Fitting a foam air filter
After a lot of searching and investigation I have finally found an air filter supplier (Moto Air) that makes foam air filters to fit the Honda Transalp. The standard paper filter that the bike uses is cylindrical with a larger diameter metal plate attached at one end which serves to cover the hole in the airbox where the filter goes in and has screw holes so the plate can be screwed to the airbox thus holding the filter in place. The foam filter I have bought is simply a hollow cylindrical piece of foam, with no metal plate attached so on it's own, once it is in the airbox there is nothing holding it there and the hole in the airbox where it goes in is not covered. Now, as it happens, it fits perfectly around the original paper filter (the hole down the centre of the foam filter is exactly the same diameter as the paper filter). This would solve the problem of covering the hole in the airbox and holding the filter in place, BUT would this double layer of filtration cause performance issues? It would mean the air would first have to travel through the oiled foam filter and then through the paper filter - admittedly it would be very clean air by the time it got through, but would there be enough of it?! Anyone else come across this problem with foam filters? Or any suggestions/advice?
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