[kirkn]

OK, Bill, question-time again.

My (mom's) CB200 needs air filters, and I've read your description of how you did it, but I must be dense, here, I'm not "seeing" it...

If I burn that pleated paper and glue out, what keeps the rubber intake boot from melting, too?

Then, if you lay in a custom-cut bit of Uni foam from a sheet, where do you attach it? To the tiny little lip on that outer metal cover? With some glue? That lip is only ~ 1/8" wide. Did that work? Or, did you just cut a small bit of foam to cover up the opening where the rubber tube attaches?

Thanks,

Kirk

 

[tbpmusic]

You just take the rubber part off, Kirk.
It comes off pretty easily, just glued in sort of - reinstalls with a bit of silicon.

Be sure to burn it outside, unless you get off on epoxy fumes.........
If it gets really hot, the metal framework might get a little loose , it's just soldered together.
Once again, silicon comes to the rescue and holds it together.
Cut your foam slightly oversize, and push it down into the accordian pleats on the metal part. A dab of silicon works here too.

You'll see once it's burned off, it will be obvious - there's a metal screen insode that wraps all the way around - that keeps your foam from getting sucked in to the motor.

 

[jayel]

just glued in sort of - reinstalls with a bit of silicon.

Once again, silicon comes to the rescue and holds it together.

A dab of silicon works here too.

http://www.shop3m.com/60455029946.html? ... p-Adhesive

 

[kirkn]

Will do! Thanks for the tips.

I saw that the rubber tube just looked like it'd come right off, but wasn't sure I wanted to take the 'step of no return' And I didn't realize there was any framework inside.

Thanks, that's how I'll do it.

And thanks for the 3M tip, Jayel. I have that very stuff onhand from a previous project.

 

[kirkn]

Worked like a champ! Thanks for the tips. Picked up the sheet of Uni-Foam at my local cycle parts shop for ~$10. Got enough left over to make the foam replacement element for my Hodaka restoration project.

 

[tbpmusic]

There ya' go, buddy - glad to have helped....

Now don't forget to oil them up good - not enough oil, and it will run real lean.

 

[kirkn]

Y'know, I wondered about that...

On the one hand, every foam element air filter I've ever used needed to be oiled, including dirt bikes both 2- and 4-stroke, and every lawnmower, too.

And yet, every paper element filter, including the original one, and all automotive ones, do not get oiled.

I was wondering if this bike would run lean if I didn't oil it, or would it run rich if I DID oil it, since it was originally a non-oiled paper element. And the bike is showing signs of running rich anyway, although I think that's just float level...

Haven't done anything yet. I just haven't gotten to it.

Hmmm....

 

[tbpmusic]

Yeah, you need to oil them.
From the experience of my own CB200 I can say that merely going to the foam filters will lean things out - you'll be moving a lot more air.

 

[musicmark]

I wanted to add my endorsement to this technique, as I used it myself recently. My bike is a 1971 CB175K5; the filter was very similar to the one in the photos but not exactly the same.

As far as I could tell, the ONLY thing holding mine together was epoxy; no signs of solder. The more I burnt it, the easier things became. Epoxy which had been charred black all the way through could be easily chipped and scraped off the metal, whereas epoxy that still had any yellow color to it did NOT want to let go.

So my advice would be to get it burning good, and let it go until it burns itself out. Don't expect the metal pieces to hold together once you're done; if your filter is like mine, they'll fall apart once you burn the epoxy. Then you'll be able to give all the parts a good cleaning.

I reassembled the parts with RTV adhesive I had lying around. Considered JB Weld or other epoxy, but a bead of silicone gave me a strong enough bond, and will be easier to deal with if I ever want to take it completely apart again.

Another note: This was my first experience with oiling a foam filter. I apparently got about the right amount in one filter. The other one, though, dripped out all over the floor after a few days. I recommend propping them up on some newspaper, in the same orientation they'll be on the bike, and watching a couple days for drips. Unless you're sure you know exactly what "saturate with oil, then squeeze out excess" means.

