Convert Q45 to ebike

Black Hawk Down

Senior Rookie
Has anyone tried to convert the Q45 to and ebike using a front wheel conversion package on the back wheel of the Q45? I can't seem to find a package that will work with thru-axles. I previously converted my S40 to an ebike using the following kit that I purchased on Amazon:

48V 500W Front Hub Motor Electric Bike Conversion Kit for 26inch Wheel Drive Engine with Display with Battery (C18,Rear Battery 48V 17.5Ah)

I used the bike in a 2400 mile tour and it worked great. The S40 has QR dropouts so there were lots of ebike kits available. Seems no one provides one for thru-axles. I have sent a query to Grin Technologies' as they look promising but that seems to be the only possibility at this point.

For the Q45, I would like a 250W motor with a large 36V battery as I wan't it to meet EU requirements for ebikes.

Thanks,
Bill
 

Robert Holler

Administrator
Staff member
A front through axle motor hub is the holy grail but sadly there are basically none. Literally. There are no manufacturers really making them.

At the Taipei Cycle Show this last spring we saw ONE manufacturer that had designed a VERY COOL front hub that rose insanely smooth and was all inclusive with built in replaceable battery, was brushless, silent, etc etc - but it was not through axle and it was not a disc brake hub. They did say that they "could" make it as a through axle hub - but that was the sales rep talking. When I talked to the actual engineer he pretty much laughed that idea out of the window so... there you go.

On a through axle Q you would have to do a rear hub up front with a cadence sensor in the BB - that would work. Not ideal but could work as there are 142 through axle e-hubs.
 

Black Hawk Down

Senior Rookie
A front through axle motor hub is the holy grail but sadly there are basically none. Literally. There are no manufacturers really making them.

At the Taipei Cycle Show this last spring we saw ONE manufacturer that had designed a VERY COOL front hub that rose insanely smooth and was all inclusive with built in replaceable battery, was brushless, silent, etc etc - but it was not through axle and it was not a disc brake hub. They did say that they "could" make it as a through axle hub - but that was the sales rep talking. When I talked to the actual engineer he pretty much laughed that idea out of the window so... there you go.

On a through axle Q you would have to do a rear hub up front with a cadence sensor in the BB - that would work. Not ideal but could work as there are 142 through axle e-hubs.
Thanks Robert. I can't do a rear motor up front as I have a Rohloff speedhub. I'm still hoping for Grin Technologies as they have thru-axle front wheel options on their website. Unfortunately, I'm looking for a 250W motor and their front thru-axle versions on the website are 500W-1000W. I sent them a message asking to quote me a package. We'll see what they come up with.
 

Boreen bimbler

Well-Known Member
I looked into it and only found Grin. It seems the wires usually come out of the end of the axle so not a compatible thing with thru axles.
My health is my limiting factor for touring (the reason I looked into it) but I decided I might as well just get a motorbike for the job than import a Grin hub. Although I'm very comfortable with cycle mechanics the electric side baffles me and I worry about making an expensive mistake.
 

Bo6

Well-Known Member
Thanks Robert. I can't do a rear motor up front as I have a Rohloff speedhub. I'm still hoping for Grin Technologies as they have thru-axle front wheel options on their website. Unfortunately, I'm looking for a 250W motor and their front thru-axle versions on the website are 500W-1000W. I sent them a message asking to quote me a package. We'll see what they come up with.
I am considering electrifying my Q45 and will follow your progress. I was about to email Grin, but will see what you come up with first. A friend has used them on a DF conversion and she was very pleased with the service.
 

Robert Holler

Administrator
Staff member
Grin now looks to have a 12x100mm through axle front hub - that TECHNICALLY could work on the back of a Q45 - though I cannot say for sure, as I have only looked at it briefly, but it looks to be the only actual through axle front hub motor I have seen so far. I am not exactly sure how the torque arm would attach but probably possible to fix it in a position that would work.



Robert
 

SailRider

New Member
I successfully converted a 2021 Q45 using the Grin All-Axle front hub motor in 2023. I followed the tips in this thread: https://forum.cruzbike.com/threads/electric-2021-q45.14218/page-2

Particularly, I got tips in this forum thread on handling the torque arm attachment and on modifying the cadence sensor (Bret’s method). I put the torque arm on top of the rear stay as opposed to below, as Bret did. I used stainless steel zip ties with shrink wrap sleeves to secure the torque arm. I cut a piece of dense foam to fit the contours of the rear stay where the torque arm shoe seats against it. I have not had any issues with the cable exiting the hub. I did purchase and use, without modification, Grin’s brake rotor due to this concern. I use Grin LiGo 36 volt batteries that I share with a previously converted Bike Friday tandem and carry them in a bag.



