air filter help

[Carlriddle]

Trying to come with air filter for zx600.  Probably need clamp on style straight to the 4 carbs.  Any suggestions.

[Enemy]

I know K&N's website is a big help for all sorts of dimension combinations. I would use it then cross it over to a UNI. Are you looking to stay with one filter per carb? I do believe K&N also offers single filter dual boot, but it has been a while since I've seen those although.. Definitely put an outerwear on them though..just my .02

[405dentech]

If you switch to a UNI filter you cannot run an outer wear. They use a different oil than a K&N. if you use an outerwear on a UNI it will soak up the oil and won't let the motor breath.

[Enemy]

If you switch to a UNI filter you cannot run an outer wear. They use a different oil than a K&N. if you use an outerwear on a UNI it will soak up the oil and won't let the motor breath.

YES..sorry, implied the outerwears towards the K&N.. thanks for pointing that out.

[Admin]

I believe with a uni you can get the same foam as a prefilter to wrap the base filter...

[405dentech]

[405dentech]

Wait a minute. I just re-read your post and it made since this time. I have been drinking!!!

[Carlriddle]

Bought the set 0f 4 K & N's at Auto Zone, cheaper than online price??  Gonna get some outties next.  Have run K & N on my 2-stroke quad for 10 years.  Been happy with it. 

Gotta fire this thing back up.  Getting close!!

[405dentech]

I K&n filters on everything because they make more power and you never have to replace them. Good luck with getting yours running. Mine is still a little ways away. Can't wait tho the anticipation is killing me!!! 

[artie on edge]

Air filters are another "black art", I guess it depends upon what your are doing with your machine, mine is purely a competition use and that requires slightly differing air filter set up to a recreational machine.

Its al about air velocity, the manufacturer of your engine had an airbox set up in a specific way. To get the very best out of it you need to do something a little similar.

In my case that mean bell mouths (trumpets) on the carb inlets encased in an aluminium air box with at least 50mm of clearance at the front of the trumpet. The air box can then have any filter you like.

The issue is air has "fluid like" tendencies and mass, it doesnt like to change direction once its moving and it doesnt like getting moving if its stationary. Therefore a smooth approach to the carb or throttle bodies is required (the trumpet) and no sharp radiuses immediately before the trumpet (hence the 50mm min clearance at the front of the trumpet).

For rec use, plant the filters immediately in fron tof the carbs or throttle bodies and adjust your fuel to suit, for racing use (using all available ponies), you need to do a little more work..... aint it fun??

[Enemy]

Air filters are another "black art", I guess it depends upon what your are doing with your machine, mine is purely a competition use and that requires slightly differing air filter set up to a recreational machine.

Its al about air velocity, the manufacturer of your engine had an airbox set up in a specific way. To get the very best out of it you need to do something a little similar.

In my case that mean bell mouths (trumpets) on the carb inlets encased in an aluminium air box with at least 50mm of clearance at the front of the trumpet. The air box can then have any filter you like.

The issue is air has "fluid like" tendencies and mass, it doesnt like to change direction once its moving and it doesnt like getting moving if its stationary. Therefore a smooth approach to the carb or throttle bodies is required (the trumpet) and no sharp radiuses immediately before the trumpet (hence the 50mm min clearance at the front of the trumpet).

For rec use, plant the filters immediately in fron tof the carbs or throttle bodies and adjust your fuel to suit, for racing use (using all available ponies), you need to do a little more work..... aint it fun??

Lots of fun! and very good info!

[plkracer]

Another name for them are velocity stacks.

[Admin]

actually, a good taper bore on the carb as well improves air flow, and adding velocity stacks will even make better improvements...

[fabr]

[artie on edge]

I like your stuff Mast, and IMO you are correct, I think my point tho was the manucafturer spends lots of time and money on designing an airbox system for a reason and we ignore this and when we remove it and whack a set of filters immediatley on the face of the inlet tract of the throttle body or carb.

Suddenly we need to remap ro rejet, all this is rarely ot the benefit of the engines power output.

All my engines (car or bike) have used an "airbox" system with the basic parameters as mentioned before and these effects are "feelable" thru the seat of the pants as opposed to having the filters right on the face of the Tb/carb.
 

The little car in the avatar pic has a 1.2 litre engine and has been radared  in a straight line at 185kms per hour (115mph) on a rough dirt track. Now thats getting everything a little engine has to give.

I think I mentioned somewhere that it would spin to 10k but was useable to just over 8k... and thats where the poor thing had to live with very little torque on hand...