Everything I Know About Snatchy Throttle and TPS Settings
What is snatchy throttle?
Everyone has a different experience. Some don't even notice it. My definition is a sudden engine deceleration when the throttle is turned off followed by a sudden acceleration when it is turned back on. Most noticeable when slowing down for corners and accelerating out of them. However lightly you twist the throttle grip, you cannot overcome this sudden switching off and switching on again. This causes the transmission to "snatch" and the bike to become jerky.
The reason this occurs is that on deceleration, the ECU switches off the fuel 100%. It does this for emission control reasons. Then however slowly you twist back on, it comes on again 100% with a bang. There are no subtle, incremental transitions. It's just on or off.
If you are used to a bike that doesn't do this, it can ruin your whole experience. You can with some acclimatization, adjust your riding style, to somewhat compensate but it's always there, however good you are with the throttle.
This problem, was most prevalent on the earlier 2015-2017 models, when some owners complained that the bike was "un-rideable". The later 2018-2019 models (I own a 2019) did not suffer perhaps as much but it was still annoyingly there.
Why Does it Happen?
This on off problem is caused by the ECU detecting a 0% throttle position and cutting the fuel 100%. It's called the Deceleration Fuel Cut Off. It's like hitting the kill switch. It just kills the motor and feels like you have put the brakes on. The reverse happens when you twist the throttle back on, it feels like you've switched the engine back on and released the brakes. There are some other factors involved, like it does not kill off the fuel if you are under 2,500 rpm (at least on the 2019 model it doesn't) or you are riding above 7,000 rpm or you don't close the throttle 100% or you get back on the throttle in 1.5 seconds after you have turned it off.
These symptoms are exacerbated as soon as you start modifying the air intake and exhaust systems. These bikes are lean running from the factory and when you add freer flowing air filters and exhaust systems, you make them even leaner. This creates more snatch and very poor performance and smooth running at lower throttle openings (where we spend 90% of our time) is totally compromised.
What has been tried to cure this?
In the early years, there was a lot of time spent trying to adjust the TPS to reduce the snatch, as it was found by getting it to a certain setting, the snatch would be eliminated.
There were varying degrees of success with different voltages and settings used for this adjustment. The TPS adjustment set from the factory seemed random, as some reported it to be correct (at the right voltage - whatever that was meant to be) and others reported it to be off. Earlier models could be adjusted using the -COO method and the later year models could only be adjusted using a breakout cable and measuring the voltage. Then some complained that once the TPS was adjusted, it sometimes become impossible to switch Traction Control settings once you were on the move or even at all.
It was never going to be a total fix. Adjusting the TPS (to whatever setting worked) was only a way of trying to fool the ECU into thinking the throttle had not been shut 100% and therefore it would not activate the deceleration fuel cut off. This was a hack rather than a fix and setting the TPS was so sensitive that only some people managed to get it to work inside the parameter that it didn't stop the Traction Control from working correctly. (The Traction Control settings can only be changed when throttle is 100% off. So if you have changed the TPS and you are tricking the ECU into thinking the throttle is never closed 100% when the engine is running, you will never be able to change the Traction Control settings). But some people did get it to work, as the deceleration fuel cut off had effectively been eliminated.
Another problem that was reported with this hack, was that fuel consumption went up. Well it would do. You are telling the ECU that the throttle is open when it isn't, on top of which, the fueling map is shifted sideways, so that more fuel is being added across the range at all throttle positions (which might also be the reason some people said that by adjusting the TPS you would also get smoother running of the whole engine. You would do, as this lean running engine loves a bit more fuel).
Other things you could do that would help were to get a throttle tamer (not necessary on later models as they came with the bike), take slack out of the throttle cables, adjust your riding style or learn to live with it.
Suzuki even replaced the ECU for some complaining owners on earlier models but it didn't help (they never addressed the deceleration fuel cut off issue, they only adjusted some of the fueling maps), the snatchiness was still there.
Some of the ECU flashing guys caught onto the problem and offered ECU flashes as the cure. Some with new dyno produced fuel mapping and others with just a mail in ECU flash. But it was never openly discussed as to what the flash was actually changing or if the deceleration fuel cut off was turned off. Was it adjusting the fuel maps or some of the settings? The results were mixed. A lot of them got great results and their customers were very pleased, especially if the dyno chart showed more HP and torque.
For some, changing the fuel mapping with a Power Commander piggy back system would also help. Usually this was because extra fuel was added across the lean areas, especially at lower throttle openings (from 5% to 25%) and again, this would mask the deceleration fuel cutoff problem.
Others tried the Booster plug system, which basically adds fuel all round and again reduces some of the problems with the lean condition.
But, unless the ECU was modified with the removal of the deceleration fuel cut off, the snatchy problem was still lurking however much it was being masked. It may have felt somewhat better riding the bike but it was always going to be there.
