" with adjustable tension works the best (if there is room for it) because it can be cranked up to much higher tension than the smaller hinges. I can't see if you would have enough room for the 4" hinge without interferring with the chainrings on your bike but if there is enough room you might be able to attach one to your aluminum adapter plate. Because of the barrel of the hinge you would need a spacer so the hinge sits flat on your adapter plate. I've used adhesive solid neoprene for the spacer but just about any noncompressible material should work.
Charlie Pendejo
New Member
- Region
- USA
Thanks yet again. It makes sense the 4" version would be stronger than the 2.75" I'm using. Two reasons not to switch:
(a) It's too clean and sensible, not something one would call "crackpot" or "harebrained." It'd feel too out of character.
(b) And oh yeah, there's only about 3.55" between chainrings. I could probably fit a 3" hinge in there, but wouldn't expect sizing up 1/4" to give that much more juice.
Adding supplementary pull from the rear seemed like far & away the simplest thing to try, so I tried it. First I bolted a short bit of stretchy strap + buckle to the motor assembly:
And when I'd finally added enough pressure for the motor to retain grip in boost mode, it was with a daisy-chained pair of reusable zip ties, hooked through a slot in a steel adapter which holds the rear fender:
I may try to refine this a bit, perhaps replacing the zip ties with a strap and routing between fender & seat stay... but at least I've arrived at something that has worked well for a quick jaunt around the neighborhood. This weekend I'll aim to get out with the kiddo for a longer 15+ mile shakeout ride.
Today's other surprise was only getting my new (purchased a year ago but unused until now) S2 switch to work very sporadically, like 1 try in 10. Old one still works, though it got damaged in touring 2 summers ago - it needed resoldering and I lost the front face of the "box" which surrounds the switches. I'll troubleshoot later, and at least have enough parts that I should be able to put together one complete & functional S2. Or maybe this is a sign from the universe to try and put together my own control including a boost switch that can stay on once toggled.
(a) It's too clean and sensible, not something one would call "crackpot" or "harebrained." It'd feel too out of character.
(b) And oh yeah, there's only about 3.55" between chainrings. I could probably fit a 3" hinge in there, but wouldn't expect sizing up 1/4" to give that much more juice.
Adding supplementary pull from the rear seemed like far & away the simplest thing to try, so I tried it. First I bolted a short bit of stretchy strap + buckle to the motor assembly:
And when I'd finally added enough pressure for the motor to retain grip in boost mode, it was with a daisy-chained pair of reusable zip ties, hooked through a slot in a steel adapter which holds the rear fender:
I may try to refine this a bit, perhaps replacing the zip ties with a strap and routing between fender & seat stay... but at least I've arrived at something that has worked well for a quick jaunt around the neighborhood. This weekend I'll aim to get out with the kiddo for a longer 15+ mile shakeout ride.
Today's other surprise was only getting my new (purchased a year ago but unused until now) S2 switch to work very sporadically, like 1 try in 10. Old one still works, though it got damaged in touring 2 summers ago - it needed resoldering and I lost the front face of the "box" which surrounds the switches. I'll troubleshoot later, and at least have enough parts that I should be able to put together one complete & functional S2. Or maybe this is a sign from the universe to try and put together my own control including a boost switch that can stay on once toggled.
Charlie Pendejo
New Member
- Region
- USA
I may well do that, and having assembled some amp & preamp kits over the decades, soldering's more in my wheelhouse. Do you know where I can find a wiring diagram / description?
Another connector fairly near the control end would add a lot of convenience: I could simply disconnect the cable before removing the handlebars, as part of folding & bagging the bike. That probably would've saved my original S2 from getting damaged when I packed the bike to bring on a train or bus.
Poked around both Amazon and AliExpress looking for handlebar-mountable switches with both a latching switch (for boost) and a momentary switch (for mode). They exist, often intended for headlight + a horn, but most are either for 22mm mountain bars (I have 25.4 drops) or cost more than I want to spend.
Another connector fairly near the control end would add a lot of convenience: I could simply disconnect the cable before removing the handlebars, as part of folding & bagging the bike. That probably would've saved my original S2 from getting damaged when I packed the bike to bring on a train or bus.
Poked around both Amazon and AliExpress looking for handlebar-mountable switches with both a latching switch (for boost) and a momentary switch (for mode). They exist, often intended for headlight + a horn, but most are either for 22mm mountain bars (I have 25.4 drops) or cost more than I want to spend.
Blueberry posted the wiring info which I followed, it's pretty simple.
I didn't want one of the handlebar mounted switches because they limit placement. Just ordered some rocker switches to try those out, cost $3.99 including shipping for 5 of them on Amazon. I wanted latching so I could activate regen without having to hold the button, just blipping a switch on/off works for changing power mode. I'm going to wire a brake cut off switch in line with the boost button for safety because I have one but that probably isn't that important.
I didn't want one of the handlebar mounted switches because they limit placement. Just ordered some rocker switches to try those out, cost $3.99 including shipping for 5 of them on Amazon. I wanted latching so I could activate regen without having to hold the button, just blipping a switch on/off works for changing power mode. I'm going to wire a brake cut off switch in line with the boost button for safety because I have one but that probably isn't that important.
I made up another switch using latching rocker switches. I think I'll stick with this and may or may not add a brake cut out.
The 6 ft usb micro extensions I have (came two in a pack, for ~$8 back when I bought them) have 4 wires, red (not used), black (common ground), green (corresponds to the mode/regen switch) and white (corresponds to the power switch). I'm not sure if all manufacturers use the same color coding so YMMV.
The 6 ft usb micro extensions I have (came two in a pack, for ~$8 back when I bought them) have 4 wires, red (not used), black (common ground), green (corresponds to the mode/regen switch) and white (corresponds to the power switch). I'm not sure if all manufacturers use the same color coding so YMMV.
Blueberry, if you still check in on this thread, where did you see that they (Qiroll?) say B70 batteries can be used with the Pro? I did message them and all they messaged back is the generic statement that the H70 is for the Pro and the B70 is for the Mute. I ended up buying a Pro and did try the B70 battery from my Mute just to see if it works, which it did but it was just a short test run. I'm planning on riding the Mickelson trail in South Dakota next week (weather permitting) and taking the B70 battery along as a power bank and as a standby for the Qiroll but don't want to run it on low voltage if it could overheat or otherwise damage the motor.
Charlie Pendejo
New Member
- Region
- USA
Nice. My S2 seems to be working reliably, and with other issues arising + our Montreal -> Ottawa -> Toronto ride coming up quick, I put any switch plans on hold. And really, S2 + rubber band I can slide over the boost button is an arrangement I can live with for now.
Primary "other issue" = couldn't replicate my earlier success keeping the motor engaged with the tire. Applying boost caused the motor to spin freely, burning the grit off the carpet grip tape while starting to sand the tire's surface smooth. While reviewing this thread for info on wiring switches, stumbled across reports of others encountering similar and solving it by using belt sander tape for the tire interface. That seems to work well for me, though it sure would've been nice to discover this earlier and have a lot more testing in before our imminent tour! I'll make a handful of replacement tapes to bring with.
Primary "other issue" = couldn't replicate my earlier success keeping the motor engaged with the tire. Applying boost caused the motor to spin freely, burning the grit off the carpet grip tape while starting to sand the tire's surface smooth. While reviewing this thread for info on wiring switches, stumbled across reports of others encountering similar and solving it by using belt sander tape for the tire interface. That seems to work well for me, though it sure would've been nice to discover this earlier and have a lot more testing in before our imminent tour! I'll make a handful of replacement tapes to bring with.
Similar threads
