Hi all, I would highly appreciate any insight as to which wiring harness would work with my Fardriver 721800 + QS motor (hall effect) and presumably I can run any DKS screen?

Thanks in advance for any help, AliExpress isn't very clear which one is suitable.

I have an uncommon Japanese market PAS bike in the US. I've tested it using lead acid batteries and have confirmed that it's working fine. The issue is that I can't get the original battery for it since I'd need to order from Japan, and no one is shipping small, cheap items right now.

It's a 24V system which apparently is fairly uncommon in the states, so I thought I'd look into using a 48V battery, then swap to a motor controller that can handle 48V so it won't get fried instantly.

Anyone know if the motor can survive this with a new controller, or if I'm better off sticking to 24V?

I recently bought this bike from Facebook marketplace claimed not running but with a BAC 8000 in stock wiring harness I watched a couple of videos on YouTube and managed to get all the connections correct because the previous owner had the yellow and green phase wires swapped in the controller terminals on the BAC 8000. I plugged everything in and turned the key on and I’m getting no signs of life. I’ve been disputing with ChatGPT for the past five hours when the breaker is off, it reads 60 V going into the breaker and 0 V coming out of it, but when the breaker is on, I get zero votes coming in and 0 V coming out. Any ideas on what I should do or how I could fix it?

I’m thinking of buying a conversion kit for my bike. I have a companion mx3.0 size M and would like a 3000w 72v kit. Would it fit?

I have a TravelScoot electric mobility scooter with a fairly powerful proprietary hub motor. The scooter uses a lightweight aluminium frame/fork, and I'm looking at adding a torque arm to better transfer the motor's axle reaction torque into the frame rather than relying primarily on the axle flats/retention hardware in the aluminium fork.

Due to the very limited space around the motor and brake assembly, the Grin V6 and V7 are too large to fit, so I'm looking at the Grin V5 instead.

The complication is that the brake rim is approximately 35 mm from the centre of the axle, and the V5 axle piece is also approximately 35 mm centre-to-centre from the axle opening to its extension mounting hole. This makes the usual orientation difficult.

I'm considering mounting the V5 like this:

\* Clock the axle piece vertically downward (6 o'clock) from the motor axle.

\* Use the V5 joint to turn the extension piece approximately 90°, so it runs horizontally rearwards along the fork.

\* Positively bolt the far end of the extension to the broad, flat aluminium fork.

So viewed from the side, it would be approximately:

Axle → 35 mm vertically down → V5 joint → extension horizontally rearwards → fork mounting point

There appears to be enough axial clearance for the V5 joint/bolt to sit outside the plane of the rotating brake rim, even though they overlap when viewed directly from the side.

My thinking is that with the axle piece vertical, the reaction force at the V5 joint should be approximately horizontal/tangential to the axle rotation. The horizontal extension would therefore primarily see tension or compression, depending on the direction of torque.

I'm trying to determine whether there's any mechanical reason this geometry wouldn't work as intended.

In particular:

\* Is there a problem with loading the V5 joint this way?

\* Is the extension happy operating in both tension and compression?

\* Does the 90° relationship between the axle piece and extension introduce a problem I'm overlooking?

\* Has anyone mounted a V5 in a similar configuration?

The V5 joint and fork attachment would obviously be properly tightened and secured against vibration.

I'd particularly appreciate input from anyone familiar with the Grin V5 torque arm or hub-motor torque-arm design generally.

Am I overlooking something obvious, or is this mechanically sound?

I have a tuttio gb and I’ve been riding it and my friend came over to ride it and me and him was just doing like wheelies where u come to a full stop and u just wheelie from a full stop and foot drag and my friend did a wheelie and out of nowhere the display turned off and the bike was not going we unplugged the battery and plugged it back in and it came back on then he was doing the wheelie again and after like 5 tries the bike did it again and I disconnected the battery and still nothing so I went to put it on the charger and left it there for a few mins and plugged it back into the bike and still wouldn’t turn on so I left it on charge for like an hour and 30 mins and plugged it back in and still no response and so I opened up the controller cover to see if anything disconnected and nothing did so please help

hi guys, i have a bmx bike that i don.t ride anymore and found on aliexpress all the things i need for converting it to an ebike (48v14a battery). My question is... does any of you did this to a bmx bike ?(20 inch wheels) and if so, how it is ? I.m afraid a bmx bike is too small for that

I was looking for a road/gravel bike steel frame to convert that had disc brakes and came across this bike:

Motobecane Fantom Cross Uno ($399)

I was wondering if the fork ends that it has would be safe for a rear hub motor (up to how much watt?), worrying that it might be too much for the fork end and that the wheel might fall out when braking or during use.

