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Discussion Starter · #1 ·
just purchased my ktm 790 and its my first time with a quick shifter. was wondering why it gives a little hiccup when I shift up from 1st to 2nd and how can I fix that?
 

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I used to be a distributor for HM Quickshifter and wanted to help some lurkers understand a QS a little better. The way a quickshifter works is that it senses the pressure on the shift lever and increases/decreases (based on shifting down/up, respectively) the fuel going to the motor. The electronics have a set time for the blip, typically 30-150 milliseconds, during which you are manually transitioning to the next gear.

To add to the correct replies above,about it being because you're slipping from 1st > N > 2nd, it's also that fractional extra time to move into 2nd gear that's adding to the size of the hiccup. You can test that by shifting into 2nd, normally, as you have been, and then trying it under harder acceleration and then trying it with more pressure on the shifter. You'll see that it's noticeably smoother when you add more acceleration into the mix or when you actuate the lever into the next gear faster.

As good as the electronics package on the Duke is, I'm surprised they don't offer adjustments for kill-times. On my race bike I have added 20ms to the upshift to 2nd and downshift to 1st

Some after market options for reference... Comparison Guide | HM Quickshifter It's very impressive that it offers downshifting, which is why I'm surprised there isn't an adjustment option via the dash.
 

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Discussion Starter · #6 ·
I used to be a distributor for HM Quickshifter and wanted to help some lurkers understand a QS a little better. The way a quickshifter works is that it senses the pressure on the shift lever and increases/decreases (based on shifting down/up, respectively) the fuel going to the motor. The electronics have a set time for the blip, typically 30-150 milliseconds, during which you are manually transitioning to the next gear.

To add to the correct replies above,about it being because you're slipping from 1st > N > 2nd, it's also that fractional extra time to move into 2nd gear that's adding to the size of the hiccup. You can test that by shifting into 2nd, normally, as you have been, and then trying it under harder acceleration and then trying it with more pressure on the shifter. You'll see that it's noticeably smoother when you add more acceleration into the mix or when you actuate the lever into the next gear faster.

As good as the electronics package on the Duke is, I'm surprised they don't offer adjustments for kill-times. On my race bike I have added 20ms to the upshift to 2nd and downshift to 1st

Some after market options for reference... Comparison Guide | HM Quickshifter It's very impressive that it offers downshifting, which is why I'm surprised there isn't an adjustment option via the dash.
That makes a lot of sense. I guess I just forgot to think of it that way. The hiccup is just the skipping of the "neutral" gear from 1st to second. I have notice shifting quicker and less harshly tends to make a smoother transition. Thanks for the info!
 

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Also, if you want to feel the quickshifter in action, you could cruise down an empty road at ~30mph in 3rd and put VERY light pressure on the shifter, as if you were getting ready to upshift to 4th. Slowly apply more and more pressure and, at a certain point, you'll reach the activation pressure of the quickshifter. If you do it without enough pressure to change gears you'll feel the systems "blip". It's a gentle hiccup. If you went into gear, congratulations, you pre-loaded your shifter. On bikes without a quickshifter, that's how you shift without the clutch, the only difference is that you do a quick blip of the throttle to smoothly transition into the gear instead of the QS doing it for you!

Super simple concept but very awesome results!
 
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