Here's what I got from Grin Technologies (ebikes.ca):

Grin All-Axle Ready-To-Roll Kit
SKU: KIT-Grin_RTR
1​
USD$1,390.20​
Motor Winding Choice
1 x GrinHub_SL_Bk USD$595.00
Torque Arm Model
1 x Grin Hub Torque Arm Kit USD$30.00
Include Disk Rotor? (SOME 3rd PARTY ROTORS WILL DAMAGE CABLES!)
1 x Magura Storm HC 6-Bolt Rotor 160 USD$42.00
Axle Adapter Choice
1 x 12mm Thru Axle Adapters USD$10.00
32 Hole Rim for Custom Wheel Build?
1 x Rim275_Alex_32H USD$30.00
Include Custom Cut Spokes?
32 x Sapim Strong 13-14g Butted Spoke, Black USD$2.00
Have Grin do Wheel Build?
1 x WheelBuild USD$60.00
Controller
1 x Phaserunner L10 Black USD$350.00
Motor Extension
1 x L10 Extension Cable (60cm) USD$20.00
V3 Cycle Analyst
1 x CA3-WPx USD$115.00
CA Mounting Bracket Style
1 x Handlebar clamp for CA/CA3/Front Lights USD$15.00
Auxiliary Input and Power Switch
1 x CA3_MFSwitch for CA3-WPx USD$20.00
Pedal Sensor Type
1 x 24 Pole PAS (Long 120cm Cable) USD$24.00
eBrake Levers for Regen?
1 x Dual Ebrake Levers (50cm Cable) USD$24.00
Inject motor with Statorade?
1 x Inject Motor with Statorade USD$20.00
Thumb Throttle, Clamp. Long Cable (140cm Cable)
SKU: T-T-CLever
1​
USD$22.00​
Subtotal​
USD$1,412.20​
Shipping & Handling​
USD$202.62​
Grand Total (Excl.Tax)
USD$1,614.82
Tax​
USD$0.00​
Grand Total (Incl.Tax)
USD$1,614.82
 

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  • EConvert Torque Arm Clamping.JPG
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Mascottrepair

New Member
Hi Bill,
You're right—thru-axle-compatible hub motors are hard to find. Most ebike kits target QR setups. Grin Technologies is your best bet, especially with their custom solutions. Hope they can help!
 

Black Hawk Down

Senior Rookie
I am considering electrifying my Q45 and will follow your progress. I was about to email Grin, but will see what you come up with first. A friend has used them on a DF conversion and she was very pleased with the service.
I completely struck out with a Q45 eBike conversion. I haven't heard back from Grin so there may be some hope there. I see some other posts here that give Grin some hope. I'll look into this later when I'm more in the mood.
 

Black Hawk Down

Senior Rookie
I successfully converted a 2021 Q45 using the Grin All-Axle front hub motor in 2023. I followed the tips in this thread: https://forum.cruzbike.com/threads/electric-2021-q45.14218/page-2

Particularly, I got tips in this forum thread on handling the torque arm attachment and on modifying the cadence sensor (Bret’s method). I put the torque arm on top of the rear stay as opposed to below, as Bret did. I used stainless steel zip ties with shrink wrap sleeves to secure the torque arm. I cut a piece of dense foam to fit the contours of the rear stay where the torque arm shoe seats against it. I have not had any issues with the cable exiting the hub. I did purchase and use, without modification, Grin’s brake rotor due to this concern. I use Grin LiGo 36 volt batteries that I share with a previously converted Bike Friday tandem and carry them in a bag.



Here's what I got from Grin Technologies (ebikes.ca):

Grin All-Axle Ready-To-Roll Kit
SKU: KIT-Grin_RTR
1​
USD$1,390.20​
Motor Winding Choice
1 x GrinHub_SL_Bk USD$595.00
Torque Arm Model
1 x Grin Hub Torque Arm Kit USD$30.00
Include Disk Rotor? (SOME 3rd PARTY ROTORS WILL DAMAGE CABLES!)
1 x Magura Storm HC 6-Bolt Rotor 160 USD$42.00
Axle Adapter Choice
1 x 12mm Thru Axle Adapters USD$10.00
32 Hole Rim for Custom Wheel Build?
1 x Rim275_Alex_32H USD$30.00
Include Custom Cut Spokes?
32 x Sapim Strong 13-14g Butted Spoke, Black USD$2.00
Have Grin do Wheel Build?
1 x WheelBuild USD$60.00
Controller
1 x Phaserunner L10 Black USD$350.00
Motor Extension
1 x L10 Extension Cable (60cm) USD$20.00
V3 Cycle Analyst
1 x CA3-WPx USD$115.00
CA Mounting Bracket Style
1 x Handlebar clamp for CA/CA3/Front Lights USD$15.00
Auxiliary Input and Power Switch
1 x CA3_MFSwitch for CA3-WPx USD$20.00
Pedal Sensor Type
1 x 24 Pole PAS (Long 120cm Cable) USD$24.00
eBrake Levers for Regen?
1 x Dual Ebrake Levers (50cm Cable) USD$24.00
Inject motor with Statorade?
1 x Inject Motor with Statorade USD$20.00
Thumb Throttle, Clamp. Long Cable (140cm Cable)
SKU: T-T-CLever
1​
USD$22.00​
Subtotal​
USD$1,412.20​
Shipping & Handling​
USD$202.62​
Grand Total (Excl.Tax)
USD$1,614.82
Tax​
USD$0.00​
Grand Total (Incl.Tax)
USD$1,614.82
Wow! Thanks for all the info. Looks like a lot of work and is quite expensive. I may decide to go forward, but not for a year or so. Thanks for your help with this.

