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I recently bought a KTM Adventure 390. When I start the bike in neutral and then shift to first gear, the bike moves(jerks) forward a little, even though the clutch lever is still pulled all the way. Is this normal?

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  • Define "moves forward"... jerks a little forward as the inertia of the gears is absorbed? Or takes off down the road under full power?
    – Solar Mike
    Nov 7, 2021 at 12:02
  • Thanks for pointing it out. I have edited the question.
    – positron
    Nov 7, 2021 at 13:07
  • Welcome to Motor Vehicle Maintenance & Repair! Nov 7, 2021 at 14:20
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    I'll only comment because I think jwh20's answer is probably correct- but I've noticed similar behavior on my dirtbikes when the clutch cables aren't adjusted correctly and the clutch isn't being fully engaged on a pull. Though if that's the case, you'll notice a consistent pull/roll forward and not just a small pull forward.
    – rob
    Nov 8, 2021 at 15:32

3 Answers 3

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This is common among all motorcycles that have a "wet" clutch system. What that means is that the clutch is surrounded by fluid, usually engine oil. Even though you have the clutch pulled in which disconnects the clutch plates, there is still oil surrounding both the input and the output parts of the clutch. So there is some rotation from the engine being transferred to the input shaft of the transmission gears and this causes the "jump" you experience when you go from N to 1st. The technical term for this effect is called "viscous coupling".

Motorcycles that have a "dry" clutch such as some Ducati models, don't do this as there is just air which doesn't transfer enough rotational force to create the same effect.

Bottom line is that this is entirely normal and it's not a problem that needs to be corrected.

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This could also be due to a loose clutch cable. On some motorcycles, there is also an adjuster found where the cable connects to the clutch and you might need to tighten the cable there. This shouldn't impact the clutch lever too much.

https://www.ktmduke390forum.com/threads/adjusting-clutch-bite-point.23770/

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before you start it you can "break the clutch loose" by kicking the bike over with the clutch pulled in. when she kicks free- you're set to go

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    Welcome to Motor Vehicle Maintenance & Repair! I'm not sure how this answers the question from the OP? If you would, ensure you've read how to write good answers from the Help Center, as it will tell you what we're looking for as far as answers go. Feb 15 at 23:49

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