Cheap 'Pod' filters - why you shouldn't - Public service posting

The problem with keeping your K&N's on for that length of time is they progressively get plugged up. I wash my UNI's on a regular basis. You'd be surprised by the amount of crap you get out of them after only a month.
If you want your jetting spot on and to stay that way, IMO a washable filter is the way to go...
 
Walms said:
The problem with keeping your K&N's on for that length of time is they progressively get plugged up. I wash my UNI's on a regular basis. You'd be surprised by the amount of crap you get out of them after only a month.
If you want your jetting spot on and to stay that way, IMO a washable filter is the way to go...

K&N's are washable as well and with the metal mesh, don't fall apart after a lot of washings, they work best with a little dirt, but not too much. I have had one in my nissan for 7 years, washed it 2 times. Had one in a civic that went 12 years and washed 4 times at 60K mile intervals 100K KMs. I have yet to get either for a bike but the CX I am working on now will get either Uni's or K&N depending on the budget, almost bought the cheapo's but with the info here, I am going to one of the 2 name brands. My GL is destined for an OEM K&N Replacement this spring.
 
K&N's filter better as they get 'plugged up' (it's in their advertising)
I clean mine whenever I swap bikes ;D
 
crazypj said:
K&N's filter better as they get 'plugged up' (it's in their advertising)

Similar to spray painting a pair of glasses black and calling them efficient sunglasses... :)
I believe this thread got started because of poor flowing air filters... Just sayin. ;)
 
Not poor flow filters, bad design closing off various ports
K&N still flow more air than stock filters, even when you can't see the wire mesh because of dirt build up.
You know when they are restricting flow as they change shape (and are then scrap)
Cheap pods will distort because of flow restriction even when they are new
 
Ok, we will have to agree to disagree... ;)
My first post on this thread, I mentioned the requirement to jet up when I made the move from K&N's to UNI's... This is proof enough that the UNI's flow better.
The only negative I've ever heard about UNI's is they look like crap but I can live with that if I get better performance.

I should mention that it is also a known issue with piston port 2 strokes that there is a relationship between the flat back side of the K&N style filters causing tuning difficulties because of the reversion wave bouncing of that plate... This is why allot of triple guys have made the move to a K&N replacement filter for the air box or the UNI's.
This isn't to say they don't work at all, just that it adds another variable to tuning issues.
 
I also have rather a lot of experience with piston port two stroke's (and reed valve Yamaha's plus disc valve Suzuki's)
I've always found Uni's to be slightly more restrictive than K&N, if you had to jet up it's probably due to flow reversion with K&N, as you said, fuel mix bounces off 'back wall' of filter
I wouldn't use anything but Uni on RD350/400 (air cooled)
the extra length makes a major difference
Britain had (and still has) less restrictions on two strokes so they were available for a lot longer than in the USA
 
A couple posts up you claimed to swap filters with bikes, now you're telling me that UNI's are more restrictive than K&N's... ::)
BTW, Both my triple and your RD's have reed valves so there is no reversion wave. ;) The need to jet up is because there is less restriction, just like I need to jet up again to run open carbs.
 
That's not strictly accurate. I know we think that reeds close off and that there can be no reversion wave, but there is. It's just a heck of a lot smaller than PP 2 smokes. :)
 
Walms said:
A couple posts up you claimed to swap filters with bikes, now you're telling me that UNI's are more restrictive than K&N's... ::)
BTW, Both my triple and your RD's have reed valves so there is no reversion wave. ;) The need to jet up is because there is less restriction, just like I need to jet up again to run open carbs.

Nope, I CLEAN filters and swap them onto new bike
Unless someone specifically want's modified bike I put it back to stock (stock bikes tend to be worth more to the majority of people)
Size for size, Uni's ARE more restrictive, the ones I use are roughly double the length of K&N
Not my RD's, never had one but worked on hundreds
What triple do you have with a reed set up?
I don't remember it on any of the Suzuki's or Kawasaki's
 
My bike has John Aylor's reeds...
True Teaser, they don't hold water but unlike a piston port, I need to oil the UNI's or they stay dry. ;)
 
http://home.roadrunner.com/~jbplock/ISO5011/SPICER.htm
I posted this once before, can't remember where though.
It isn't motorcycle filters but does show filtering capabilities
 
Maybe I should jury rig this unit I have with a hair dryer and do the test myself... ;)
I'll check with my buddy's to see if they have a K&N to borrow.
To be fair, my prejudice goes back to before I had reeds. I've never tried K&N's on this motor.

7D7FCFEA-EF37-4F89-886A-DC64C773322D-214-0000000FC90EBA77.jpg
 
Damn, haven't seen one of those flow meters since the early 70's 8)
I you checked the ISO 5011 test, you'll see K&N are only good for keeping out boulders and small children ;D
 
This isn't where I bought mine but this is the unit... I got it after I put the bike up for the winter so looking forward to testing it out in the spring for syncing the carbs. It is supposed to be more user friendly than the Uni-syn as it doesn't kill the flow.

http://www.alamomotorsports.com/weber/synchronizers.html
 
They work better than normal vac gauges on two-stroke motors, we used them on T500 race bike and stuff without airbox
 
I have read and read and possibly reread threads on pod filters, uni and k&n`s in my search for the answer to ditching the oem airbox or not. What I am getting is pods on an 81 honda cb400t is gonna make it gasp for air like a fat kid after gym class. Will K&N`s or Uni`s give a better result or am I opening up a jetting nightmare?
 
If you change anything in the intake tract that changes flow, you are going to need to re-jet. It's not that pods create a moving target but you will need to understand what the motor needs and what to change to correct it.
 
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