Radrunner (chilli with peppers)

asiero

New Member
Ciao, how is it going. After doing some reading, I have decided to write about my plans with the Radrunner EU version, which will basically focus on adding a little spice to the dish. I hope this is the right place in the forum to post it.

First, I must say that the Radrunner is a great bike, really cool and stuff, but I believe it falls short in power. I got it in May this year from the Rad Power Bikes importer in Holand, in the middle of the bloody COVID-19 crisis here in Italy, and as soon as the government let us out (after almost two months of confinement), I tested it on all types of roads with more or less slope. It goes nice and smoothly on level ground and relatively well on small slopes. Speed also kind of ok (some additional km/h wouldn't hurt anyway…). But on medium/steep slopes the bike just won't go. Either you pedal hard or you simply don´t arrive. Living in the north of Italy, Torino, a kind of mountainous area full of hills and slopes, this is an issue….. But please don´t get me wrong. I still recommend the Radrunner without any doubt. Unbeatable value for money in my opinion (in this line of bikes, I mean). Beyond the design and the quality of the electric parts, I particularly love the passenger package which allows you to comfortably carry people (on flat ground, of course). My little one also loves that part ;-)

Well, to the point. I decided to invest a little and spice it up. What I´m planning to do is surely not something that is strange to many of you, so any advice or comments are very welcome. I have some doubts so I leave also some questions along the way…

First, I´ll get a new controller and display. I think this is the easy part. I found two providers in the States, the usual suspects: Bolton Bikes and Electric Bike World (and surprisingly none in Europe). The controller and LDC displays they sell, cost and look similarly. I´ve also read that both sellers have tested their controllers in the Radrunner which are both plug and play (great!). The only challenge here I guess is to make the controller fit in the place where the original roadrunner controller is mounted. But I think that nor the Bolton neither the Electric Bike´s controller fits there…So I guess I´ll have to put it somewhere else… Any tips here are welcome…

Second thing is bringing on board a 750w Bafang hub motor. Here things get a bit complicated I think. I have read some posts and I´ve noticed that changing the motors can become a headache. It looks easy at first sight, as the idea in short is just to extract the motors from their respective cases and swap them. I´ve seen this in a couple of videos in youtube…But I read from Ccount (hi there!) that he was unable to get the chain to line up with the single gear threaded to the hub motor. The new motor came with a 7 gear cassette and Ccount noted that he resolved that issue getting the chain lined up on the 3rd gear on the cassette. I also read from rezonatefreq (Hi!) that the axle of the bafang 750w does not fit back into the frame of the radrunner (single speed). Both rezanotefreq and CCount got their 750w motors from Electric Bike World. So, summarizing I understand that rad runner´s motor is freewheel hub not cassette, so, does any one have a clue of where I can get one of those freewheel hub 750w motors? Or in case that is complicated, what is the best route here? Any tips?

Third thing is to get suspension forks but I'll leave that for now until I buy the other stuff (controller, display and motor)…first things first…
 
The only challenge here I guess is to make the controller fit in the place where the original roadrunner controller is mounted. But I think that nor the Bolton neither the Electric Bike´s controller fits there…So I guess I´ll have to put it somewhere else… Any tips here are welcome…
I have not done this upgrade myself (yet), but have inspected/measured my RadRunner 1 (RR1) for potential fit. It looks to me possible, in principle, to mount the Bolton/EBW controller to the underside of the bottom bracket, basically replacing the existing stock controller -- the space there is at least wide enough for the larger 35A controller (to fit between the chainring/cranks). However, mounting will likely require fabricating a custom bracket, or perhaps box, to match the existing mounting points.

As for the motor upgrade, I am aware of one potential installation issue: Several sources for the true 750W Bafang motor list a dropout width of 175mm, whereas Rad Power Bikes (RPB) lists the dropout width on the RR1 at 167mm. I believe there may also be a version of the Bafang motor with a dropout width of 190mm (so be careful which one you purchase). But as you mention, some Rad owners have reported difficulties because the motor axle is too long, and thus requires (potentially tricky) custom modifications.
As I further understand, these motors are offered in both a freewheel and cassette version -- you'll want the freewheel version for sure.
Another potential issue is removing the 16t single-speed freewheel from the stock motor. I have personally done this without using a special freewheel removal tool. Rather, I simply used a flat-headed punch and hammer to tap the freewheel loose without too much effort.
 
