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Discussion Starter · #1 ·
Someone recently asked this on the Grom group on Facebook, and I posted this reply, so I figured I'd post in here as well in case anyone searches. Forums tend to get indexed by Google much better than Facebook posts do, and I wish I would have been able to find this information when I was shopping around and learning about what the different products for tuning were.
I know there are a lot of you who already know this information, but for total newbs like we all were at one point, all of it is new... so please don't hate.

GROM-Specific Part Numbers for DynoJet Products

Power Commander V (PCV) - #16-049

Wide Band 2 Module (WB2) - #15-7023

Common Abbreviations for Dynojet Products

PCV - This stands for "Power Commander V," which is the ECU-piggyback product from Dynojet that's used for making adjustments to the input/output of the bike's ECU, effectively tuning the bike. This abbreviation can be misleading to people who are familiar with engines, as PCV typically stands for "Positive Crankcase Ventilation."

WB2 - This stands for Wide Band 2, which is a product from DynoJet used for monitoring air fuel ratio via a wideband gauge. This product can be used in conjunction with a PCV or as a stand alone unit, as described below. Sometimes you will see the abbreviation "WBC2," which is an incorrect mix of the abbreviations "WBC" and "WB2."

WBC - Wideband Commander. This is a product from Dynojet that was essentially made obsolete by the Wide Band 2 product, which replaced it.

Autotune - I haven't seen an abbreviation for this product, but Autotune is another product from DynoJet designed to be used in conjunction with the PCV for automatically tuning maps on the PCV via input from sensors and a wideband O2 gauge, which must be installed as a part of the Autotune module install. This is described in greater detail below.

Links to Dynojet Product Pages


WB2 -

Autotune vs Wide Band 2

Autotune is a product that interfaces with the Power Commander V and allows the Power Commander V to tune the bike as you ride it. It includes a wideband O2 sensor and a bung that must be welded in to your exhaust. Autotune is meant to be used in conjunction with the Power Commander V and can not be used on its own.

Wide Band 2 is another product from Dynojet that can either be used as a stand-alone unit or in conjunction with the Power Commander V for auto tuning. A lot of people abbreviate this "WBC2" - which is wrong. The "Wideband Commander" product (WBC) was replaced by the Wide Band 2 product (WB2). These products are NOT the same thing, and "Wide Band 2" and "wideband O2 sensor" are not interchangeable terms. Wide Band 2 is a specific product by Dynojet, and a wideband O2 sensor is just a sensor that multiple companies make. The WB2 product, like Autotune, comes with a wideband O2 sensor, and a bung that must be welded in to your exhaust.

Unlike Autotune, Wide Band 2 can be used by itself, without the Power Commander V if all you want to do is read your air fuel ratio via a gauge. The unit supports output to an analog or digital wideband O2 gauge, and output to a data logger (first or third party). If you don't use it in conjunction with the PCV, it has leads that you can hook up to the bike to provide the WB2 with information about throttle position and RPMs, which can be used for logging. If you use it with the PCV, you don't have to hook these leads up, because it will pull that information from the PCV via the CAN BUS cable that connects the two units.

Wide Band 2 can be used in conjunction with the Power Commander V for auto tuning, and would function as a full replacement for the Autotune module. If you have a PCV and a WB2, there's no reason to purchase the Autotune product. WB2 provides some features that the Autotune does not - including output to an analog or digital gauge (as mentioned earlier), and a narrow band O2 sensor output, so you don't have to use the factory narrow band O2 sensor that comes with the bike. This allows the WB2 in conjunction with the PCV to fool O2 sensor readings to the Grom ECU and allows the system as a whole to enrich the fuel map in the 0-80% throttle range (closed loop range), where the PCV itself can not otherwise make adjustment.

All of that being said, if you want to auto tune on the Grom, and you want to go with the Dynojet products, Power Commander V and Wide Band 2 are the way to go. There's basically no reason to go with the Autotune module sans to save a few bucks... but the extra features that come with WB2 make it more than worth the nominal cost difference.

* Power Commander V is bike specific.
* Autotune must be used with PCV, but is NOT bike specific.
* Wide Band 2 is not bike specific, and can even be used with cars
(if used as a stand-alone unit for monitoring only).

Power Commander V Installation on the Grom

Installation of the PCV on the Grom is one of the simplest things you can do. It's literally plug and play with no wiring at all required. The folks over at Hard Racing have created a YouTube video that outlines this install, so I won't reinvent the wheel here. I will post a couple links - the first link showing the installation of the PCV on the Grom, and the second link showing the basics of using the PCV software on a Windows PC. As a bonus, the first video shows what you'll get in the box.

Keep in mind that the second part of the fist video shows information regarding installation of the less-awesome Autotune module for the PCV, NOT the Wide Band 2 module. I will provide information on the Wide Band 2 module specifically below. Skip to 5:00 in the first video to see the PCV installation.

Thanks to Hard Racing for posting these videos.

