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    Luna Fixed Stealth Bike

    Click image for larger version  Name:	Skype_Picture_2020_08_18T08_12_19_516Z.jpeg Views:	54 Size:	279.7 KB ID:	112183

    Warning, would should never shift under load, you can pedal while shifting but you need to avoid putting any pressure on the pedals! It's the same for all IGH hubs (ebikes or non-ebikes). Shifting under load will likely result in a misshift, permanent clanking noise or simply a broken gear.

    Stealth FIXED bike initial setup video

    Support notes: If you have a wobbling crank arm on the right side, tighten the right crank arm bolt and then tighten the left crank arm bolt too.. they are linked together. Once both bolts are tight the right crank should be tight

    Frequently asked questions

    I want to use a Luna charger, how?

    By default the Luna chargers use XT60 connectors, specifically XT60 male to plug into an xt60 female battery. This can be changed over to barrel either using our solderless barrel here or buying a plug and play adapter. Here is an example of a compatible adapter.

    Do not charge this battery at more than 3amps, it's a small battery pack and charging it any faster can result in poor cycle life.
    Do not use any other charger than a 36V Li-ion charger, once fully charged the battery should be at 42V (or close to this number, not over it)

    Belt Removal:

    But first you need to remove that shifter box (aka click box), put it on 2nd gear and loosen the rear nut at the back of the shifter box

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    You may need to loosen up the tensioner just a little, it possible that yours is already at the maximum forward position in that case just loosen up the axles nut.

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    Now that the axle is loose and at the most forward position, please watch this video to remove the belt.

    CS note: We have been in contact with Gates and removing the CDX Belt like this is fine.

    Adjusting the belt tension:

    Gates carbon drives has an app (android and IOS) to tune the belt to the right tension (on this bike best is 45-60hz). Just need a quiet place to do the tension test and need to test at multiple spots. But since this is a low power bike you can lower the tension to 30hz no problem there.

    Just watch these 2 videos:

    If you need to adjust the shifting after re-installing everything , please watch this video:


    If you pedal the bike without any motor assist you will hear a clicking noise from the motor, this is the sound of the clutch that disconnects the motor from the crank arms.

    This video was shot inside to it might sound a lot noisier then what you would hear on road, it's really quiet in real life!

    Adding fenders:  p3kAV2BuiwljJKNB7DB0mNNnANWn_4U_VnK5oUMkTVC33GWgwk  LaIQmvkcQM3-UsizLcVllaU_Ib8engryVStckjsJR7ZtX-Op18MkZcID6kg4c-B4eUFdbNYqY_x87Lp3kmCaT72TD49bU5kiaMGJ8aFVpxHykqcp  uuKA_YNYhMqrkbRBDfNoB7ICeRTrbjvyFhK9yi1skaGMr5NAj9  fZk9tqJgI0K80PVctySjXI7VCiX3XhfqTqLRi6KQQ0iRSqqmqc  HfjCNPllwvUNmCNYe6B2541EgkTSBz4EhqH9Me-930z0jWDlJ5HO-2gaejSwQlZxFtAv57x-xgiX7M_BwMiSQDATsMRqOV1Dae1rxn9bB-x-vysGezs_rHa-tJL9xrjqdOLm_eiGVoFvKXi4ZkYcoIPjFsbDmG8yoeXPF0_RFt  mWZbaH9QDx1fdPGscw9h8ryefSFzUPVsFYIgXlStwaKHkraUaH  ywU0lIMlMtEcdh1m0M-aqtjZC1TECWiHXJ61qBUnafzQeX0a3TPaT9dDHMkl9hU_3hJw0  e3wJ3QQhTw3YnXO4z0NR3i_p_z6ORL0afavjxVEnBYEfvs_KGu  OuRArMM_kze5tavhvkctne0_lw77_sjT77tmG1rnlPgTORQm6m  ctlFWzH0rh2rpG4QdxtKcwxTqQm6Q=w1907-h1431-no

    (with thanks to reddit user /u/bourbonben)

    Planet Bike Full bike fenders - 700c x 45mm

    Had to trim the front arms, and cut the mounting tab off the back. I used a zip tie for now, will secure it direct to the brake bridge when I eventually have the back wheel off.

    The "accessory" threaded holes on the rear of the frame are M6X1.0mm

    Considerations for adding second battery for more range

    Generally speaking this is not advisable. It would require extensive modifications and could compromise the battery. Please note that Luna can not take responsibility for the consequences if you break your bike or battery. There are a few separate proposals, we will discuss each below.