Bill
 

SailRider

New Member
Bill, the Grin kit (front through-axle hub installed in rear) was a simple install once I got past how to mount the torque arm and past holding my breath on cutting the flange off the cadence sensor. I've found Grin good to work with, though I haven't communicated with them since completing the conversion two years ago. -- Mark
 

Black Hawk Down

Senior Rookie
Bill, the Grin kit (front through-axle hub installed in rear) was a simple install once I got past how to mount the torque arm and past holding my breath on cutting the flange off the cadence sensor. I've found Grin good to work with, though I haven't communicated with them since completing the conversion two years ago. -- Mark
Ok. Thanks Mark.
 

danhunt56

Member
I have a Quest with drop axel and used a bafang front hub motor that I absolutely love. The whole kit without a battery only cost about $300. If I get a modern Q45 I would have to use a thru axel motor. I found the Grin as reported already. Recently I found another company. https://www.google.com/aclk?sa=L&ai...zu-54b-PAxUs9rsIHRQiHeYQwg8oAHoECAkQGQ&adurl=

Edit: I coulda sworn I found a front motor on their site that was thru axel but not now.

I love the two wheel drive, but have heard that a midmotor mounted in the moving bottom bracket works well. Toseven DM02 is a small light weight motor. 250-500 watt motors are available @ 36 to 60 volts. I have them on my rear wheel drive recumbents. I prefer the hub motor as it is easier to manage the relationship between pedaling and motor assist. The midrive has the advantage in that you can downshift it as it uses the same drive train as you. They should work better for long steep assents.
 
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Black Hawk Down

Senior Rookie
I love the two wheel drive, but have heard that a midmotor mounted in the moving bottom bracket works well. Toseven DM02 is a small light weight motor. 250-500 watt motors are available @ 36 to 60 volts. I have them on my rear wheel drive recumbents. I prefer the hub motor as it is easier to manage the relationship between pedaling and motor assist. The midrive has the advantage in that you can downshift it as it uses the same drive train as you. They should work better for long steep assents.

I would not attempt a MBB mid motor unless I saw that several people have tried it and found it to work well. Too much mass on the front end. I'm skeptical.
 

danhunt56

Member
I would not attempt a MBB mid motor unless I saw that several people have tried it and found it to work well. Too much mass on the front end. I'm skeptical.
I have read of several successful installs using a mid motor. I could use an inexpensive bafang front hub on my older Quest so I went with that. It turns out to be perfect for very steep long hills I regularly ride and improves off-road performance due to no wheel slippage. If I pick up a Q45 with thru axel I will try one of my midrives first. I have some ideas for making a conversion kit to use a drop axel motors on the rear of a thru axel cruzbike. As of yet I only have the Quest and other drop axel bikes so I can not experiment. But it does not look impossibile and would mount the wheel back behind the the present mount.
 

Black Hawk Down

Senior Rookie
I have a front motor Bafang on the rear of my (QR axle) S40 and it works well. I'm curious. Do you use a thumb throttle, a grip throttle or pedal assist? I use a thumb throttle but it's real hard on my thumb as it's too stiff. I use rubber bands to preload it, but it's not a great solution.

As far as the "several successful installs" of a mid-motor, doesn't really address the likely heavy action on the MBB. Sure you can install it, but is it comfortable with all that weight at the front? I imagine front wheel flop will be much worse.
 

danhunt56

Member
I mean successful in that the riders like them. As for fork flop I solved that by installing a motorcycle steering damper, it slows the flop and acts as a steering stop so that it does not over steer which often knocked the bike off its kickstand. I don’t have a mid motor, but that would to me be a part of adding even more weight to the bottom bracket.
 

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bret

Well-Known Member
Looks like a lot of work

I no longer have the bike, but this popped up in my email about "what you missed".

The v3 Grin All-Axle motor has redesigned the cable outlet to avoid the problem of the brake rotor cutting the cable. The special left side adapter I had made for the v2 motor is probably not needed now.

Apart from that, it is not much work at all. Most parts just bolt on, although the flange on the PAS sensor must be removed to fit onto the enlarged bottom bracket. I still prefer my own approach to seating the torque arm.

The motor in the rear works very well on hills. Just as it's possible to slip the front tire pedaling up a hill, the motor in the front can do the same. There is no loss of traction from the rear mounted motor - all the weight is in the right place.

Pay attention to the motor winding variant (STD, FST, SLO) as it matches against the speeds you want to ride at. Grin discusses this in the dedicated page for the All-Axle, and Grin also provides a Motor Simulator tool page which you can use to investigate how the motor will perform.

The Robert Axle Project will sell you a thru-axle and spacers to permit adding a trailer hitch to the rear as well.
 
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