Aserio,
Hello and I look forward to hearing about your progress. To address some of your concerns, let me share some of my experiences. To date, my bike is running perfectly. I am still trying to dial in the controller settings to my liking, and I am trying to devise a progression chart which outlines what every setting does, what the possible variables are, and which settings may be related to other settings. Even though there are several basic charts out there, including Boltons video, it is no simple task to get things right. But I find it fun and challenging, so...

Regarding the controller, I bought a plastic controller box from Amazon, and was able to get the new controller to fit inside. It was necessary to cut away some of the internal ribs in the box, and I had to cut the 2 mounting tabs off of the ends of the controller to get it to fit into the plastic case. It was tight, but it worked, and I chose to seal the box to make it water proof, even though the controller is supposed to be water resistant. From there I was able to mount the controller and case where the existing one mounts, and was even able to re-use the skid plate for protection. If I recall correctly, I remounted the case with 2 long hose clamps, which I modified by putting heat shrink tubing on the "leg" of the clamp for looks and to protect the paint on the bike. Never have had an issue. I thought at first heat may be an issue, but I ride long and hard, in soft sand and such, and find myself in the 1000 watt territory often and for prolonged periods, and have never noted any, let alone excessive heat coming off of the controller box.

I guess I was just lucky when I ordered my motor, in that I got the one with the 7 gear cassette (or whatever it is called). As you commented, it would not have worked without it, as the existing gear was simply not lined up anywhere close. Yes, there was a very minor bit of bending required to the mounting bracket of the tensioner (dropout?) in order to get it perfectly aligned, but it seemed to be quite malleable and bent easily with no apparent issues. Thank goodness that part was not cast! I bought a few more from amazon, thinking I may need another in my current derailleur mounting project. I am in the process of adding a derailleur so I can change gears while pedaling, so the 7 gears will be useful while pedaling. I did have to manually spread the 2 fork ends a bit when inserting the new hub/wheel assembly, but frankly, it was not an issue. There were no frame modifications, drilling, or major fabrication needed. When i took my first test ride (the new controller and display had already been installed and used) the power was frightening! I gave it some throttle, and the bike instantly pulled a wheelie and went right out from under me! So I have developed some new riding habits, but I must admit I do like intentionally pulling a wheelie! There was no real change in speed, and none was expected.

I must admit removing the gear from the motor was a task. I tried cutting sockets, ordering specialty sockets on Amazon, and even taking it to several bike shops, with ho luck. However, I came up with a super easy solution: I took a robust pair of 90 degree needle nose pliers, and inserted the tips into the cavity on the nut, and pulled the pliers open while turning (counter clockwise I think). It worked like a dream! My next effort would have been to use a punch and hammer, but never needed to!

The Bolton suspension front end was a worthwhile addition! The ride is improved dramatically. As another person on the forum found, it was necessary to fabricate 2 metal tubular spacers in order to install the brakes, but that was very simple, and easy to figure out. Otherwise, everything just bolts on! I used stainless, and the other poster used brass I think. Brass looks better, but for me, I like the stainless. Even the fender braces mount, but did require some bending and shaping to fit.

As you may know, I also mounted a 1000w hub motor/wheel in front, with an individual twist throttle on the left handlebar end. With that motor alone I can get up to 30MPH, but acceleration is a bit slower than using the main motor only. Frankly, 30MPH is fast enough for me on that bike (I ride a KTM 1200 Adventure, which will go 175+, and I have had it to 140, so i like speed), but this bike seems pushed at 30. If I go to a 52v battery, I expect I could see 35 with the front motor, but I would rarely need or use that speed, and battery life is more important to me. There does not seem to be any gains when using both motors simultaneously, and I have tripped a thermal breaker or something likely in the BMS due to the very high (most likely 2000w++) draw. However, my intention was to devise a way to get through long stretches of soft sand on the beach, and it works like a charm. The front wheel alone simply spins in the sand, as there is no weight over that wheel for traction. But together (without a tremendous amount of throttle) it gets me through soft sand very well. Without the front tire motor engaged, the front wheel tends to plow into the sand instead of over it, and the bike "hunts" left to right almost uncontrollably.