    Manually switching batteries: Physically unplugging battery 1 from the controller, then plugging battery 2 into the controller. This would be the most straightforward, and eliminates a lot of potential danger in doing the other methods incorrectly. As long as the second battery is a normal 36v nominal battery that should be fine.

    Alternately, this might work to switch it If you do use this, take care to switch it when the bike is not using ANY power. That is a relay and not rated up to 42V so take it from me that the relay wont last a few days if you start doing this. Always switch while the display is OFF. Here is a very nice well written post on Reddit by Tim a Luna Fixed Owner that added a secondary battery using that relay, just click here to be redirected.

    Parallel wiring: The idea here being that you would put another battery in parallel. Generally this is strongly discouraged on bms protected packs unless you are unplugging them from eachother when charging, and are making sure both batteries are identical, and both batteries are same voltage at time of connecting them. Given that this would be difficult to meet these requirements there is another way you might go by using a diode to block current from flowing back into the other battery. This page goes over that in more detail. For a working example of this idea in practice, see this page.

    Theoretically you could use Luna remote switches on each battery in that parallel circuit, and switch back and forth by turning the one battery off and then turning the other battery on. This would not be advisable due to the possibility of accidentally not turning the other battery off, which would lead to a massive influx of power which could cause a fire. It might be possible to modify a couple remotes to use the same button with a circuit to control making sure that one remote is always off before another one is turned on, but this is outside the scope of what we can advise on.

    Charging integrated battery via the charge port: This is not recommended for multiple reasons. Primarily because any second battery you want to wire up will have a discharge rate ten times higher than the safe charge rate on the charge port. This will burn out the charge port instantly and is also likely to damage the integrated battery on the bike. The port expects something like 2-3A, and another battery can put out 20-30A, maybe higher. Not to mention that at some point the external battery will want to draw current from the internal battery and the charge port is not made to feed anycurrent in reverse and will likely result in a dead BMS.

    Additionally, on many BMS-protected batteries the charge port is how the battery bms is reset if something trips it. So if you are charging the original battery while in use, if something like a short happens in a cell, (which normally the BMS would protect against by shutting down the battery) you may be forcing it to reset despite it not being safe to do so. Or at least making it so you have to disconnect from both the short and the charging source before it will reset.

    In theory you could limit the current of the discharge on the secondary pack using some custom circuitry, so when you plug into the charge port it is not charging it at some massively high rate of current. For example something like this, which can also do CC/CV charging, an important safety consideration. However, you may still be resetting the BMS on the original battery whenever you are charging it. Do so at your own risk.

    Error 21 on the dashboard or erratic speed reading and odometer reading resulting in motor cut-outs? Motor cutting out randomly while riding?

    Check your magnet and sensor aligment. The sensor can swivel if it gets hit so make sure it's like this:

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    Make sure the speedo sensor is aligned properly or you will experience erratic speed reading and motor cut-outs.

    Watch the next video, it shows you how the speed sensor angle can affect the speedo meter reading (watch carefully the blue circle meter on the display)

    Loosing torque assist under lower assist levels

    Try to loosen the belt a little, in some situations this issue was resolved by just lowring the tension a little. Start with 10hz less and test again.

    Crank arms or spindle loose?

    The FIXED has a very different crank arm to spindle attachment compared to a regular bike

    The spindle is a 2 piece unit and it's the left super long crank arm bolt that holds the 2 parts together so if the left crank arm bolt is not really tight the cranks arms can have some play in them. If you ride like this for a while it's possible to ruin the spindle. See attached this is a little simple drawing I did to explain how it's set up inside the motor

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    So start with tightening the left crank arm right good. 40-45nm it's normal after the first few rides to have to re-tighten them again.

    Removing the motor

    1st remove the cranks arm bolt and them the crank arm using a standard crank extractor
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    2) Remove the non drive side crank bolt. Its really long, holds the non drive side crank arm on, and threads into the drive tube. Use a standard crank puller to remove crank. pull on drive side crank arm. it will just pull out by hand, attached to a long, splined, drive tube.
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    CS NOTES: If the axle wont come out of the right side like the picture up, just insert a screwdriver (or a metal bar if it fits) in the LEFT (Non-drive side) crank arm bolt hole (about 2.5 inch long) and tap it in till the axle gets out on the right side.

