oil or dry?

[twisted]

I have just received my new su carb air filter  from oz .
When I was reading up on it before I bought it people were saying that the filter foam that comes with it was not great ( could brake up if carb coughed fuel back on to it then suck it into the engine) and to use an after market foam. As it was going to be coming a long way I got said foam also.
The replacement foam comes in a sealed bag pre oiled.
Question is whats the difference and are there any benefits to one or the other?
Whats the oil for?
Cheers.

[markju]

Wouldn't know of any benefits re oiled or not but think the oil is there so particles of dirt get stuck to it. That's why they need cleaning and re oiling on a regular basis.

[Tony oily bike]

The oil on the foam is the 'filter' part, it lets air through but withholds the nasties. the foam is primarily a device to keep the oil in the right place.

By using the correct specific oil, and correct oil cleaner/remover along with the right cleaning & drying procedure, the system can be used & reused many many times.

One of the big uses for oiled-foam filters was in off-road vehicles where there was a lot of sand etc. An added benefit is the oil is also water resistant. (useful for filters exposed to the elements)

Proprietary manufacturers sell filter oils and cleaning solutions, and include instructions of how to apply/clean etc, so have a web search to see what's on offer. There's obviously an outlay for the kit, but it should last  for a fair while as normally the quantities used are quite small.

Most people have heard of K&N for aftermarket filters. They offer oiled filters, the most common being the meshed-encapsulated fluted design (large surface area), along with good quality oils and cleaning solutions.

http://www.knfilters.co.uk/default.aspx

Hope that helps

[twisted]

thank you gentlemen  i have fitted it now with the oiled foam. its a ramflo unit for a 1 1/4" carb. haven't seen one mounted on a trike so needed it 

 

oil or dry?

oil or dry?

[BikerGran]

Smart!

[Manky Monkey]

That's nice Craig.

[twisted]

Thanks to you both  . Just need to find somewhere to get the oil to re oil the filter foam in the future when I need to clean it.

[scannerzer]

you may need to change your needle for that hiflo filter but it will do a good job

cleaning kit

http://www.ebay.co.uk/itm/K-N-Recharger-Air-Filter-Cleaning-Kit-Cleaner-and-Oil-/301356956115?pt=UK_Motorcycle_Parts_13&hash=item462a4639d3

[twisted]

cheers scannerzer was looking for lynx filter oil (what the box recommended) but all i kept finding was oil filters 
what needle would i have to change to? just fitted a new aat one 

[fifer]

Have a look at my needle comparison spreadsheet ;

https://sites.google.com/site/fifersrelianthintsandtips/carb-su-carb-jet-needle-spring-type-comparison-of-4-common-needles

.
To check your mixture throughout the range you need to do a plug chop at each of the throttle openings / revs .
You will find out where it is running weaker or richer .

Since each trike is individual regarding exhaust / silencer / manifold modifications / gas flowing etc to get peak performance you need to get the needle stations correct for that trike .
Unless you go to a good garage with all the facilities to test that then the next best thing is to check by doing plug chops and seeing where the needle needs to be richer/weaker / .
If it is running rich at one section there is no easy way way to modify it because the needle is too thin at that point and would need something added to thicken it .
If it is running weak then that means that the needle is too thick at that point and a tiny , tiny , tiny bit can be removed from the needle to make it thinner to let more fuel flow past .
This of course takes a lot of time testing by fitting / removing / fitting the needle and trying it out on the road .
You might find a needle which nearly suits what you require from the list below .

List of other needles at ;

http://www.teglerizer.com/suneedledb/090needlesortjava2.htm

.
.

[twisted]

cheers guys. will look ans see what happens. she seems to be running ok at the mo

[ROD]

I understand why a needle change is reqd on pancake filters, but this one is oil impregnated, so should be on a par with a factory reliant filter, due to the oil being an extra barrier?

[Olds]

Think it's the other way round.
I could be wrong, but I feel the problem with the traditional pancake filters is the design. They tend to be very shallow, requiring the airflow to change direction in a confined space and the filter medium is also limited in surface area.
An oiled foam hi-flow filter should not be soaked in oil to the point that it restricts air flow.
The filter I fitted is small in diameter but quite deep. Seems to be a good compromise.
Never bothered changing the needle, as I'm not after maximum performance or economy and it is running fine. Possibly too rich at some  throttle setting or too lean at others, but not enough to notice.

[ROD]

Is that a home built filter casing olds? I was thinking of using a std reliant air filter, housed in a box which would sit aft of the carb with a large diam tube eg Rover sdi type, or similar connecting carb to the side of the box.
Sorry to spam your thread Craig.

[Olds]

No, I bought the filter element and case from ebay and made my own baseplate to suit the SU. Chosen partly for it's shape as it wouldn't hit my knee.
It's not just the filter element that affects the air-flow, but also the case design especially the diameter and length of the inlet pipe. Really wouldn't worry too much about this though, as you are not building a racer (or are you ?  ).