TOPIC:

I am still of the firm opinion along with many others, that the standard / stock Z/KZ1300 Air Filter Element has a very restricting effect on the overall running of our bikes, resulting in a Rich burn / mixture.
The single inlet spout to the airbox behind the RH side cover is also very small for the amount of "suck" the 3 large carbs demand.

I have ran 1300's in the past without the filter element inside the air box and it does definitely "breath" easier and feels smoother, but its obviously not a good idea to do this for long and risk dirt and other stuff getting through to the carbs and engine. Many owners run the bike without the top air box tool tray fitted to increase air flow too.

The other "mod" many years ago was to drill a series of 13mm holes in the air box unit around the air filter element, to increase the overall air flow in, but again not something I really want to do and spoil the air box.

I dont want to fit POD type filters as I want to retain the standard look and air box of the bike, and have found the K&N reuseable filters dont really make things any better either.

So................my question is, has anyone experimented with this and came up with a filter or system which will fit INSIDE the standard air box to increase air flow whilst retaining the standard look !
Something on the lines of a sponge or foam element inside, which increases air flow but also keeps the dirt at bay ?

With all due respect..................I can ask for opinions all day long on this topic and formulate many myself, but what I am looking for is someone who has actually done this rather than what they "think" it may do, which will not help at all ?

Experiences appreciated as ever.............

Pete F
UK.

Hello mate, I did remove the upper airbox on mine & then re secured the standard shape K&N element in the original place with the plate above the filter housing (I think that plate is a plastic tool tray on the carb models) & studding going into the original threaded holes that hold the upper airbox on. So essentially the whole of the filter is open at the rear. I did it to gain some extra room as I needed to move the charging regulator to between the filter & battery when I was customising my bike. Bike seems to run OK

Don't want to debate the pros or cons of the stock air filter/air box but will comment on: "a very restricting effect on the overall running of our bikes, resulting in a Rich burn / mixture."
The "Enrichment System" causes the spark-plugs to soot and give the impression that the carbs are rich. I removed the 3 Enrichment piston/diaphragms earlier this year and reduced this issue and got 5 MPG more. I've had another 1300 in the shop with lots of carb related issues. Of the many things I had to do I removed the enrichers on this one, as well. The owner just called and stated that on the ride home it ran as smooth as a babies bottom with NO issues !
My point is: If the concern about running rich ( or appearing to) is what's driving the exploration for an alternative air filter system, then try this easy modification first.

Hi Scotch,

Thanks for your reply and I will soon be removing and completely stripping my carbs for a winter full re-furb and carrying out your Choke Air Mod which I am looking forward to doing. You did also mention with that mod you had removed the 3 x enricher circuit diaphrams and sealed the small covers with a gasket. I intend to do this too as you have suggested.
Maybe I will leave the original filter system until I try the carbs on the bike after the mod and see how it goes.

The main reason for asking the Air Filter Question was that the bike does run better and smoother without the standard filter element in the airbox, but hopefully your mod will sort it anyway.

Pete F
UK

I'm interested in hearing about your Enrichment Mod. I've done two now. A third conversion with no issues with the exhaust making noises and cleaner spark-plugs would further confirm. Easy to reassemble if this isn't the case.