    3rd to remove the front belt ring, you will need to start by prying out the rubber seal in the center of the ring:

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    4th using standard threaded bb tool, (BB-22) turn the splined nut clockwise to remove it, it's reverse thread so it turns the opposite of normal threads.

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    Tip: if you don't have an impact gun, you will have to lock the sprocket in place to be able to loosen up the lock nut... So put back the belt over it and lock the rear brakes (Velcro strap on it) and then turn the lock ring clockwise. When you put it back turn counter clockwise and use 30-35ft-lb or force.

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    5th remove the 6 phillips bolts on drive side, and remove the cover and trim ring.

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    6th loosen the 2 set screws on the top of the motor, they are 3mm hex.

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    7th the motor comes out through non drive side, so push it through slowly about 3/4 of the way by wiggling it as you go, unplug the 2 main connectors going to the motor
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    Step 7 video

    8th, once unplugged, pull the motor out of the frame,There is a metal plate the 2x 3mm bolts press onto. It just fits into a recess on the motor. Make sure to put it in a safe place so it isn't lost. That is the keyway to lock the motor in place so it wont rotate under power.Click image for larger version  Name:	IMG_1897.jpeg Views:	0 Size:	2.14 MB ID:	102245

    Battery and controller removal

    You can access the charge wire going into seat tube by just pushing the motor out halfway. It has a tiny XT30 connector on it, hopefully it just got unplugged if you are opening it for that reason.

    Once you got the motor out the battery and controller will want to slide out of the bike down tube as they are held by the motor case.

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    Then is a matter of sliding the PVC white tube out and unplugging the yellow XT60 connector from the battery to the controller.Click image for larger version  Name:	IMG_2161.JPG Views:	499 Size:	2.88 MB ID:	100003
    Last edited by Sebz; 09-28-2021, 12:15 PM.

    I'm curious about Shimano's new e-bike IGHs. The SG-C7000-5 is a 5 speed with a 263% range and first gear 1:1 (aiming at a 20 mph max, IIUC) and the SG-7001-8 is an 8 speed 307% with 1:1 5th gear.
    They're part of Shimano's Steps system; would it be a useful upgrade for the Stealth? I deal with hills and could be persuaded to beta test one... :-)


    • Retrorockit
      Retrorockit commented
      Editing a comment
      The 5 speed is new and was offered in Japan first, and is just now showing up on OEM bikes in Europe. It seems to be intended for the 350W 20mph world E bike market. The 1:1 first gear means it can work on small wheel folding bikes. Whether it will be offered for the 750W US market remains to be seen. It supports Di2 electronic shifting also. So maybe an automatic transmission ( they did this with a 4 speed IGH years ago).

    Can anyone confirm the sizes of the threaded holes on the seat stays above the axle? Mine appear to be different left - right. Unfortunately Luna support wasn't much help.

    EDIT - M6x1.00 - cleaned the holes out really well, then a little oil on the screws and it worked out just fine. Probably just paint/assembly crud in there.
    Last edited by purplegorilla23; 08-06-2019, 04:05 PM. Reason: Solved - M6x1.00


      Curious about replacing the batteries when they wear out, my commute is about 20 miles each way, so would charge/ discharge the bike about 300 times a year. This would be less than three years with a typical battery life? Then what’s entailed it remove/replace the cells? Would I have to pull the motor to gain access to the cells?


        MinnRider While I hate to have to say 'it depends', that would be the most accurate answer. The number of cycles you get is highly dependent upon how the battery is treated.

        See this page for a detailed rundown:

        See this page for supporting information


        • MinnRider
          MinnRider commented
          Editing a comment
          Thanks, the info on care and feeding of the batteries for maximum life is helpful. Still interested in the implied part of the question, though, once they do wear out, how difficult is it to replace them? With an external pack, it's pretty obvious and easy. Since these are in the downtube, how will I pull/replace them? I'd guess by pulling the motor and sliding them out individually, but perhaps there is an access opening on the downtube? Thanks.

        • paxtana
          paxtana commented
          Editing a comment
          You need to remove the motor and the entire thing slides out from there

        Regarding motor removal, I get to 4th and the chainring and all just spin with the BB and tool, clockwise. How do I turn just the splined nut? Not the first time I’m confused.


