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Mapping the GSXS1000GT

This is quite a different beast to the 2019 GSXS1000F I previously mapped. The biggest difference being the Fly-by-Wire throttle system, that allows 3 different settings on how the throttle plates open in relation to the amount of throttle applied at the twist grip. On this new model, they have completely eliminated the snatchy throttle that so plagued the earlier 2016-2021 bikes. This is primarily due to the new throttle system, which allows for far greater control over the on-off-on fuelling of the bike. The other differences in the ECU maps that I have noticed so far include: 1. There are no secondary throttle plates on this model 2. The O2 sensor can now be disabled in the ECU. Previously you could only disable the F1 light that was produced if the O2 sensor was removed. So now you can disable the O2 sensor (and it's associated fuel mapping) without actually taking it off or unlugging it. 3. Turning off the Deceleration Fuel Cut now has a dramatic effect in reducing engine brak

More Snatchy Throttle Stuff and a Cure

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Here is a link to the GSXS Thread about Snatchy Throttle and my response and cure: https://www.gsxs1000.org/threads/snatchy-throttle-issue-fixed.42028/page-12#post-398682 There is some confusion here. There are 2 issues being discussed. One is the snatchy throttle and the other is surging and poor fueling at low throttle opening. They are 2 different things which require 2 different fixes. There is also some confusion over the generic term "flashing". When you flash an ECU there are about 50 options you can play with. These include changing the fuel mapping, switching off various functions, changing idle rpm, changing the fan temp switch and so on. When you get your ECU flashed, it is essential to know what to ask for or at least know what the shop is going to change. Using the Woolich Racing Tuning software, the most effective option, to improve the bike, (we are not talking about more HP) is to disable the Deceleration Fuel Cut. This completely eliminates the on off s

Snatchy Throttle - Technical Explanation

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Here is the snatchy throttle (don't get confused with other issues like surging at cruise, dips in the power band and so on): With a stock GSXS (certainly on my 2019 F model) I have mapped what happens to the fueling on my dyno. Up to 2,500 rpm, if you shut the throttle there is no fuel cut off when the throttle is closed. After 2,500 rpm and up to about 7,000 rpm, once you close the throttle (completely 100% closed), the ECU software will activate a 100% fuel cut off AFTER 1.5 seconds. If you get back on the throttle before the 1.5 seconds, then there is no snatch (snatch is caused by fuel coming back in with a bang - like you turned the ignition back on). If you missed the 1.5 second time slot, you cannot avoid the snatch. HOWEVER, if you allow the bike to coast back down to 2,500, the fuel will start again EVEN at 100% closed throttle. Thus avoiding the snatch. Above 7,000, if you close the throttle 100%, there will still be fuel flowing, but if you allow the rpm to d

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 a