Everyone has a different experience. Some don't even notice it. My definition is a sudden engine deceleration when the throttle is turned off followed by a sudden acceleration when it is turned back on. Most noticeable when slowing down for corners and accelerating out of them. However lightly you twist the throttle grip, you cannot overcome this sudden switching off and switching on again. This causes the transmission to "snatch" and the bike to become jerky.
The reason this occurs is that on deceleration, the ECU switches off the fuel 100%. It does this for emission control reasons. Then however slowly you twist back on, it comes on again 100% with a bang. There are no subtle, incremental transitions. It's just on or off.
If you are used to a bike that doesn't do this, it can ruin your whole experience. You can with some acclimatization, adjust your riding style, to somewhat compensate but it's always there, however good you are with the throttle.
This problem, was most prevalent on the earlier 2015-2017 models, when some owners complained that the bike was "un-rideable". The later 2018-2019 models (I own a 2019) did not suffer perhaps as much but it was still annoyingly there.
Why Does it Happen?
This on off problem is caused by the ECU detecting a 0% throttle position and cutting the fuel 100%. It's called the Deceleration Fuel Cut Off. It's like hitting the kill switch. It just kills the motor and feels like you have put the brakes on. The reverse happens when you twist the throttle back on, it feels like you've switched the engine back on and released the brakes. There are some other factors involved, like it does not kill off the fuel if you are under 2,500 rpm (at least on the 2019 model it doesn't) or you are riding above 7,000 rpm or you don't close the throttle 100% or you get back on the throttle in 1.5 seconds after you have turned it off.
These symptoms are exacerbated as soon as you start modifying the air intake and exhaust systems. These bikes are lean running from the factory and when you add freer flowing air filters and exhaust systems, you make them even leaner. This creates more snatch and very poor performance and smooth running at lower throttle openings (where we spend 90% of our time) is totally compromised.
What has been tried to cure this?
In the early years, there was a lot of time spent trying to adjust the TPS to reduce the snatch, as it was found by getting it to a certain setting, the snatch would be eliminated.
There were varying degrees of success with different voltages and settings used for this adjustment. The TPS adjustment set from the factory seemed random, as some reported it to be correct (at the right voltage - whatever that was meant to be) and others reported it to be off. Earlier models could be adjusted using the -COO method and the later year models could only be adjusted using a breakout cable and measuring the voltage. Then some complained that once the TPS was adjusted, it sometimes become impossible to switch Traction Control settings once you were on the move or even at all.
It was never going to be a total fix. Adjusting the TPS (to whatever setting worked) was only a way of trying to fool the ECU into thinking the throttle had not been shut 100% and therefore it would not activate the deceleration fuel cut off. This was a hack rather than a fix and setting the TPS was so sensitive that only some people managed to get it to work inside the parameter that it didn't stop the Traction Control from working correctly. (The Traction Control settings can only be changed when throttle is 100% off. So if you have changed the TPS and you are tricking the ECU into thinking the throttle is never closed 100% when the engine is running, you will never be able to change the Traction Control settings). But some people did get it to work, as the deceleration fuel cut off had effectively been eliminated.
Another problem that was reported with this hack, was that fuel consumption went up. Well it would do. You are telling the ECU that the throttle is open when it isn't, on top of which, the fueling map is shifted sideways, so that more fuel is being added across the range at all throttle positions (which might also be the reason some people said that by adjusting the TPS you would also get smoother running of the whole engine. You would do, as this lean running engine loves a bit more fuel).
Other things you could do that would help were to get a throttle tamer (not necessary on later models as they came with the bike), take slack out of the throttle cables, adjust your riding style or learn to live with it.
Suzuki even replaced the ECU for some complaining owners on earlier models but it didn't help (they never addressed the deceleration fuel cut off issue, they only adjusted some of the fueling maps), the snatchiness was still there.
Some of the ECU flashing guys caught onto the problem and offered ECU flashes as the cure. Some with new dyno produced fuel mapping and others with just a mail in ECU flash. But it was never openly discussed as to what the flash was actually changing or if the deceleration fuel cut off was turned off. Was it adjusting the fuel maps or some of the settings? The results were mixed. A lot of them got great results and their customers were very pleased, especially if the dyno chart showed more HP and torque.
For some, changing the fuel mapping with a Power Commander piggy back system would also help. Usually this was because extra fuel was added across the lean areas, especially at lower throttle openings (from 5% to 25%) and again, this would mask the deceleration fuel cutoff problem.
Others tried the Booster plug system, which basically adds fuel all round and again reduces some of the problems with the lean condition.
But, unless the ECU was modified with the removal of the deceleration fuel cut off, the snatchy problem was still lurking however much it was being masked. It may have felt somewhat better riding the bike but it was always going to be there.
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