Air filters do we need them?

Performance wise do we need filters. Only asking because my filter element is degrading and was wondering if it really needs to be replaced. I'm in NYC and cant imagine I'll ever suck in some stones or anything but wondering if performance will be compromised in any way?

I ran a set of Amals with bellmouths instead of the filter a long time ago. Trashed the slides and bodies in one riding season. I'd imagine if you remove the filter element, you'd need to do some rejetting. But imo it's the fine dust/grit that is all around the road surface that you should worry about, replacement Carbs aren't cheap, and a filter should be a necessity.

Performance wise the 750 and early 850 filter is as good as bellmouth , it provides adequate filtering surface, this is obviously with a paper element in fair state.

Having ridden bikes without filters know from experience how fast cylinder bores and carbs slides wear without filters : dust from the road is a very good grinding paste.

NO ?



the ENGINE does .Immagine that was the carb . And it was a Granite Chip Road . In a Group of Bikes . :x
and there was 20 thou piston / bore clearance . And the rings broke up , into 16 & 20 pieces , the top ones
and half of one was not there . And only one was whole . So compression was 2/10 or 5/8 of s f a . And it
still did a 14.5 Quater . With a shot clutch . :lol:

Air Tight filter sealing on back roads is neccessary . seen all the Road Gime on Cars ? its off the road .
Then theres gravel verges on country roads , and wind, and dry days and so on . Unless you live in Antartica .
Remember the 747 that flew through a Volcano . Thats what you get in some Er ' chaps ' wake , when its
unsealed , or you live on the coast .

& in the valve guides , and oil , and bearings ,

excessive clearances can cause problems .

Aircraft and boats generally do fine w/o air filters and so should Norton aircraft and boats, duh. Ever see-feel the bug bits and grit on bare face or embedded in sliders and tank and head light, well our air flow splits around the engine to slap back together right at the carb throat - box filer area. So I say definitely run w/o filters or even half ass kn filter and let us know how long ya get away before ring wear blow by gets ya a ticket and complaints form friends and strangers here and in real world. Them kn are definitely the sexy way to ride and many may scuff at the video demo of kn's passing hand full of grit but Wes and I have repeated that experiment a number of times and now wrap UNI filter foam around ours - like baggy pants on a lovely models pelvic area. I've dusted Bon Ami through kn and Norton paper and open throats to go back to Norton paper in Norton air box.

Steve, I like your idea of a foam wrap around a K&N!

and that asks the question of why get a more "porous" K&N in the first place....

air filters aren't that much money are they to make the case of saving money buying a lifetime K&N?

Can't run air box with many the upgrade carbs installed so left with after market make do's - mostly the kn brand, and likely fine for ciean-ish city riding a long-ish time. I was harshly chided at my stupid ignorant over sight of Not Checking Ring Gaps on new engine a year ago when reporting over 0.0120's inch gaps found blowing oil and smoke out. At first I had to accept list universal assessment I was a stupid ignorant damaging level mechanic - then Wes reported same big gaps after less than two yrs with naked kn filters. Guess what that does to my opinion of list opinions of me. Wes measured gaps each time but now runs some UNI foam I gave him to cover up the cute Miki kn carb filter. I no longer capitalize wd40 either after finding its most famous features, rust protection or lube function - as just more false advertising wishful thinking.

http://www.google.com/#sclient=psy-ab&q ... 67&bih=373

speirmoor said:

Performance wise do we need filters. Only asking because my filter element is degrading and was wondering if it really needs to be replaced. I'm in NYC and cant imagine I'll ever suck in some stones or anything but wondering if performance will be compromised in any way?

Click to expand...

YES, you need an air filter. Even in the sterility of NYC, fine particulate is blowing around everywhere. The only exempt vehicles are watercraft and snowmobiles.

JRD said:

dust from the road is a very good grinding paste.

Click to expand...

When you are on secondary roads with gravel on the shoulders, driving behind any Tractor-trailer at good clip. Watch how much dust and grime gets picked up from the shock wave of air being moved out of the (Its) way. This turbulent air causes lots of debris directly behind to cause you the grief.
I have never had a problem with a stock commando filter 72-74 vintages. Some folks just do not know how to remove and reinstall them. Which leads to other solutions (K&N) or velocity stacks without filters, which leads to... other problems.
Cheers,
Thomas
CNN

Good points. Its hard to imagine that dust can do so much damage but I believe all of you and have ordered a replacement filter element. My wife said that study of mummies teeth in Egypt revealed how much sand there was in the bread they consumed. Makes me think about my air filers importance more now.