Keep us updated!

Ccount
 
First, I´ll get a new controller and display. I think this is the easy part. I found two providers in the States, the usual suspects: Bolton Bikes and Electric Bike World (and surprisingly none in Europe). The controller and LDC displays they sell, cost and look similarly. I´ve also read that both sellers have tested their controllers in the Radrunner which are both plug and play (great!).
Another cheaper and easier option might be to find someone in the US who has already done the bolton controller upgrade, and buy their stock used radpower controller (and likely display) from them*. Given all the people saying that the radpower bafang 750w geared hub motor is really an overclocked 375w, it wouldn't surprise me if your "250w" motor is actually the same thing. It is often cheaper to manufacture the exact same hardware with various software limiters, thus the tales of the IBM mainframe tech with the golden screwdriver. Then you know the parts will fit, and don't have the hassle of swapping out a motor. If you do go this route, be aware that people are saying that sometime in 2020 radpower has dropped the max speed capability from 40 kph to 32 kph, so older is better.

Of course, if you want the full power of the drivetrain and the better power configurability, by all means go with aftermarket parts, but I would get the new controller/display first before buying a new motor. Geared hub motors are good torquey hill climbers at the expense of top speed, and I rarely have the desire or need to go faster than 40 kph.

*if you do this, be sure to buy from someone who took the controller from another radpower model with a geared hub motor. Given the very limited programming options on the display, I'm not sure a controller set for the magnet count etc. on a direct drive model would work for a geared hub.
 
Thanks a lot folks. Really useful stuff….

After reading your posts, I have decided to start the week buying the display and the controller (from Bolton Bikes btw). I have thought about the recommendation to buy a second hand one (thanks legsofbeer!), but in the end I have opted for a brand new 35a controller since I am almost certain that I will end up buying a new and (hopefully) more powerful motor. And I really like the idea of playing with the controller settings (as CCount …). What I may do is wait to mount the new controller and display before buying the motor. Everything will depend on the shipping times to Italy, which I hope will not exceed one month. If it takes longer, I might take the risk and get the motor right away…
Once the controller is here I will definitely try to mount it in the place where the original one mounts, so I will check the option of getting a plastic controller box from Amazon as Ccount did (thanks for the info!)….

Concerning the motor, I found this one from Electro Bike World:
https://electrobikeworld.com/products/48v-750w-bafang-geared-rear-hub-motor
It comes with a freewheel 7 speed multi gear, which I think is what I need (thanks cuekwe Jones!) and perhaps similar or the same to the one that Ccount got (right?). By the way, I´m very curious about hte derailleur project that Ccount mention to change gears while pedaling (please, let us know your progress there…). Your other project of the second 1000w hub motor in the front wheel (yes I read what you posted about it! )is definitely out of my league :) ...

Concerning removing the gear from the 750w motor I found this which I think might help…
https://www.amazon.com/gp/product/B...6b38aaad3783c760c5e2fc4660e86e&language=en_US

Have a great Monday guys
 
Concerning the motor, I found this one from Electro Bike World:
https://electrobikeworld.com/products/48v-750w-bafang-geared-rear-hub-motor
It comes with a freewheel 7 speed multi gear, which I think is what I need (thanks cuekwe Jones!) and perhaps similar or the same to the one that Ccount got (right?). By the way, I´m very curious about hte derailleur project that Ccount mention to change gears while pedaling (please, let us know your progress there…). Your other project of the second 1000w hub motor in the front wheel (yes I read what you posted about it! )is definitely out of my league :) ...

Concerning removing the gear from the 750w motor I found this which I think might help…
https://www.amazon.com/gp/product/B...6b38aaad3783c760c5e2fc4660e86e&language=en_US
If any 750W motor will work the RR1, it's probably the one you ordered from Electro Bike World (EBW) -- it is the freewheel type with a 175mm dropout and I believe has a motor cable/connector that is plug-and-play compatible with the upgraded motor controller from either Bolton or EBW. However, I don't know how you will ever get that 7-speed sprocket to fit between the rear dropouts on the RR1. For as I understand, RPB had to redesign (widen) the frame of the RadRunner Plus (RR+) in order to accommodate a 7-speed sprocket. Though I could be mistaken about this...