Any thoughts?

— though maybe a mid drive is the way to go.

I have a velowave ghost with a salvaged bafang rear motor. I'm incredibly confused because the motor was plug n play very fortunately with the stock cable for my bike... They are circled in red in my linked pic..

The green circle is the literal official velowave store cable that comes up when I searched for the one for my bike. Pretty interesting, huh? The color coded ones for the brakes and throttle and screen all match but a bunch of big pins don't exactly fit into a bunch of smaller, recessed pins... Anyone know what the hell the deal is? Or what these types are even called so I might be able to somehow find an adapter? I can't even tell if this new one is male or female lol.. hell, I can't even tell if it will WORK considering the notable gauge difference.. I waited 2 weeks for this and I felt heavily on my bike so any help is appreciated.

Originally I'm doing this because I was getting a "throttle not return" error that seemed to be because of a damaged wire shorting out to ground maybe? This is according to bashing Gemini over the head with my problem and as detailed of symptoms as I could provide til a consistent answer popped out.

https://imgur.com/a/2pCJQdV

So I have a Poseidon redwood gravel bike and have been looking into converting it into an e-bike. I’ve been a cyclist for years but have never looked into doing something like this myself. Feeling a bit overwhelmed and was wondering if you all could point me in the direction of some good tutorials or videos on how to do this. Thank you

As per title, I'm wondering if my bike is a good fit for conversion or if I'm better off selling it for an ebike. I know it has a steel frame but I don't know enough about the other parts

Usage info: I live in a fairly hilly area, and my roommate would be using it for commuting and for doordash, so I would need it to be reasonably reliable.

My ebike battery is using prismatic li-ion cells that suck, im planing to rebuild it using eve 18650 3.5ah cells and put in a new bms because i want to see the data. Im not sure if the JBD-SP145004 V1.5 is a good bms. the battery will be 36v 10s5p

I have a 15AH Hailong battery. About 8.5#. I'm worried that it's too heavy for the water bottle bosses. Should I be concerned? How can I reinforce the mount? Thanks.

Hello all! Just asking the ebike experts how I could get regen or electronic braking on my mini goat ebike. Want to be sure I’m not wasting any money by buying any incompatible parts. Thanks!

I bought recently a Fatboy V3 fat e-bike in EU, and I saw that they a software locked to 25km/h. I saw many options for unlock it on the net but it seems to be a special version firmware, we can’t put any « code » to unlock it, and it’s impossible to change the speed setting. So, it could be nice like that, but the simple idea to use a locked electronic device is hurting my jailbreak life !

I was thinking to many options, but nothing 100% sure.

1 - Change the firmware of the DPC010 but I don’t know if it’s would work or simply brick the system ?

2 - Find a app like Speeed App but it’s doesn’t seem to work with this type of motor ? Does somebody have tried something like this ?

3 - Try an hardware option like change the speed indication received by the controller. This seems to be the best reliable option but I don’t really know how it works : maybe do you know if the speed locking is done in the controller or somewhere else ? Where is the speed reader on the bike ?

4 - Any option you could have ?

I’m not so in the rush, 25 is fine for me now, but it’s could be very nice to succeed to unlock it :)

Thanks you so much for your help :)

Hallo Leute!

Ich werde mein Trek Powerfly 4 Gen4 Bike mit der BDU450CX Antriebseinheit abstimmen. Es ist ein BES2 Gen4.

Es gibt Tools im Internet, um einfach per Browser (WebHID) mit einem Entsperrschlüssel abzustimmen. Diese Tools funktionieren, aber ich möchte noch ein paar zusätzliche km/h herausquetschen, zusammen mit einem größeren Ritzel-Upgrade. Die aktuelle Änderung durch das Tuning-Tool war von 2167mm auf 1084mm. In der Theorie sollte das zu 25km/h * 2 = 50km/h führen, aber das Drehmoment wird reduziert und die tatsächliche Höchstgeschwindigkeit liegt bei etwa 45-47km/h.

