Arctra
Husqvarna
AA Class
Hello guru's
Recently I took the leap into the magic world of fuel injected dirt bikes with my 2010 Husqvarna TE450 that uses the MIKUNI D42 EFI throttlebody. I guess I was somewhat naive about the benefits of EFI over traditional carbs, thinking that out of the box it would perform perfectly without the need for carb mods to prevent bogging and get throttle response bang-on. After just 2 rides I can see there is still a place for tuning though. So I have done some reading, but thought a single "beginners" thread might be useful. So any help/advice/opinions would be welcome.
From what I have read, there seem to be basic de-restricting mods (similar to carb bikes) that help recover performance lost to emissions limiting devices. In the case of Husky I think they are called Power-up mods and involve removing the oxygen sensor from the exhaust (and adding a jumper to close the circuit), removing the throttle stop from the throttlebody, and replacing the air filter cage so the bike can suck in more air. All of that had already been done to my bike when I got it, as well as the addition of a map switch button that lets me choose between dry and wet maps. What isn't clear to me is whether this is an ignition map, EFI map, or both - anyone have any idea?
After the de-restricting mods is where I get lost though. From what I can make out there are 2 main options:
1) Re-program the stock ECU (assumin bikes have Engine Control Units like cars)
2) Add a "piggy back" system such as the Dynojet Power Commander V (and its optional Autotune module - more on this later). These systems intercept input and output signals to/from the ECU to trick the bike into performing better. Similar to the ECU it can be reprogrammed.
Within the 2 main options mentioned there seems to be further options
1) Re-program the stock ECU
i) Load generic maps - Using the manufacturers ECU software (I think Husky uses iBeat, but there seem to be 3rd party apps as well) simply reflash the ECU with other peoples custom maps. I know this is/was common in car tuning, and can give very good results for vry little effort. Because every bike is different though, it will never get all the performance potential of the engine as it is a compromise.
ii) Customise map - I believe this normally involves running the bike on a dyno with specialist equipment to take air/fuel exhaust measurements, power output, etc. I presume it uses the manufacturers ECU software to make adjustments to the stock map. Presumably there is also more complex software that tuners have access to for modeling the maps and writing custom flash files?
2) "Piggy-back" systems (specifically the Power Commander V)
i) Re-program map - There seem to generic maps for the PCV as well as options to adjust various "blocks" using the software supplied with the unit.
ii) Autotune - Works with the PCV and a wideband oxygen sensor to adjust the fuel mapping while riding. Seems to be something of a realtime dyno.
iii) Custom map - Once again, involves using a dyno to customise the map on the PCV. The main advantage of the PCV over re-programming the stock ECU is that to get the bike back to stock all you have to do is unplug the system. Also you can use the same unit on multiple bikes (as long as you reflash it for each bike)
So, have I got things about right? Any corrections, additions, or anything?
The main problem I have is that when you snap the throttle the bike doesn't react instantly like on a well tuned carb bike. But given that issue I suspect the engine has more to give, which is why I'm investigating the options. The 450 has enough power, but if I can get it delivering the power more predictably and when I would like it, that would be great.
Recently I took the leap into the magic world of fuel injected dirt bikes with my 2010 Husqvarna TE450 that uses the MIKUNI D42 EFI throttlebody. I guess I was somewhat naive about the benefits of EFI over traditional carbs, thinking that out of the box it would perform perfectly without the need for carb mods to prevent bogging and get throttle response bang-on. After just 2 rides I can see there is still a place for tuning though. So I have done some reading, but thought a single "beginners" thread might be useful. So any help/advice/opinions would be welcome.
From what I have read, there seem to be basic de-restricting mods (similar to carb bikes) that help recover performance lost to emissions limiting devices. In the case of Husky I think they are called Power-up mods and involve removing the oxygen sensor from the exhaust (and adding a jumper to close the circuit), removing the throttle stop from the throttlebody, and replacing the air filter cage so the bike can suck in more air. All of that had already been done to my bike when I got it, as well as the addition of a map switch button that lets me choose between dry and wet maps. What isn't clear to me is whether this is an ignition map, EFI map, or both - anyone have any idea?
After the de-restricting mods is where I get lost though. From what I can make out there are 2 main options:
1) Re-program the stock ECU (assumin bikes have Engine Control Units like cars)
2) Add a "piggy back" system such as the Dynojet Power Commander V (and its optional Autotune module - more on this later). These systems intercept input and output signals to/from the ECU to trick the bike into performing better. Similar to the ECU it can be reprogrammed.
Within the 2 main options mentioned there seems to be further options
1) Re-program the stock ECU
i) Load generic maps - Using the manufacturers ECU software (I think Husky uses iBeat, but there seem to be 3rd party apps as well) simply reflash the ECU with other peoples custom maps. I know this is/was common in car tuning, and can give very good results for vry little effort. Because every bike is different though, it will never get all the performance potential of the engine as it is a compromise.
ii) Customise map - I believe this normally involves running the bike on a dyno with specialist equipment to take air/fuel exhaust measurements, power output, etc. I presume it uses the manufacturers ECU software to make adjustments to the stock map. Presumably there is also more complex software that tuners have access to for modeling the maps and writing custom flash files?
2) "Piggy-back" systems (specifically the Power Commander V)
i) Re-program map - There seem to generic maps for the PCV as well as options to adjust various "blocks" using the software supplied with the unit.
ii) Autotune - Works with the PCV and a wideband oxygen sensor to adjust the fuel mapping while riding. Seems to be something of a realtime dyno.
iii) Custom map - Once again, involves using a dyno to customise the map on the PCV. The main advantage of the PCV over re-programming the stock ECU is that to get the bike back to stock all you have to do is unplug the system. Also you can use the same unit on multiple bikes (as long as you reflash it for each bike)
So, have I got things about right? Any corrections, additions, or anything?
The main problem I have is that when you snap the throttle the bike doesn't react instantly like on a well tuned carb bike. But given that issue I suspect the engine has more to give, which is why I'm investigating the options. The 450 has enough power, but if I can get it delivering the power more predictably and when I would like it, that would be great.