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I've had them on my 73 cb350 since I have had it last year and I think they are due for a cleaning. Anyone else use these airfilters? I never re-jetted my carbs with them. Did anyone here feel the need to do so? I'm going to wash the socks with Dawn dish soap but I'm not sure what to oil them with. What do you folks use?
 

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Honestly I won't use them as they have no flame-arresting properties, and based on where they sit on the bike I prefer to not roast my nuts in the event that a carb backfire set the fuel in them on fire.
 

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Honestly I won't use them as they have no flame-arresting properties, and based on where they sit on the bike I prefer to not roast my nuts in the event that a carb backfire set the fuel in them on fire.
and a paper element does?
 

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I have a set and used foam element sticky for ATVs. I thought that my 350 hesitated a bit at about 45 mph at times. I bought a couple of 75 jets for this reason but have not installed them or put the bike on the road yet this season. I plan on using the filters on the current bike I am building too. $14 for the foam filter material will cover two bikes.
 

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I was just looking for info of the same thing, I just put got rid of my original paper filters and airbox yesterday and swapped in for the UNI foam filters. I did notice the OE airbox covers won't fit back on with the supplied spacers kit though. I've ridden about 50 miles on them with no re-jetting, but it's definitely getting more air and running a bit lean. I pulled the plugs and they are a little white, and it hesitates a bit under heavy throttle in higher RPM range. I was just going to tune the air/fuel mix before tearing into the carbs....but still trying to figure it out.
 

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Discussion Starter #8
I was just looking for info of the same thing, I just put got rid of my original paper filters and airbox yesterday and swapped in for the UNI foam filters. I did notice the OE airbox covers won't fit back on with the supplied spacers kit though. I've ridden about 50 miles on them with no re-jetting, but it's definitely getting more air and running a bit lean. I pulled the plugs and they are a little white, and it hesitates a bit under heavy throttle in higher RPM range. I was just going to tune the air/fuel mix before tearing into the carbs....but still trying to figure it out.
Yeah my plugs were running a little lean as well. I just bought the uni cleaning kit posted above. Waiting on them to totally dry before I oil them. Maybe having a properly oiled filter will help with the slight lean mixture.
 

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and a paper element does?
Paper elements have a metal screen flame arrester on the inside of the element, so Yes, paper elements have a flame arrester.

I have used the Uni filters, and a good flame backfire could ignite them.

I did not rejet, but when I returned to the stock air filter, the bike ran better. I weny online and found a complete air box and filtrers of good quality. Bike starts quick, runs well with the stock air box. Better than foam filters, better than those little emgo pod filters.

If you really examine the stock system, the two filters are interconnected and the carburetors feed from both. Thge two filters have a lot more surface area thgen the individual filter elements of the pod/sock type and provide a larger still pool of air to draw from, resulting in better carburation and thorough filtering.

To improve even slightly on it, you would neeed to engineer a complete system. There is no bolt on/screw on system that is better than stock.

The Pods decrease performance and are strictly for looks, not smooth running.

I am talking about a stock intake system. If you are changing everything, then all bets are off. Most aftermarket bolt on attempts I've seen are not really improvements at all....They lose something, smooth idle, easy drivability......Even proven race improvements don't take to driving in traffic well.....
 

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I just picked up a set of these uni filters for my 450 k3 and them seem just a bit too big for my carbs and when I tighten them they seem to want to slide off easy. also the right carb seems rather close to battery tray for filter to go on straight. and suggestions??
 

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I should clarify, I use the uni foam material in place of the paper pleats on the stock metal.
 

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I should clarify, I use the uni foam material in place of the paper pleats on the stock metal.
That is what I do/did.

 

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I used Unifoam on stock frames. I just got my bike going and haven't worked out all the bugs yet so probably shouldn't comment on the filters. I should add that I over-oiled mine and, because the foam is siliconed to the frame, I cannot rinse and wring out - I can only soak in gas. Lesson to learned...don't over oil - Franz recommended 1 tspn of oil.

unifoam filters.JPG
 

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Did any one use the actual uni foam filters? They have very small pod filters I am looking at. The main thing I am trying to do is avoid re jetting as I am not to savvy on it and get real filters on my bike.

I might add I have a cl350
 

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SL175's appear to have used a UNI-FOAM type filter on their stock filter cages right off of the showroom floor.
 

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The problem with pods and socks is that they do not have the proper stack length into the carb. Instead of laminar flow, the entrance air is turbulent, which creates pressure pockets that vary, and poor air flow through the carburetor.

I have a K&N filter on my NH740. It replaces the stock filter so I get the advantage of better air flow, while retaining the the proper stack dimensions and a plenum for the carbs.

When it is time for a new filter on my CB360, I will replace the stock paper element with a UNI foam element, retaining the stock configuration for the rest of it.

Most people are not really concerned about performance or easy starting and running as they are for looks. Pods look nice, short, neat, but they detract fromo performance (performance not being top speed and such, but driveability and easy starting and good throttle response).

Pods never improve on performance, the small ones actually have far less surface area and ability to flow proper CFM than stock.

Like painting a cow pie, it does look shiny, but it is still what it is.
 

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The problem with pods and socks is that they do not have the proper stack length into the carb. Instead of laminar flow, the entrance air is turbulent, which creates pressure pockets that vary, and poor air flow through the carburetor.

I have a K&N filter on my NH740. It replaces the stock filter so I get the advantage of better air flow, while retaining the the proper stack dimensions and a plenum for the carbs.

When it is time for a new filter on my CB360, I will replace the stock paper element with a UNI foam element, retaining the stock configuration for the rest of it.

Most people are not really concerned about performance or easy starting and running as they are for looks. Pods look nice, short, neat, but they detract fromo performance (performance not being top speed and such, but driveability and easy starting and good throttle response).

Pods never improve on performance, the small ones actually have far less surface area and ability to flow proper CFM than stock.

Like painting a cow pie, it does look shiny, but it is still what it is.
I agree with the statement about intake length and pods, but I think it's a huge leap to state that they never improve performance. I have large pods with long intakes on my bike, paired to long exhausts, jetting and shimming. The bike starts easily, idles smoothly and performs quite well. I don't have a dyno to back it up, but I would bet it pulls harder than a stock setup throughout the RPM range.

photo3.JPG
 

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You definitely addressed the intake stack length with them. But keep in mind,, you have a separate filter for each cylinder. On stock, BOTH air filters are connected by the balancing tube. The filtering area is double the size of one stock filter. So you may actually have a little less filtering area with our setup....But it still is the right way to go with this. You are using large pods....The problem is with the small cone pods, which have a very small surface area, and generally do not filter well as the pores are larger to help reduce the pressure drop that small size causes. Plus the direct mount pods often block the carb ports, as stated earlier.
 
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