EME / NWT R3.S Electrical Hub… Hit or Miss?

Background

I got into all this as a hobby. I am not a professional mechanic, and I am not an expert on motorcycle work. I am an autodidact and love learning new things, working with my hands, and challenging myself in many ways. I think of myself as capable and confident in my ability to add to my skills. Project Red was my first project, and it was always meant to be a full rebuild and modernization project. Along that journey, I learned a ton about the mono shock airhead BMWs. One thing that I tackled on that project was what to do about the electrics. I don’t hold to the purists out there who seem to think these bikes should be kept in factory form, especially when it comes to the original analog electrics. On that project, I used the EME / NWT R21 electrical hub and rewired the entire bike. It was a challenge and I ran into problems but was able to solve them.

Based on that, I opted to stay with the same approach on Project Blue. It’s been a couple years since I planned Project Red and in that time, a new version of the electrical hub was released. While I have a spare R21, I decided to go with the new version on Blue. This post is a bit of a rant that results from that decision.

The Promise of a Modern Electrical Hub

As a newcomer to this hobby, there is a lot to take in. Especially if, like me, you want to do as much of the work yourself as possible. Original BMW wiring is a rat’s nest of backtracked wires, proprietary connectors and relays, and inconsistencies in the various wiring diagrams available. This all works and is reliable in OEM form as long as that’s what you are happy with. Like everything on these bikes, its based 1960s and 1970s technology which is part of what gives these bikes their charm. Apart from a couple minor changes to the wiring design over the full production, the 1990s bikes are very similar to the 1970s versions.

Where you run into issues is if you want to modernize things. The charging system is limited and adding too many things can stretch the capabilities. LED lighting requires adaptations, and adding things like auxiliary lights, power options, etc. all add to the already confusing wiring. Switching over to a modern digital hub allows you to simplify the entire bike’s wiring. You can eliminate or reduce the number of relays, update to full LED lights and use more standard connectors. You can also get added electrical features to improve how lighting works, add circuit protections and other features. You also will know the full state of the whole bike when you finish. New wires, new connectors, new bulbs, all done and working. The EME / NWT hubs also work with OEM switchgear, allowing the updates to be more of a “stealth” upgrade.

The Strong Points

I’ll try to start with the positives. NWT, who manufactures the hub, offers very good personal support by phone and email. They will even create a custom wiring plan for your bike if you provide them with the exact inventory of parts you intend to use. NWT provides very simple diagrams for most configuration options you may have, covering the basic components found an any of these bikes. Once installed, they largely work as advertised. Once I worked the bugs out on Project Red, it became a solid and reliable bike with no electrical surprises.

NWT is a company built for motorcycle enthusiasts. They know their customers are working on bikes all weekend, so they work on the weekend as well, taking Monday and Tuesday off instead.

The R3.S is a pretty large upgrade from the R21. It has more onboard intelligence and configurability. the PCB is a clean design with all the connectors along the same edge. The provided harnesses use standard Molex connectors with 4.2mm and 3mm pitch. Very common and easy to work with. They are also labeled making them easy to keep straight.

Falling Short

As I write this, I have still not completed the install of my R3.S. The experience has been a larger challenge than the last project and I think it’s worth noting that it can quickly become frustrating. The R3 models have some glaring shortcomings, and I have a growing list of frustrations. Some relatively small, others continue to be more severe.

Construction

While the PCB is clean and clearly well thought out, the overall package leaves a bit to be desired. The board is not attached to anything within the enclosure. It’s just sandwiched in between the two halves. When it’s all together, it’s alright and things don’t move around, but it doesn’t inspire confidence.

The enclosure is 3D printed and it has a bit of a flimsy feel to it. A bit cheap. It’s also a pretty terrible design. With the cover on, you cannot access any of the switches that control the settings. If you swap out a component, change your plan, or simply made the wrong choice on a switch, you must open it up to check or change. That gets to the next problem. The enclosure is held together with two small wood screws, or something similar. They are simply torqued into the enclosure. If you are going to use 3D printing on a product like this, the better method is to use a heat-set thread insert and standard sized hardware to get the job done.

