Topic: Home made Air Filter?

[campbmic]

Well I'm rebuilding a 75 CB550 and I can't get a stock airbox until Tuesday. I just finished rebuilding my carbs and want to see if they work. I was wondering if anyone has ever used pantyhose or pieces of cloth or anything as a filter. I was thinking cutting out a small piece of cloth and ziptie it over the carb intake. Has anyone done or heard of anything like this? If so what should I use to get the same amount of air restriction as an airbox?

Also, I just basically took my carbs apart, tipped them, then put them all back together. Im sure some things will be out of whack that I need to tune. What signs should I look for to tell me that my carbs are tuned funky? Anyone know of a good general guide for carb tuning for new people?

Thanks!

[blindguy76550]

i have use a pantie hose before on a four cylinder car, i have heard it helps to keep out moisture and dirt. i had no problems and ran it like that for a couple of months. so i wouldnt think it would hurt anything on a bike, but dont hold me liable for any misshapps.

[rustrocket92]

Filters are over rated! I have a car with over 300,000 miles on it and the only filter it has is a chunk of stainless mess. No paper or cloth element what so ever and it is still tickin. So if you are just going to fire it up to make sure they don't leak I would say LET ER RIP!

[the technological J]

i think u could possibly start and run ur bike with out a air filter but that back pressure is  important for proper tuning.... but make sure ur carb  air fuel screws are tuned to stock speck and ive heard of ways to "bench" sync carbs but i dunno cause i have a manometer... but might be worth a search

[754]

If other dont wear out their motors in a few years with open carbs, I doubt you will harm yours in 3 days...

[Gordon]

Don't bother trying to fine-tune your carbs for optimum running without a regular filter in place if you plan on putting one in later on.   

[mgbgt89]

I knew a kid in highschool that was putting an intake on his brand new diesel dodge ram. He had to go to the parts store for a cone filter and put a sock over the intake tube. Went down the road, spooled the turbo and sucked the sock right in. I think it was like a 4500 dollar repair at the dealer to replace the turbo.

You shouldn't have a problem with that, unless you've got a turbo.

[fmctm1sw]

I would have never thought of using a panty hose...  I bought a CB 500 filter off eBay and hope to alter it for use on a 350F.

[markjenn]

Despite the whacko "I put a half-million miles on my turbo Yugo doing the Baja without a filter" testimonials, filtering is absolutely important to a long and healthy engine life, even for a engine that doesn't see many unpaved roads.  Having said this, it's a long-term thing and unless you're working in a dirt-floor garage, there's no reason you can't fire it up without filters until you get your intake system sorted.

Do the panty-hose trick if it makes you feel better, but I doubt it's worth the trouble.  You're relying on the fact your running with little/no filtration will be brief, not that you've found a substitute for a proper filter.

As others have said though, I wouldn't do a whole lot of fine tuning with your temporary setup.  Certainly you can correct major issues, but I'd postpone things like jetting until later.

- Mark

[CBJoe]

Also, I just basically took my carbs apart, tipped them, then put them all back together. Im sure some things will be out of whack that I need to tune. What signs should I look for to tell me that my carbs are tuned funky? Anyone know of a good general guide for carb tuning for new people?

Thanks!

Did your carbs have a problem prior to removing them? 

Did you follow your manual's rebuild procedure for the carbs?  Or did you really just disassemble and reassemble?  Cleaning the jets and passageways are a must unless you want to repeat the removing and cleaning cycle over and over.  Do it once and do it right.
There are TONS of posts here about rebuilding and tweaking carbs.  Plenty to search and read. 

As others have said, running without final air filter configuration is OK if you just want to see if the bike will run.  You wont, however, be able to check/tune the bike without the final filter configuration.

Cheers, Joe

[Beans]

Ran no filter for 2 months. u should be ok to make sure it works and doesn't leak.

[BobbyR]

I had a air filter like that on my old Ducati, something more like a mesh. Years later when I went to tear down the motor, the cylinder walls looked like someone went at it with a rat tail file.

[fmctm1sw]

I had a air filter like that on my old Ducati, something more like a mesh. Years later when I went to tear down the motor, the cylinder walls looked like someone went at it with a rat tail file.

I had a guy that builds (auto) racing engines hone my bores for a 350F.  I took my pistons to him and he said "see those tiny scratches on the top sides of your pistons?  That's from not running an air filter."  But agreed, leaving them off to sort out immediate issues shouldn't cause destruction.  That is, of course, if you don't suck panty hose into your engine...   

[BobbyR]

Not to say that Pantyhose does have a place:

[rustrocket92]

I am not saying filtering is not required but I can tell you from my expierence that it shouldn't hurt to start the motor with out the filters. I would not try to tune it as other have said. I am just saying that if you are mid build and your filters haven't come in yet go ahead and fire it up. Its not going to hurt unless you live in the Mojave and there is a sand storm brewing.

[w1sa]

I am not saying filtering is not required but I can tell you from my expierence that it shouldn't hurt to start the motor with out the filters. I would not try to tune it as other have said. I am just saying that if you are mid build and your filters haven't come in yet go ahead and fire it up. Its not going to hurt unless you live in the Mojave and there is a sand storm brewing.

I agree.
That being said, I've seen holes in stretched pantyhose big enough to let, ummh, (golf) balls through.......

[Queeg]

I knew a kid in highschool that was putting an intake on his brand new diesel dodge ram. He had to go to the parts store for a cone filter and put a sock over the intake tube. Went down the road, spooled the turbo and sucked the sock right in. I think it was like a 4500 dollar repair at the dealer to replace the turbo.

You shouldn't have a problem with that, unless you've got a turbo.

wow i just got a chuckle, then a full on roflccoptor. man i bet he wouldn't do that again.....

  now on the right subject. just to do a test fire like a few others said it will be fine. for tuning you need something to make a vacuum in the throat of the carb  to draw the fuel from the bowl, to tune properly and run under load you'll need something there.

 just don't put a sock in front of your hx-35 please.