Just wondering what people are using for filtering bike carbs. There are a few options out there, socks, cones, boxes, sponges etc. So post up your pictures with a detailed description of what you've used please

yours looks at home just with trumpets mate

Check my latest post in the faq dude!

Yeah but currently they are not fixed down with anything. And I need some sort of filtering. Don't want crap getting in.

originally i ran a dome pipercross across all 4 which worked great but looked abit big and dopey, then i changed my carbs and it wouldnt fit so currently ime running some £20 single ebay jobbies and they look really good and do the job :)

will try and find pics of both for you

edit: found them

Edited 13 January, 201214 yr by dubownerbilco

Your best option is a properly calculated airbox.

Wish i had no servo

Max, I know. It's going to be a compromise between form and function, and I think form will win!

Craig, do this filters cover the whole trumpet. Also, how are your trumpets held in? The tops of the jets are exposed on my trumpet side of my carbs. Are these ok to cover up?

Copied from my post on the FAQ....

And yes this is dubownerbilcos old filter. I did it this was as I wanted all the air tubes to be filtered too, and ultimately I wanted something that was gonna last and keep the slides clean. I hope this gives you some ideas.

I decided quite early on that I wanted to use a proper filter, not socks, so the brass tubes could flow ok. So bought one of these from dubownerbilco as he no longer needed it. link

As the back face of the carbs wasn't flat, I had to make some spacers. Heres the carbs, note the step on the left.

I bought some nylon from eBay and after getting crafty with a dremel, and a drill, I made these, not pretty but functional.

Heres how, using the bike airbox as a template

And some neoprene rubber to make it air tight.

ready for air filter now!

Baseplate made out of 3mm alu for a few quid from eBay.

Made

Now for building it together.

Edited 13 January, 201214 yr by runforrestrun

I read that forrest, thanks. What are those brass gasket type things?

Craig, how are you filtering your breather tubes with just the cones?

I read that forrest, thanks. What are those brass gasket type things?

Craig, how are you filtering your breather tubes with just the cones?

well ime just so lucky that the carbs ime using at the moment have a large round tube slightly sticking out the back of each carb and everything is contained inside so i can just clamp the filters around that without any problems, basically looks as though they were made for single filters!

Edited 13 January, 201214 yr by dubownerbilco

I read that forrest, thanks. What are those brass gasket type things?

Craig, how are you filtering your breather tubes with just the cones?

They are basically one piece washer things for the four bolts. They came with the carbs and sit in the airbox. The tabs should be bent down to stop the bolts loosening and going into the intake but no chnace with my set up as the bolts are a lot longer than the original bike ones.

I ran 4x cone filters, they were okay just eBay specials so SHOCKING quality, you'll also need ones that go over the trumpets AND brass air jets.

Apparently they can cause issues with setup, but I balanced mine with the filters on and all cylinders seemed to run equal.

It was only about 3 weeks before they'd started coming apart so I bought an airbox.

Tbh an aluminium airbox that encloses all 4 with a single filter and a DECENT cold air feed of your best bet. The heat soak at the back of my engine back sucks, I need a bonnet scoop or something!

So I fitted an airbox, this ones the 70mm deep option, I wanted the biggest I could squeeze in.

Only issue is that due to brake servo and length of inlet manifold I had to offset it, which really pissed me off.

My carbs had little stubs on them which held the trumpets in and had a flange you could use for mounting filters...like runforestrun made.

So these 4 plates (4x screws in each)

Also have a flange on them, can see here...

Hope this helps.

Btw, this is why I avoided foam filters...

That's inside my airbox opposite the trumpets, so that's where fuel has sprayed etc

Ah cool. I didn't have those stacks so I made my own. Of course I can see how the tubes would be filtered now too. Me likey.

Why are your carbs spattering fuel the wrong way?

Can you send us a link to where you got your airbox from? Would be quite easy to mod that for a cold air feed I reckon.

Edited 15 January, 201214 yr by runforrestrun

Its barely anything, thats just after like 1000 miles driving, and remember they're not fully setup etc.

Haha, I cant link it cause it wont work, but go on...

http://www.visionplusuk.com/ and search k&n...thats where I got my coilover socks from too, guy at work does autograss and its his sisters shop i think.

and i could drill the end and put a cold air feed, but that would bypass the filter then lol. I'm thinking what to do tbh

I'd fabricate some aluminium (bent) to replace the filter, and run a cold air feed hose into one end of it..

So does it matter if the brass tubes are covered up? I'm thinking of a plate to go over the back of mine that holds the trumpets in place and cover the tubes, and then filtering the air at the bottom of the trumpet (cotton, foam whatever) so I can keep the look of the trumpets, but still filter the air.

If the tubes need to be covered, I may make a thin sandwich plate simile to the above but with holes or the tubes, with a filter in the middle (again, foam, cotton etc)

They do need to breathe freely and yes, in my opinion, they do need protection from dirty air. You wouldn't want them getting blocked..

harris's setup (old and new) does the job in hand perfectly as does mine..

my old one doesnt as the filters didnt cover the brass tubes, the guys above do as they seat on the little stacks like i have.

you need to cover the air jets and IMO they need to be in the same space for the same pressure.

you can block up the secondary air jet which will richen it up...all carbs are different, i have 3 sets of CBR 600 carbs form similar years...all totally different jets/needles/springs, thats why you cant take peoples setups as gospel.....sander_beer is running 135 main jets on 900cc carbs, yet me with a similar engine is running 170's on 600cc carbs lol

Ah I see now, I thought the cone filters went over the stack, I see now they go over the trumpet. If you get larger ID filters they would be ok though?

Yeah I'd imagine so mate!

I got filter socks originally and they were gonna be awkward to fit so didn't bother.

I then bought the cones a bit blindly, then they started falling apart and id read they can cause issues with setup so I just got the airbox...I got it cause was chatting to a few people with kitcar/racing experience using bike carbs and they said these are really good at keeping shit out (autograss) so ideal for road use, and the foam ones CAN have issues with catching fire and stuff (bare in mid they probably run richer as they're ragging the fuck out of them)

Ok airbox was £100 and it's annoying how it's offset, but I think it does the job ok, bonnet is closed most the time so looks don't really matter, it also still sounds good & you can buy replacement filters and back plates etc.

At the other end of the scale, carb conversion we're doing on my mates car the trumpets sit about 5mm off the bonnet so other than tights I'm not sure what to use haha :p

Cool. Dont really want an air box, form over function and all

Harris, how are your brass tubes open here

I was thinking tights or something equally fine stretched across my set up. Can buy replacements too, just like your filter!

because the gap between the trumpet and the plastic stack thing has a gap behind it to allow them to breathe, trust me i wouldnt like to you son :)

carbs are upsidedown in pic BTW

Theres a space all the way around the trumpet, inside the stack