        • Jasdidit
          Jasdidit commented
          Editing a comment
          The picture shows how I did it. The threads are reverse, so I just used a 1/2" cordless impact driver in reverse to bbbbrrrraaaack, spin it right off. I tried using a ratchet, but that was just futile. It might be possible to use a rod through a hole in the chain ring to keep it from moving while the nut is loosened, but I had the 1/2" driver and decided to use that to prevent damaging the sprocket.

        bikedog good question. I don't have the answer but you could ask Joel, he's the agent that took those nice pics for us. He answers phones so if you give us a call and leave a message for Joel he should call you back within a business day.



        • bikedog
          bikedog commented
          Editing a comment
          Thank you. I spoke with Joel yesterday, a veritable font of wisdom he is. The impact wrench did not work for me, however, during our conversation he came up with put the rear wheel and belt back on and use the disc brake to immobilize the chain ring. Worked peachy keen swell. Joel opined that might be the factory method.

        Hi -- I'm interested in upgrading the Carbon Gates Belt Drive group set on the stealth -- it ships with 22T rear and 55T front, and I think the belt is 120T? I'd like to get more power from each rotation / go faster, but am curious what rear cog/front cog would work to these ends. The LBS says if I replace either the front or the rear, I need a longer belt. Ideally, I'd like to keep the 120T belt and simply upgrade either the rear or the front cog...from my understanding, either making the rear smaller (presumably less teeth?) or the front larger (more teeth) would be way to go. I basically want the 3 gears to mean more (right now, I tend to just stick in the third gear because pedaling in 1 or 2 doesn't feel like it gives me enough power). Thanks for your help.


        • ncmired
          ncmired commented
          Editing a comment
          Gates provides a few belt / sprocket calculators here: (smartphone and a Microsoft Excel spreadsheet).

          I experimented with the spreadsheet - given your current values I could not come up with a sprocket combination that retained your current belt AND maintained your presumed, current 444.6 center distance (changing both front and rear sprockets).

          A few problems - the smallest Gates rear sprocket that will fit the 3-speed hub is a 21 - not far from your current one. you do have some wiggle range with the front sprocket IF you're willing to change the belt.

          Be prepared for some sticker shock when purchasing the parts, as Gates has an exclusive. A 63 tooth front to a 21 rear, using a 125 belt might work (450.6), and help a little with the already too short belt issue (but, $$$).

          I'm sticking with chains ...
          Last edited by ncmired; 09-30-2019, 02:50 PM.

        • D1NY
          D1NY commented
          Editing a comment
          timmyd Was wondering if you ended up doing this? I'm thinking of doing the same.

        • timmyd
          timmyd commented
          Editing a comment
          D1NY - I ended up doing the upgrade, it's working really well so far. Details are here:

        Hey, Looking into purchasing one of these bikes. What is the recommendation for cold weather riding and storage? I intend to ride 10ish miles a day throughout winter and I have an un-heated garage. Will I be needing to bring my bike in to charge?

        Our temperatures average lows of 16F sometimes dropping much lower. I assume this might not be a good fit since its a built in battery, unless I want to bring my bike in every night.


        What size is the seat post? 27.2mm?


        • Sebz
          Sebz commented
          Editing a comment
          it's on the listing : Selle Royal saddle with 30.7mm seat tube

        The display on my Fixed Stealth is on the fritz. It seems like a loose connection on the LCD. Sometimes it works; other times the screen is all white. In this state I can still change the PAS level and turn the bike on and off, but I can't see any information on the display.

        Thus I ordered a replacement 500c. Unfortunately the cable coming out of my replacement display has a female end, while the one that came with the bike has a male end. Needless to say the cable display coming from the bike has a female end. Is there an easy way to connect the 2 female connectors to use my new display, or do I have to change the wiring harness?


          The 500c is not built for that system, it is incompatible. Unlike our bikes custom built to order this does not use BBSHD/BBS02 and as such cannot made use of that product ecosystem. You should email support to see if we can source you a replacement stock display.


            Thanks for the guides! Is it possible to power / control DC lights from the built in power systems? I couldn't find an obvious place to get switched DC power. Was looking at something like the Light & Motion Nip and Tuck system.


              Not easily, since all the wires are internally routed. You would be better off with a wireless light on a bike like this.


                Hi, I want to buy one of these while I am on holiday in the states and bring it back on the plane with me. How easy is it to remove the 18650 cells and am I correct in saying there are 20 of them ?


                • paxtana
                  paxtana commented
                  Editing a comment
                  It is illegal to bring that battery on any passenger aircraft, per international regulations. Does not matter if it is in the bike or not.

                  To remove the battery, remove the motor, then the battery slides out the bottom.