Product Description
warning-sign-small.png The first generation standalone ECU has been superseded by the new 2015 standalone ECU / Datalogger for narrow band and wideband O2 sensor.
All new Yuminashi Ultimate 164cc kits shipped after March 24 2015 include the new 2015 standalone ECU with Datalogger!...
● Click here to download the MSX 164 Ultimate Owners Manual.
● Click here to download the user guide for the new 2015 Standalone ECU / Datalogger
● Please open this PDF file and use it as a guide to gain both, maximum performance and maximum protection against engine knock (very important).
● With its proven powerfull and reliable 160cc kit as its predecessor the all-new 164cc Ultimate kit is with the 1mm larger piston even a greater value for money kit where the Yuminashi R&D is not only introducing a slightly larger piston, but also a lighter piston with a molybdenum coating on the skirt to have less friction.
With the Ultimate 164 kit you will have just like its predecessor a kit with improved performance/reliability without any risk of damaging the stock crankshaft or big end bearings and where you have the choice to select between a 12,000RPM limited Racing mode or a 10,500RPM limited Touring map which is really pleasant and perfect for touring with a lot more power compared to stock with still a surprising fuel economy. (A graph is attached to the pictures to see the dyno differences between stock and other big bore kits...)
Changing the map/mode is very easy. Once you have your stock ECU unit removed and our new stand alone ECU unit installed, you can select the Racing mode with installing the jumper that comes with the kit. With the jumper removed you go in to the touring mode where the RPM's will be cut at 10,500RPM's and this will allow you to make a very safe top speed of 130Km/h or 80,78Mph with no risk at all on engine damage.
In the Racing mode you can drive as extreme as you want with a very safe state of mind because the Yuminashi R&D have covered this as well with programming the ignition timing and fuel injection amount in the standalone ECU based on the engines temperature.
If your engine temperature runs really high and your engine needs a break, then the ECU is programmed in such a way to give your engine a break with reducing the pre-ignition and adjusting the fuel injection amount to keep you away from piston and serious engine damage.
With all of this we can state very easy that the Yuminashi Ultimate 164 kit is the safest kit for MSX/GROM125 on the market concerning durability and reliability where all parts where blue printed in combination with the stock throttle body and air filter.
(If you use the stock air filter you need to remove the restriction inside the stock air filter like you can see on this video from Motorcycle Projects on YouTube).
Your top speed in the Touring mode (RPM limited mode) will be 130Km/h (80mph), top speed in the non limited RPM mode will depend on the weather/road conditions and your personal body weight/hight.
The 10-holes MSX/GROM big bore injector that comes with the kit guarantee a short and powerfull injection and you don't need to install a larger throttle body or EFI controller to control the air fuel ratio because the standalone is programable (need to order the optional USB Programmer Cable)...
Set comes complete with the SX290 8.2 high lift camshaft, and also with the special high lift valves to make a higher lift as stock possible.
The reinforced clutch springs that comes with the kit make sure that you don't miss one single RPM.
The piston from this 164cc Touring Kit is plug and play to be installed with the stock 125cc head.
This piston rings are produced on strict Japanes standards and since March 2015 are all rings treated with a hard chromium plating layer (Cr).
To read all details/information about the piston rings you can click on this link.
The new 2015 Yuminashi Stand-alone ECU / Datalogger is the new generation of programable ECU units for Honda MSX125/GROM125 and is replacing the formal, first generation of Yuminashi stand-alone ECU units.
With the new generation we have build the programmable ECU based on your needs to make it as easy as possible to tune your PGM-FI engine and included both, a narrow band and a wide-band AFR meter in the package to make accurate datalogging possible.
Like this you can see exactly next to each value in the map how much the AFR ratio is from this particular spot in the map and like this it becomes really easy to know if you have to increase or decrease the percentage from that particular value in the map to get your optimal AFR target.
You can use the AFR values which you can see in one of the pictures as a guide to get your optimal AFR targets for the Honda MSX125/GROM125.
We strongly would like to suggest to use the wide-band feature from the new ECU with buying a BOSCH 4.6 or 4.9 wide-band O2 sensor and a bung to be welded on the exhaust where you simply can connect the white wire from the BOSCH O2 sensor to the green wire from your new Yuminashi stand-alone ECU / datalogger, and where you connect the red wire from your BOSCH O2 sensor then to the 12V current after the contact switch, and the black wire from the BOSCH O2 sensor to the ground from your battery or frame.
The next thing you need to do then is to select the wide band sensor option in your software and you're good to go...
You need to order the optional USB Programmer Cable if you don't have one yet (the one from the formal stand-alone ECU generation can still be used), because you will need this cable to make the ECU work based on your local enviroment conditions!
If you haven't a USB Programmer Cable yet, then please don't think that you won't need it, you can order it over here...
* Click on the CD's below to start downloading the software for the stand alone PGMA-FI ECU-DATALOGGER correcting program: