lawdog
Well-known member
So I wanted to provide some basic helpful information to those that are tuning their bikes. There seems to be a rash of “help me with my ECM” threads on here lately. This is more or less a quick summary and some information that I hope will help keep you from frying your ECM. (and along the way being able to explain your problems better so we can understand and help)
For starters read up on the tuning guide on ECMSPY’s website. It’s a great wealth of information to help you understand what your bike is doing.
To simplify you have an ECM (Electronic Control Module), the physical box so to speak, that is the “brains” of the bike. It receives data from the various sensors, interprets the data, then determines how much fuel, timing, etc to give the motor.
Inside the ECM is the EEPROM (Electrically Erasable Programmable Read-Only Memory). You could think of this as the software of the ECM. It is labeled BUEYD, BUEZD, BUE1D, etc. You (or the computer software you use) makes edits to the EEPROM to make changes to the bike.
Couple important points here.
1. Do not try to burn an entirely different EEPROM to your ECM. EEPROM’s are different sizes, with different configurations, and can easily brick it. On the same note don’t also switch ECMs unless it has been programmed to the bike (such as another stock one of the same EEPROM) or an EBR.
2. Always make a copy of your stock EEPROM and save it in multiple locations. This is your go to backup if you screw up you can fall back on. Also useful for tracking changes.
3. Be surgical when you make changes to your EEPROM. Know what changes you are making, why you are making them, and what you want to happen. If you start just making a whole bunch of changes at once and the bike doesn’t run right can you go back step by step to figure out where you went astray?
4. Know what maps (fuel and timing) you are changing. For example, if you richen up the map across the board, the bike is still going to want to lean out the closed loop region to maintain stoich. So then you are going to end up with a bad global correction and a bad running bike. Remember to keep the closed loop region at 14.7 afr and look at the big picture when making changes.
5. Just changing your map to match a race ECM may not always work. I always recommend taking the time to tune or pay someone to do it. Every bike is different and we are all in different locations with regard to atmosphere conditions. Generic maps don't always get satisfactory results. Sometimes spot on. Other times fail.
6. Don’t forget to check sensors, wiring, plugs, fuel, etc when tuning. An errant sensor, rubbing wire, bad gas, fouled plugs, etc can drive you crazy chasing problems.
7. Worst case scenario if you completely screw up, then load your stock EEPROM back. If you are still up the creek then take the bike to the dealer and ask them to flash it to the most current revision. You will either be back to stock on the bike or have a bricked ECM that needs replaced.
I hope this helps provide a basic foundation. Tuning these bikes really opens them up and makes them scream. But you have to do it right or otherwise you are in for a frustrating time. Happy tuning!
Brett
For starters read up on the tuning guide on ECMSPY’s website. It’s a great wealth of information to help you understand what your bike is doing.
To simplify you have an ECM (Electronic Control Module), the physical box so to speak, that is the “brains” of the bike. It receives data from the various sensors, interprets the data, then determines how much fuel, timing, etc to give the motor.
Inside the ECM is the EEPROM (Electrically Erasable Programmable Read-Only Memory). You could think of this as the software of the ECM. It is labeled BUEYD, BUEZD, BUE1D, etc. You (or the computer software you use) makes edits to the EEPROM to make changes to the bike.
Couple important points here.
1. Do not try to burn an entirely different EEPROM to your ECM. EEPROM’s are different sizes, with different configurations, and can easily brick it. On the same note don’t also switch ECMs unless it has been programmed to the bike (such as another stock one of the same EEPROM) or an EBR.
2. Always make a copy of your stock EEPROM and save it in multiple locations. This is your go to backup if you screw up you can fall back on. Also useful for tracking changes.
3. Be surgical when you make changes to your EEPROM. Know what changes you are making, why you are making them, and what you want to happen. If you start just making a whole bunch of changes at once and the bike doesn’t run right can you go back step by step to figure out where you went astray?
4. Know what maps (fuel and timing) you are changing. For example, if you richen up the map across the board, the bike is still going to want to lean out the closed loop region to maintain stoich. So then you are going to end up with a bad global correction and a bad running bike. Remember to keep the closed loop region at 14.7 afr and look at the big picture when making changes.
5. Just changing your map to match a race ECM may not always work. I always recommend taking the time to tune or pay someone to do it. Every bike is different and we are all in different locations with regard to atmosphere conditions. Generic maps don't always get satisfactory results. Sometimes spot on. Other times fail.
6. Don’t forget to check sensors, wiring, plugs, fuel, etc when tuning. An errant sensor, rubbing wire, bad gas, fouled plugs, etc can drive you crazy chasing problems.
7. Worst case scenario if you completely screw up, then load your stock EEPROM back. If you are still up the creek then take the bike to the dealer and ask them to flash it to the most current revision. You will either be back to stock on the bike or have a bricked ECM that needs replaced.
I hope this helps provide a basic foundation. Tuning these bikes really opens them up and makes them scream. But you have to do it right or otherwise you are in for a frustrating time. Happy tuning!
Brett
