The actual filter element space in the filter housing measures 16cm wide x 28.5cm long. Bit of an ebay fail that one.
​​​​​​Good idea to physically check the fitted filter size so you order the right one.

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Just bought and fitted another new air filter of the correct size. But the airbox is distorted with heat and age. The sides are well bowed inwards. It's the same cheap nasty plastic they used on older motorcycle rear mudguards.
I'll be keeping my eye out for a new airbox at the right price.
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