For what it's worth, I am in the process of trying to retrofit my RR1 with a narrower 3-speed sprocket -- the sprocket is in transit and I believe is scheduled for delivery today (although I am currently on holiday and will not get to this project any earlier than the forthcoming weekend). Once I verify that this sprocket will fit, I plan to order a derailleur, shifter, and cable.
 
Hi there cuekwe Jones, many thanks for raising the issue of the 7-speed sprocket. This has also crossed my mind. Perhaps CCount can confirm that it fits, as I think that he managed to put it there and line up the chain on the 3rd gear...
Otherwise, I have also found other seller with not cassette/freewheel attached to the motor, but I´m not sure about the compatibitliy of the connector with the controller, among other things....


In any case, please le me know about your progress of installing a derailleur, which probably I´ll end up doing.......thanks!
 
Hi there cuekwe Jones, many thanks for raising the issue of the 7-speed sprocket. This has also crossed my mind. Perhaps CCount can confirm that it fits, as I think that he managed to put it there and line up the chain on the 3rd gear...
Otherwise, I have also found other seller with not cassette/freewheel attached to the motor, but I´m not sure about the compatibitliy of the connector with the controller, among other things....


In any case, please le me know about your progress of installing a derailleur, which probably I´ll end up doing.......thanks!
I notice from this link that the motor is described as a "CASSETTA" which I believe may/will be incompatible with your stock single-speed freewheel sprocket. I am no expert on these matters, but I believe the difference between a "freewheel" and a "cassette" is important -- the two are not directly interchangeable.
Here is a good video that explains the difference:


Here is the source I plan to use (freewheel version without the sprocket for $199): https://eunorau-ebike.com/products/bafang-48v750w-rear-hub-motor-with-disc-brake-for-fat-bike?variant=364986400781&utm_medium=cpc&utm_source=google&utm_campaign=Google Shopping
If anyone knows a reason why this motor or source is a bad idea, please let me know...

As for the multi-speed sprocket that comes with your new motor, there is no principled reason why you must use it -- it will likely arrive uninstalled on the motor. So if you can first remove the stock single-speed freewheel from your RR1 -- using whatever removal method -- then you should be able to just screw the stock freewheel sprocket back onto the new motor. However, due to the difference in axle length, the stock sprocket may not align properly with your chain tensioner and/or chainring.
I've noticed, for example, that the stock motor on my my RR1 has a spacer cast directly onto the motor case which offsets the stock sprocket (I assume for purposes of alignment). However, I also notice from online photos that this spacer is absent on most/all of the upgraded 750W motors. If alignment is a problem for the stock single-speed sprocket on your new 750W motor, you may be able to solve this problem simply by installing an appropriately sized spacer.
 
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Hi there cuekwe Jones and many thanks for the link! I did not buy the motor yet (only the controller and display) so your tip and the link are very useful. If I understand you correctly, with the freewheel motor hub (no sprocket) that you put in your post, you just need to swap the motors and then extract the single-speed sprocket from the original motor and put it in the new 750w motor adding adequate spacers, as needed, right?
 
If I understand you correctly, with the freewheel motor hub (no sprocket) that you put in your post, you just need to swap the motors and then extract the single-speed sprocket from the original motor and put it in the new 750w motor adding adequate spacers, as needed, right?
Near as I can tell, yes (everything you said here seems to me correct). However since I have not yet performed a motor swap, I cannot say with any great certainty/confidence (beyond what I can see from photos, what I have read in other forum posts, etc.).

I actually own both a RadRunner 1 and a RadRunner Plus (the RR+ has a stock 7-speed freewheel sprocket). The RR+ is stored at my vacation home, where I am at this moment. Later today, or maybe tomorrow, I plan to take some photos and measurements from the motor area of this bike to verify any differences between it and the RR1. If I find anything especially interesting/useful, I will post those photos/measurements here. But to repeat, I have read -- somewhere??? -- that RPB had to modify the frame on the RR+ to accommodate the shiftable gears/sprocket. One thing I know for sure is that RPB added a shifter/derailleur cable mount welded to the rear part of the frame. I have not yet figured out how to replicate this on the RR1, but it does not strike me as insurmountable.