PCV Install

PCV Software

Wide Band 2 Wiring/Installation on the Grom

Before reading what I've written below in regards to the install, make sure you read through the instructions that come with the Wide Band 2 controller. The full instructions contain information regarding how to mount and angle the wideband O2 sensor that comes in the kit, and other important information for a complete install, which I will not outline below. The below information is GROM SPECIFIC, and is important to know when specifically installing the WB2 unit on a Grom, since the installation manual that comes with the WB2 is not vehicle specific, or even motorcycle specific... since the WB2 can be installed on cars as well.

If you want to take a look at the installation manual for the WB2 before you purchase one, it can be found here:

When you install a Wide Band 2 unit on the Grom in conjuction with the Power Commander V, you must make the following connections from the permanently-attached harness connected to the WB2 module:

Red wire - This needs to connect to a 12V switched source. This is a source that receives a +12V current when the bike is turned on.

Black wire - This needs to be grounded to a chassis ground / the battery ground directly.

Black/white wire - This needs to be grounded to a chassis ground / the battery ground directly. You can tie this wire and the black wire together and ground them in the same place if you'd like.

Green wire - This wire needs to be connected to the wire which would otherwise be connected to your factory O2 sensor. The easiest way to do this is to cut the wire at the factory O2 sensor about 2" from the sensor itself, and feed the wire on the harness side back up under the seat to connect it to the WB2. On the O2 sensor, you can fold the little bit of wire that's left over on to itself and tape it up to keep it clean. You can keep the factory O2 sensor installed in the bike, or replace it with a plug.

White/blue wire - The manual says that this needs to be connected to the negative side of the ignition coil. This would provide the WB2 module with an engine RPM reading. You do NOT need to connect this wire in this fashion if you are using the WB2 in conjunction with a Power Commander V. The PCV will provide this information to the WB2 via the CAN bus cable that connects the two units.

Grey wire - The manual says that this needs to be connected to the variable 0-5V lead from the throttle position sensor (TPS). This would provide the WB2 module with a throttle position reading (from 0% to 100% via a 0V to 5V range, 0V being 0% open and 5V being 100% open). You do NOT need to connect this wire in this fashion if you are using the WB2 in conjunction with a Power Commander V. The PCV will provide this information to the WB2 via the CAN bus cable that connects the two units.

The unit will come with a CAN bus cable that's used to connect the WB2 module to the PCV, along with a CAN bus termination plug. The WB2 module itself has two CAN bus ports. Make sure you don't throw away the termination plug, as it needs to be installed in the unused port of the WB2 module after you connect the WB2 to the PCV via the first CAN bus port on the WB2.

The unit will come with an O2 sensor harness, which will attach to the included wideband O2 sensor on one side, and directly to the WB2 via screw terminals on the other side. Unless you are color blind, it's nearly impossible to screw this part up. On the O2 sensor side, the plug can not be connected incorrectly, as it only fits the correct way. On the WB2 side, colors are wired "color for color" from the harness to the WB2 module.

The unit will come with a "data aquisition" harness, which has a pre-formed plug on one side and a purple, white/purple, and black bare wire group on the other side. For a WB2/PCV setup, you won't use this harness.

Per Hard Racing's experience, the following location can be used to present a clean 12V source to the WB2 during install. You can either use a dedicated mini-fuse tap to accomplish this, or you can simply strip away a small amount of insulation from the red 12V switch power lead for the WB2 and crunch it under the leg of the 10A fuse shown. Be careful not to bridge the legs of the fuse.

Several members have attempted to tap 12V switched from the license plate lead and from the tail light lead with negative results. This is not recommended.

I have posted a YouTube video showing how I ran all of this wiring on my Grom. This might be helpful to anyone performing the installation themselves:

Wideband O2 Gauge

If you opt to purchase a wideband O2 digital gauge when you purchase your WB2 module (which I highly recommend you do), the gauge will simply plug in to the harness that's attached to the WB2 module, and no other wiring will be required. The gauge itself will come with the required harness that simply plugs in on both ends (one side to the gauge and the other side to the WB2 module), so install only takes a couple of seconds. The harness that comes with the gauges from Dynojet are long enough so that you can install the gauge on the handlebars of the Grom and have enough length to run the harness back under the seat and connect directly to the WB2 without having to extend the harness. This is nice.