Then, there’s the real kicker. The hub needs to be mounted somewhere. Wherever that ends up being, you’ll need to figure out a plan. There are no provisions for hard-mounting. Only four places where you can find some options to use zip-ties or Velcro straps. And once you have it mounted, if you have blocked the back side of the enclosure, you have created yet another problem. The screws that hold the enclosure together are on the back. So, if you must open it up for anything, you need to unmount it.

I wish the PCB was designed with mounting screws in mind and the enclosure had been thought out a lot more. I would up designing my own case to solve for most of this. I’ll make the files available for download on my downloads page.

Pinout Thoughtfulness

While the PCB is put together well, there is room for improvement. The harnesses are setup around specific functional groups, for the most part. There are some annoying choices in where some things are connected. Consider the brake switch input. The vast preponderance of bikes out there will have a brake switch triggered by the right-hand brake lever. Most will also have a rear switch activated by the foot brake. From the R3.S point of view, a brake switch is an input and is pinned to the Input harness. This means you need to have a wire from the input harness routed with the switch harness to the right-hand controls.

There are also a few examples where wire adjacency should have been considered. Most installations will send two wires to the starter. It would make sense to have these on adjacent pins since they will route to the same place. Nope. You are really forced to make a minor rats nest to get wires neatly heading in the right directions together.

Size

It’s big. Considerably larger than the R21 and larger than other hubs out there. It does more, but I can see it being tough to find a home on some projects due to its size.

Quality Control

This has to be added here. I had everything wired up and not getting successful results. A lot of troubleshooting, rechecking of wiring plans, and ruling other things out, I found several of the connections on the Molex were either not working or only working part of the time. I had to unwire the bike and I wound up just making my own harnesses from scratch. This was a straightforward, but somewhat tedious process. Especially on something that should have been properly tested before shipping.

Documentation

This is probably my largest gripe. I know NWT makes products for a number of brands and I can’t speak to the general intellectual curiosity of the average Honda or Kawasaki builder. I can say that a fair number of BMW folks are quite detail oriented. There are a lot of highly analytical, engineering minded folks working on these bikes. NWT documentation is sufficient in that it shows how to install the hub in a number of the common setups. It includes variations on the different versions of parts a lot of us will be using. Sounds great, and it is a nice approach for the straightforward installs. If you have some bits that are not in one of the mixes they’ve covered, you are going to spend a good deal of time working it out. This is because all NWT documentation that I’ve seen is primarily graphical. It shows what wire goes where. That’s it.

What is missing is any effort to provide a technical explanation of what this does and what features are available. What voltages and amps are available or expected on any wire? How does the type 2 switchback work for LED running lights or HALOs? What is the Master Light Control? Which way is “On” for the unlabeled dip switches, especially the one that is not oriented the way it’s depicted in the graphics? For the instruments, why not label the PIN numbers for all the diagrams? It is a bit maddening.

All this can be addressed if you email them, then call them, then email more details. They will even make a custom diagram for your project if you send them the inventory of components on your bike. That’s great, but it all takes time. Mine and theirs. They would be well served by hiring a technical writer to create more detailed documentation. Motogadget does a far better job of this.

My Ruling: It’s not quite there.

As I am continuing to work my way through my build, I am landing on this is a miss. It’s a great concept and I think the core of it is 95% there. All my frustrations with it are things I would expecting a prototype, not a several hundred-dollar retail product. It feels like they got the product working on all core features then rushed it to the sales floor. Even taking the complexity of my project into account, there are still too many missed opportunities.

Should you buy one?

Only if you are doing a basic project with only limited creative electrical additions or if you have a lot of patience to work through some frustrations.

My Final Design

My redesigned enclosure through several iterations. It lets the PCB snap into place and is secure when the cover is on. It also allows me to bolt it to the mounting plate and remove the cover without unmounting.

Edits

2026.03.13: minor corrections made for typos. Added link to download Enclosure.