UPDATE: On the RR+, the horizontal distance from the outermost surface of the motor case to the innermost point on the rear dropout is ~2 inches (which is approximately the space filled by the 7-gear sprocket). Unlike the RR1, there is no "cast-in" offset spacer on this motor case, thus making more room for the 7-speed sprocket (I now suspect this is the case for all Rad bikes that have a 7-gear sprocket). It seems that RPB convinced Bafang to add this spacer to the RR1 -- a pity, though, that it's cast into the motor case itself and thus not removable.
More precisely, I believe the width of the offset spacer on the RR1 motor is ~1/2", thus leaving ~1 1/2" for the single-speed sprocket. Now, since this spacer is absent on the upgraded 750W motors (or anyhow all that I have seen so far), it might be possible to sneak a 7-gear sprocket into the available space on the RR1 using the new motor.
If correct, then I may try this instead of the 3-gear sprocket that I currently have on order (which was relatively inexpensive -- $16 USD).
 
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Concerning removing the gear from the 750w motor I found this which I think might help…
https://www.amazon.com/gp/product/B...6b38aaad3783c760c5e2fc4660e86e&language=en_US

These bits are necessary to remove the cover on the Baffang motor. I would advise a squirt of penetrating oil, and let it sit an hour or so, and use an impact wrench if you have one, to remove the security screws. You DO NOT want to strip them!!! However, you will still need to remove the large nut in order to remove the gear. This is where the punch and hammer or my idea of 90degree needle nose pliers come in.
Have a great Monday guys
 
As for the multi-speed sprocket that comes with your new motor, there is no principled reason why you must use it -- it will likely arrive uninstalled on the motor. So if you can first remove the stock single-speed freewheel from your RR1 -- using whatever removal method -- then you should be able to just screw the stock freewheel sprocket back onto the new motor. However, due to the difference in axle length, the stock sprocket may not align properly with your chain tensioner and/or chainring.
I've noticed, for example, that the stock motor on my my RR1 has a spacer cast directly onto the motor case which offsets the stock sprocket (I assume for purposes of alignment). However, I also notice from online photos that this spacer is absent on most/all of the upgraded 750W motors. If alignment is a problem for the stock single-speed sprocket on your new 750W motor, you may be able to solve this problem simply by installing an appropriately sized spacer.


The reason I chose to use the 7 gear part that came with my motor is for allignment. The single gear off of the original motor will not even come close to lining up. The gear set I used is identical to the one pictured in the far background of the photo above. I can think of no other way to align the chain with the front gear without using the 7 gear part (I don't know what it should be called) and selecting the gear which comes the closest to lining up (the 3rd for me). A bonus is that installing a derailleur will be that much easier, to allow gear shifting while pedaling. I have installed my selector on the handlebars, have run the cable, and will be installing the derailleur soon. I really think it will work with some tweaking!
 
I have installed my selector on the handlebars, have run the cable, and will be installing the derailleur soon. I really think it will work with some tweaking!
I am keen to hear how this turns out, and exactly which components you used. As mentioned, I have opted for a 3-gear sprocket for the time being (mainly because I am not yet prepared to drop close to $500 on a new motor, controller, and display -- my hope is that prices on these items might begin to drop soon as more aftermarket suppliers come online).
 
Morning Ccount and cewkwe Jones, thank you very much for sharing your experiences as well as opinions. I think I've made up my mind. I will buy the 750w Motor with the freewheel that EBW sells (not without suffering since 300 USD including international shipping hurts...). In any case, I will write to the company first to see if they have any tip to install it in the Rardrunner. I´ll keep you posted...

I´m also considering seriously to install the derailleur right away....not 100% sure though (need to read more about this....)

Enjoy Tuesday guys....
 