 

[CB200]

My 200's filters are not yet to the replace point but I did worry about this one. Has anyone tried methylene chloride paint and epxoy stripper inplace of fire? Also what about cannabalizing a paper filter, trim the hight and with and repack. The 3M glue looks like OEM.


Each time I go to customise a part I get a second part, the best of the two I save for show only. One day I may be too old to ride, but not show.

 

[tbpmusic]

My 200's filters are not yet to the replace point but I did worry about this one. Has anyone tried methylene chloride paint and epxoy stripper inplace of fire? Also what about cannabalizing a paper filter, trim the hight and with and repack. The 3M glue looks like OEM.


Each time I go to customise a part I get a second part, the best of the two I save for show only. One day I may be too old to ride, but not show.

I simply don't like to mess with methylene chloride, as it's really bad stuff - I've already fought off cancer once, would like to avoid a repeat.......
For that reason, I prefer to just burn 'em.......outside, well away from anyone - but whatever works for you.

I've heard anecdotal reports of guys doing that with paper filters (your cannibalizing comment), sounds acceptable to me.

 

[jayel]

Also what about cannabalizing a paper filter, trim the hight and with and repack. The 3M glue looks like OEM.quote]
I bought paper a lawn mower filter wider than needed so I could cut off the edges to the width I needed for my cb350 and cb450 filters counted he number of pleats needed and put them back together looks stock and works great, DO NOT oil or get paper filters wet it seals the pores (swells the fibers) in the paper and chokes off the air flow, oiling a foam filter the oil clings to the foam strands which won't swell but traps the dirt

 

[CB200]

Thanks guys--and I got the methchloride on my skin in the past and tryed to wash it off--the water on top of the stuff sent the vapor into my skin- burned me- so it's wipe off then wash--that bad a carcinogen?

 

[deathhare]

What did the OP do to increase fueling to match the added air flow?

 

[SkyeMaloney]

Thread resurrection! I just wanted to thank the OP for taking pics of the process!!!

 

[CBok]

Hello guys,
Im planning on doing this with my cb 200 air box, a few questions:
1. You guys used the fine type of filter foam right? Would there be any advantage to using a layer of fine and a layer of coarse foam?
2. How much foam do I want to use?
3. What did you use to get the old filter burning? Gas?

Thanks much

 

[Patriot66]

Hello guys,
Im planning on doing this with my cb 200 air box, a few questions:
1. You guys used the fine type of filter foam right? Would there be any advantage to using a layer of fine and a layer of coarse foam?
2. How much foam do I want to use?
3. What did you use to get the old filter burning?

Thanks much[/QUOTE

Literally did mine yesterday, remove the carburettor hose/ ram pipe, I cut out the old element as best as I could with knife and then pulled out with grips. I then used a hot air gun which was hot enough to burn off the paper/glass element and leave the epoxy virtually intact, followed by a quick dust down and a coat of primer to tidy up.
I used a single layer of Ramair (UK brand) dual layer filter foam which only cost £5gbp for a 300mm x 200mm sheet, I then sealed all around the foam and the replaced carb ram pipe with an automotive grade RTV silicone. Re oiling, I contacted Ramair and they said that it wasn't necessary to oil their element so I'll just up jet as a dry element is more consistent than an oiled one for jetting IMO.

Just ridden the bike now, definitely needs up jetting but not much - I have a local dyna centre so I'm just going to pay £60 to get it right.

 

[warhead_71]

Just refurbished my 76 CB200T air filters. Pulled the rubber snorkels out, then set it on fire to burn out the paper and epoxy. Had to burn it extra-crispy to get all of the epoxy off. Cleaned up the metal with a brass wire wheel. Chopped up a $10 donor filter from Autozone and glued it back together with Gorilla Glue. I also included the outer wire mesh to protect it from vermin. Turned out great and the bike is breathing easier. In all I spent about 3 hours on the project... not too shabby.

 

[bilbikek411]

Nice work

 

[LBH2243]

I really like the way you did that warhead. Looks nice with the wire mesh and added protection from little guests. Ill have to do this soon on my CB175K6 as the filters are toast. She runs crazy rich now...