Custom Gauge Pod Installation

Note, however, that the gauge does not come with a mounting kit that is handlebar specific, and so you must find a third party one to install. I asked Dynojet about this, and they do not sell mount kits for handlebars. I was able to find a mount kit on Amazon that seems like it will work well. When I receive the product and get my gauge installed, I'll post an update. A link to the product is here:

[ame=] VUMAXX CD1200-52 - Universal Gauge Holder / Cup / Pod with 5 Adjustable Mounts for 2 1/16 INCH / 52MM Gauges up to 2.5 inches in Depth: Automotive[/ame]

The kit didn't really work for a handlebar mount "out of the box." It does come with a roll bar mount, which I was optimistic about using to mount it to handlebars. Unfortunately it was designed for a 1" bar, and my bars are 7/8". Even if my bars were 1" bars, the unit is supposed to be attached with hose clamps. Try as I might locally, I couldn't find any black hose clamps. Normal silver hose clamps would look like crap. I like to keep my installs clean, so didn't want to go down that road. Here you can see how the mount is supposed to fit on the bars:

After some thinking, I decided to improvise. At first I thought about making a custom bracket that I could mount to the location where my factory mirrors were (went with bar end mirrors). I thought I could go to the hardware store, find a short black bolt that would fit in the factory mirror "holes," and make a small bracket using a scrap piece of aluminum or steel to mount one of the little balls that come in the kit to, and do it that way. The more I thought about this, the more I thought that I didn't like how it would look.

A second option was to go to the bike shop and get a purpose-built handlebar mount with a ball on top. This assumed that the ball on a third party kit would be the same size ball as required for the gauge. Alas, it was Sunday, and the bike shop was closed.

I was looking at my bars, and realized that the Moose Racing bars that I bought had the same sort of steel gusset that goes across the top that most aluminum dirtbike bars have. This is typically the bar that the bar pad wraps around, and it helps strengthen the bars when you're doing typical dirtbike ****, like jumping and hooning and what not. I don't really jump the Grom, and I hate the way that the bar looks, so I removed it. I was looking at one of the two mounts that comes on the bars to support the gusset, and thought one would be perfect for mounting my gauge... I went to the hardware store and picked up a long, machined bolt that would fit, and a drill bit to drill out the center of the ball to accommodate the bolt.

Here you can see the bracket I was talking about that came on the bars, as well as both of the balls that came with the gauge mount. I ended up using the smaller of the two balls - the one without the octagonal piece on the bottom.

I carefully drilled out the ball to accommodate the size of the new bolt. If you look carefully, you'll see that the factory bracket that came on the bars is threaded on one end, so there was no need for extra bolts and washers and things. It looks super-slick once installed. The ball goes inside the bottom of the gauge so you can rotate it around the ball for a slight bit of adjustability. Unfortunately it's not a "snap fit" to get the ball inside the ball cup on the gauge cup. If you look carefully at the next pic, you'll see that the back of the ball cup slides off. It doesn't "snap" on and off either, it just sits there with friction, and you're expected to put a hose clamp around the assembly to keep it together. This works better in practice than it sounds.

The kit comes with a nice, sleek, black hose clamp that's intended for this purpose. Unfortunately it's very weak and I overtightened it and stripped it out. Not cool. I was able to replace it with a much beefier version that is much more sturdy... unfortunately it wasn't black. Fortunately (lot of fortune in this post), the kit for the gauge pod came with a black rubber boot that you're supposed to install over the hose clamp and the ball assembly to keep dirt and junk out anyway, so you can't tell that I didn't use the factory hose clamp, since the boot hides it. To keep the gauge in the pod, there's a simple set screw on the bottom.

Here's the final product. VERY sturdy and ended up looking great!


Question 1 (answered by Dynojet)

Q. Is there anything special in regards to the WB2 modules for the GROM vs any other WB2 module?

A. The WB2 modules are slightly different. First of all, if the WB2 module does not have a GREEN LED status light, the simulated narrow-band output feature does not work at all. Second, the WB2 units specifically sold to Hard Racing have had the simulated narrow-band output feature set to 0.925, which should get a Honda Grom to run at about 13.5 AFR in the closed loop range. You can change this setting on a WB2 unit in the field with our LCD-200 accessory only.

That pretty much sums it up. If anyone has any specific questions, let me know and I will update this Q&A answer section in the original post so newbies can get all of the Q&A in one place without having to scroll and read the entire post/replies.

4 Posts
Discussion Starter · #2 ·
Mods - if this should be moved to a different section, please feel free to move. I wasn't quite sure where to put it.

178 Posts
Good info, thanks

1 Posts
Nice article! I wanted to buy a auto tune first, but I need a WB2! (gauge and narrow band output)

1. The WB2 also has a analog input, can i use this as the pressure sensor for mapping?? What else can I do with it?

2. It is nice that the guys from dynojet have the narrow band output on the wide band 2 to be able to set up closed loop tuning... but this is one value for the whole closed loop range!
I'd like to be able to use the full range A/F table in the PCV and define my own A/F ratio also in closed loop area. I was thinking about just fooling the ECU by connecting a fixed voltage of 450mv to the o2 input so it won't regulate anymore and the PCV can do its thing like it also does in the WOT area. (I mean, what is the point of having a fully configurable map when you only use one column??)
Anyone tried this already? Are there other ways to prevent the closed loop to regulate (and that do not turn on the engine check light!!)?

4 Posts
Discussion Starter · #5 ·
1. I'm not sure, you'd have to ask them. The documentation is kinda thin.

2. You ARE able to adjust the close loop value (by default it's 13.5:1), but you need the LCD add-on. The Windows software only talks to the PCV, not the WB2.
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