Look at the bottom of the frame down tube, just below the drain plug and you'll see the nut/union where the rubber oil pipe leaves the bottom of the tank. You will need to remove this. First you will have to take off any bash plate you have fitted.

When you pull it out you will find the gauze strainer on the top of the union. You can give that a clean in petrol while you're at it.

With the bottom oil pipe union removed you should be able to get your stray dipstick out.

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