So i got this answer from EBW when I asked the about installing the 750w Motor in the Radrunner:

If the Radrunner has the same motor as the Radrover & Radmini then yes our "true" 750w motor will fit inside your existing motor case. Our motor comes with a 7sp gear freewheel but you can certainly remove your single speed gear and install it on our motor. You will need to get our gear spacer below to keep the chain line up with the front sprocket. Link to this is below, let us know if you have further questions.

https://electrobikeworld.com/products/gear-spacers-for-hub-motors

I´m not sure if the Radrunner has the same motor than the other two, but I would say yes. Perhaps somebody around can confirm....cheers
 
but you can certainly remove your single speed gear and install it on our motor.
Just to be clear, and to repeat, the RR1 appears to have a custom motor case (or housing) on the side of the rear sprocket -- it contains an offset spacer that I believe is absent on all other RPB bikes that come stock with a 7-speed rear sprocket, including the RR+. This spacer (I believe) is also absent on all of the replacement (or "upgraded") 750W Bafang motors. And so I further believe that trying to re-install your existing single-speed freewheel onto the new motor will not work (contrary to what EBW suggests here) -- it will screw on to the new motor but will likely be severely misaligned with the RR1's chain tensioner and front chain ring (unless you can somehow add a custom spacer, yet which I think will also not work because of the thread design for the freewheel).

Bottom line: If you replace the motor on the RR1 (the "guts") you will likely be forced to use the 7-speed sprocket stack supplied with the new EBW motor. This does not necessarily mean that you must also install a derailleur and shifter, however. Rather as some RR1 owners report, you just find a gear on the new 7-speed sprocket that properly aligns with the existing chain tensioner. But then this one gear -- whichever one it turns out to be -- becomes fixed and will serve as your new single-speed freewheel.

Hope I explained this clearly enough. But if not please request further clarification. Also, perhaps others will jump in here to correct me if I am mistaken about any of this.
 
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Thanks! Cristal clear. What you say is also consistent with what Ccount reports...
Also, my new 3-speed sprocket has arrived and I plan to tinker with it over the next couple of days. Since I do not yet have an upgraded motor, I am hoping (betting) that this sprocket will fit the RR1 even with the offset spacer. I believe it will because the new 3-speed sprocket is approximately the same overall width as the stock single-speed freewheel.

If it fits, then I plan to purchase a derailleur and shifter to see if I can give the RR1 at least 3 speeds, which I believe will still constitute a noticeable improvement over a single speed. The new sprocket is a 14-17-20t as compared with the stock 16t sprocket. If this works, I should see a small benefit on the low end (for climbing hills) and the high end (to help reduce so called "ghost pedaling" at higher speeds). If this doesn't work, not a big deal -- this new sprocket cost just $16 (including free shipping).

My long-term plan is to eventually perform the full RR1 makeover -- new motor, controller, display, and 7 shiftable gears. Since I cannot find either a 3-speed shifter or rear derailleur, I am going to purchase the 7-speed components, initially, and again hope that I can make them work with my 3-speed sprocket (I just need to limit the derailleur travel on the higher gears).

Also, for what it's worth, I have already installed a front suspension fork on my RR1, which I purchased directly from RPB for $150 USD -- this is the same suspension fork that RPB uses on the RR+. I mentioned my purchase to someone else in another forum, and they contacted RPB to order/purchase the same fork. However this person reported back that (for some reason??) RPB would not sell them this fork. Maybe they sold one to me only because I also own a RR+, but who knows??? At any rate, there is at least one other supplier of a similar fork -- Biketrix out of Canada, but for $250 USD (or anyhow the last time I checked).

But if you can get your hands on one, mounting the front disc brake to this fork required some minor modifications. But now knowing what's required, I could probably repeat this entire installation in about 30 minutes -- everything else fits perfectly. The one side effect is that since the new fork is about 1" longer than the stock rigid fork, the new fork raises the entire front end of the RR1 by about 1" -- only barely noticeable from an aesthetic standpoint. Yet I also had to shim-down the center kickstand by about 1/16" to account for the rise. Btw, the center kickstand may also present a problem when adding a rear derailleur to the RR1 -- I've been told by RPB that this is the reason they switched to a side kickstand on the RR+ -- the center kickstand interferes with the lower-hanging derailleur cage (as compared with the stock chain tensioner on the RR1). So, in short, if you add a 7-speed derailleur to your RR1, you may be forced to switch to side kickstand (although I suspect that some short-cage derailleurs may avoid this problem).
 
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Thanks! Cristal clear. What you say is also consistent with what Ccount reports...
I agree completely. I ordered some of those spacers, but never got around to trying them out. I am deep into my derailleur installation and gear shift project, so I am glad I chose the 7 gear option. However, I would think it may be possible to utilize those spacers to be able to re-use the original single gear?
 
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