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Looks like a generic "piggyback" device and there's no reason it cannot do just what the labeling indicates. With light mods, like intake/exhaust, this ought to give more than enough adjustment range. That said, the further you deviate from stock, the more variables...and that's where life can become complicated.

The OEM will start with a base fuel map table, having hundreds of cell values that correspond to manifold absolute pressure (MAP a.k.a. vacuum) & rpm, with a throttle position sensor (TPS) enrichment table overlaid. Lastly, O2 trim allows the system to make on-the-fly AF adjustments and the ECU to "learn"; that only applies to the closed-loop portion of system operation. With a narrow-band O2 sensor, speed-density systems usually go into open-loop mode beyond ~50% of peak engine output. There's no "learning" function in open-loop mode, the base map values had better be right or you'll have a sub-optimal result.

Big increases in displacement, rpm and hp can be expected to greatly change airflow curves from anything the OEM could have expected when creating the stock maps. Thus, it's likely that doubling hp and increasing rpm 3K over stock will introduce fueling requirements beyond what the stock maps and a 3-band TPS-based module can cover properly. Issues could be anything from "hiccups" in throttle response to huge increases in fuel consumption, to fatal lean conditions.

Just like college "isn't the 13th grade", EFI setup & tuning is not carburetion taken one step further...it's another, highly-technical, world.
 

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Just wait for a dynojet PC unit.

Nothing yet, short of the yoshimura exhaust, screams "Gotta have it." So far it all looks like a bunch of hokey parts looking for homes.
 

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I called Bazaaz last night and they said they had been talking with Yoshimura to develop some kind of EFI tuner for the Grom. He said to ask again on Monday to find out if anything had come of it.

I also recently purchased a used EFI throttle body from a CBR 125. I'm going to see if I can adapt it to fit on the MSX.. The plan is to put my light bore injector in it and see if the TPS and IAC will either be plug and play or at least the MSXs mount onto the CBR throttle body. I may have to fabricate some adaptors on my lathe or milling machine, but it would be interesting to see if it will work. I believe the CBR 125 throttle body is 30mm. If it doesn't work, oh well I'm only out $40, but if it does it might be a nice option for saving some money and offering more airflow. I'm optomistic because the 31mm throttle body that Roman fit to his MSX was clearly rigged to fit onto the head.

In the meantime it would be very helpful if anyone has a power commander III, V or a EJK box on their CBR 125 and also a Grom and verify that the 33 pin ECU is the same as on the GROM.
 
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