Dual density air filter foam

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
User avatar
monkeywithaplan
Site Supporter
Site Supporter
Posts: 236
Joined: Wed Apr 30, 2008 4:45 pm
Bike owned: NC35 and NC30
Location: Belfast. Northern Ireland
Re: Dual density air filter foam

Post by monkeywithaplan »

eltel wrote:Hi,
There's an article in MCN this week at the Q & A section regarding air filters. Basically they say the mesh is there to prevent carb back fire, Safety reasons.

Terry.
:kneel:


:lol: :lol: :lol:

:P

:scared:
Insisting on perfect safety is for people who don't have the balls to live in the real world. Mary Shafer, NASA Ames Dryden

Bikes don't leak oil, they mark their territory.
firebeast
Settled in member
Posts: 65
Joined: Sat May 03, 2008 11:40 am
Re: Dual density air filter foam

Post by firebeast »

just cut out the paper with a sharp blade and fit the foam(vut a m or 2 bigger overall so it compressess a little to keep the edges tight) with araldite or similar.did it years ago with some pipercross element.its worth doing for anyone who has a tired filter since its the last time you will need to do it.you should get a benefit provided you make sure to oil it properly as it needs the oil to trap some of the tiny particles.i tend to do it on all my bikes when it needs replacing.even my knackered old ntv work bike.
User avatar
RickOliver
Site Supporter
Site Supporter
Posts: 492
Joined: Sun May 11, 2008 8:55 am
Re: Dual density air filter foam

Post by RickOliver »

For practical reasons you need to leave the steel mesh in - the filter foam has no inherent stiffness like the pleated paper has, so if you remove the mesh it will just get sucked into the carbs...
User avatar
CMSMJ1
Moderators
Moderators
Posts: 7161
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: Dual density air filter foam

Post by CMSMJ1 »

The obvious points are often missed..


I have recently refitted my foam filter and was not impressed with the performance. It is not better than a clean paper element but it is cheaper. I also thought I was running rich with some bogging in the midrange and general poor running.

I was dismantling the bike ot steal bits for the race bike and whipped the filter off the carbs. I decided to clean the foam and found that I had the 3 sheets f HRC foam in there and also a really scabby, sticky and rotting piece of thicker foam in the middle. :whistle: Didn't recall that foam was part of my solution when I originally setup the filter..

Anyways - I binned that manky foam and went with the 3 sheets of lightly oiled HRC foam. The moto is loving it. Miles faster, revving quicker and basically a lesson in sort your filter out and make sure if you run large jets that you don't strangle the bike.
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate
moblies
Settled in member
Posts: 25
Joined: Mon Dec 08, 2008 4:18 pm
Bike owned: 93 NC30
Location: Berkshire
Re: Dual density air filter foam

Post by moblies »

Anyone know off the top of there head what size sheet I need and how many, also i have seen Dual density and single. which is best to replace the standard paper part.

cheers
Spike16
Site Supporter
Site Supporter
Posts: 1670
Joined: Tue Apr 29, 2008 8:56 pm
Bike owned: NC30 Road, SV650 Race
Location: Hampshire, Wichester
Re: Dual density air filter foam

Post by Spike16 »

iv just fitted mine and it looks good, I only got it because it ment i wont have to replace it all the time now, just clean the fact it was cheeper than an original and should perform better is a bonus
Bike_Nut
Settled in member
Posts: 180
Joined: Sun Oct 19, 2008 6:48 pm
Re: Dual density air filter foam

Post by Bike_Nut »

CMSMJ1 wrote:The moto is loving it. Miles faster, revving quicker and basically a lesson in sort your filter out and make sure if you run large jets that you don't strangle the bike.
Any hint at what jet sizes you are running? I am about to order some foam sheets and have Dyno Jets in sizes up to 130 just have taking the carbs off so want to be close with my first guess!
User avatar
CMSMJ1
Moderators
Moderators
Posts: 7161
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: Dual density air filter foam

Post by CMSMJ1 »

Bike_Nut wrote:
CMSMJ1 wrote:The moto is loving it. Miles faster, revving quicker and basically a lesson in sort your filter out and make sure if you run large jets that you don't strangle the bike.
Any hint at what jet sizes you are running? I am about to order some foam sheets and have Dyno Jets in sizes up to 130 just have taking the carbs off so want to be close with my first guess!

I am running 130s in RVF short stacked carbs and with no extra washers on an NC30 with a Yamamoto/custom twinstack system. No airbox lid, HRC tray and the rubber flap still in place on the airbox base. Hows that? :ugeek:
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

Post Reply