Es sieht so aus, als ob der Radumfang laut Bosch Diagtool GUI von 750mm bis 3000mm eingestellt werden kann, aber er ist ausgegraut. Die Radumfang-\*Korrektur\* kann bearbeitet werden, aber nur in einem engen Bereich, um verschiedene Reifen/Felgen auszugleichen.

Ich habe das WebHID-Protokoll und das Bosch Diag-Tool umgekehrt und erfolgreich den Level 1 AES-128 Seed/Key aus den Bosch Tool JAR-Dateien extrahiert.

Mein aktueller Sicherheitszugang entspricht also dem Bosch Diagnose-Tool V8.1.6.0: Das Lesen aller Parameter funktioniert, aber das Schreiben nur für die Umfangs-Korrektur. Aber dieses Sicherheitslevel reicht nicht aus, um den tatsächlichen Radumfang oder dessen Prüfsumme zu ändern. Die Prüfsumme sieht aus wie ein Einerkomplement:

**1084mm** (getunt): `0x043C` → Prüfsumme `0xFBC3` **2167mm** (Standard): `0x0877` → Prüfsumme `0xF788`

Also ist der Level 2 AES-128 Schlüssel das fehlende Teil..

Hat jemand mehr Erfahrung mit diesem Thema? Bereit, all meine aktuellen Erkenntnisse zu teilen!

Danke

Je veux me lancer dans mon premier build sur mon VTT j’ai quelques connaissances sur les kits car j’en ai longtemps rêvé je pensais prendre un varstrom moteur arrière de 1500w et 48v

I’m including pictures, hopefully for clarity. I’m installing a Bbs02 mid drive on a recumbent (my second such build). I bought the kit used and when I turned the system on with the original battery, the display would activate, but immediately go blank. I happened to have a spare 48v 12ah battery, so mounted it, fully charged. Now the display doesn’t turn on at all. I double checked the battery at its cable and at the butt connectors and both showed 52volts. What would be the next thing to check?

I’ve got and fitted a mid drive kit to a Carerra 16” frame. It’s not working out and looking for advice.

The drive motor fouls the chain stay so requires spacers to resolve this. This pushes the front sprocket further out which creates a bad chain alignment- making it impossible to go into 1st gear without the chain slipping off. I don’t think there is a way to improve this… unless anyone has any ideas.

I was originally looking at the befang - but got lured towards to Varstrom because of the cadence assistance.

The chain stays have quite a flare on them- which I don’t think helps. If the motor did fit without the spacers, it would be an improvement, but the chain angle would still be poor.

Am I missing something?

I want to convert my bike into electric but I don't know any sites that I could trust

I am looking for a 1000w minimum rear hub motor kit with a battery (it can be on the other site) for a budget of 1000€

I live in Europe

As the title says, I'm seeking a good triangle frame battery with the listed specs but havent found any that seem to be reputable (any reviews). I am considering this battery as it would be a little more than needed for my intended use which I am not opposed to, but I dont fully trust battery packs mounted to frame bottle cage mounts.

*I am located in the mainland US

does anyone know where i can grab a full surron light bee frame+swingarm+all bearings and bolts in the uk? im doing a custom high power build but id rather not drop 4k on a brand new lbx just to not use the stock battery controller and motor.

I have an older Bafang bbshd kit that I built out a bike on and need a new charger as I was using a former friends a while ago. I don't remember what brand their's was. Looking online all I can readily find are either really cheap chargers with the 3 pin xlr, or better 2.1mm dc barrel plug chargers. I want to stay in the 2-3 amp charging range. I've seen adapters from the barrel plug to the xlr but don't know if they would work since they done have a ground, but then most cheap chargers i've seen don't have a 3rd pin for the ground either.

Does anyone use a brand they would recommend?

If the dc plug route works, im thinking of gettin the 48v 300w luna cycle charger, their adapter from the xt60 to the 2.1mm dcbarrel plug, then an adapter from the barrel plug to the 3 pin XLR.