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Discussion Starter · #1 · (Edited)
Next time you're washing your bike or after a heavy rainstorm.

Remember to open up the fuel cap and check if there is any water collection in the fuel tank.

The Duke has a design flaw with regards to the fuel tank cap whereby small amount of water will leak into the fuel tank.

Even though there is a vent hose for the collected water to escape, it is too small to efficiently remove the water.

Check yours too.

Have heard that you can add denatured alcohol/methanol into the fuel tank to have the water dissolve in the alcohol which dissolves in petrol to remove the water. But perhaps those more mechanically inclined than I am can chip in and give their views.
 

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A design flaw?
I ride 2 dukes, was mine after each (longer 200+ km) ride, ride both through torrential tropical down pores (sometimes even a full day to get home) and never ever has so much as a drop of water in my tanks.
If you have taken off your tank you better check if you put it all back correctly.
The tank drain (for water during washing and or riding through the rains works a charm on my two Dukes no KTM flaws at this end.
 

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Discussion Starter · #3 ·
A design flaw?
I ride 2 dukes, was mine after each (longer 200+ km) ride, ride both through torrential tropical down pores (sometimes even a full day to get home) and never ever has so much as a drop of water in my tanks.
If you have taken off your tank you better check if you put it all back correctly.
The tank drain (for water during washing and or riding through the rains works a charm on my two Dukes no KTM flaws at this end.
It happened to mine and a few other duke gen 2 riders. It's the fuel cap that leaks water down into the tank. did not take out the cap at all since new.

Could be the vent hose that is blocked?
 

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Chuasv,

How have you determined that water entered the fuel tank?
How many other Gen-2 riders you know of claiming this 'problem'?
Is there water in your fuel tank and how did this manifest itself?


It happened to mine and a few other duke gen 2 riders. It's the fuel cap that leaks water down into the tank. did not take out the cap at all since new.

Could be the vent hose that is blocked?
 

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Discussion Starter · #5 ·
53254

This is what I'm referring to.

Met a couple of Duke gen 2 riders at a KTM meet last week and asked them if they had the same problem. Out of the 5 there, 4 experienced it.
 

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That is not water in your tank. That is water around the inlet to your fuel tank. Two vastly different things. One prevents your engine from running and causes rust on the inside of your tank, the other does not.
Hasn’t happened to my Gen2 as I do not let my bike get wet, ever. I keep my bikes clean with Plexus
 

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Indeed Chuasv,

This is the outer ring where the drain tube connects.
The water here in amounts as in your picture is absolutely normal after a wash and/or a ride in the rain.
The circular opening in your photo to the bottom right is the access to the petrol tank and is locked off from anything entering when the fuel cap is closed by a spring-assisted rubber seal.
When the fuel cap is opened you can see this and push with your finger to check the spring action.
If, for whatever reason, there is no spring resistance your fuel cap may be defective.
If the droplet of water in the 'overflow' area bothers you, you may spray this area with some silicone spray (covering the fuel entrance) for these droplets to drain off more easily however in our climate I can't see any water remaining in the overflow after a 10 - 15 minute ride in the sun.
If your concern is the drain tube might be blocked, which this tiny droplet is no indication of) you might want to blow some compressed air from the exit of the drain tube (disconnected from the charcoal canister) to see if any debris comes out at the top end (again block the fuel filler hole).
I hope this helps in setting your mind at ease that KTM pretty much knows what they are doing and such a 'flaw' would have been corrected ages ago with all the thousands of Dukes/Rc's 125, 200, 250, 390 etc. riding the planet.


View attachment 53254
This is what I'm referring to.

Met a couple of Duke gen 2 riders at a KTM meet last week and asked them if they had the same problem. Out of the 5 there, 4 experienced it.
 

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Discussion Starter · #8 ·
Right, perhaps I typed it wrongly then. hahaha.

I half suspect it could be the vent hose that is blocked. However, I checked and the vent hose goes straight to the left fairing, instead of into the charcoal canister? Or you are referring to the hole on the right side?
 
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