Harley Davidson WL recommendation for air filter

[epazikas]

Hi,
I would like to raise a question to our WL community if regards to which air filter would you recommend for the Harley Davidson WL models, i.e. the original or the high performance K&N air filters?
My concern is more related that back fire may occur out of the air cleaner when starting a motorcycle that is either flooded or standing still for a long time. I believe that the paper made is not a good option because it can get fire in quite easier than the metal one.
Any comments?
Thank you!
Ed

[Architect]

I run a stock setup, but was thinking about stepping up to a K&N or similar. I too am interested in what others have to say on this topic.

[1937EL]

I run a stock setup, but was thinking about stepping up to a K&N or similar. I too am interested in what others have to say on this topic.

I couldn't get a K&N filter in my round 7" J-slot filter housing, due to the thickness of these filters.
It is however possible to use a K&N filter in the later type 7" filter housings, that are using a screw in the middle to mount the cover.

[sswaney]

These work in the J-slot type
https://www.jerrygreersengineering.c...string=JG-2922

[epazikas]

K&N versus regular air filter

Hi, making the K&N to fit the air filter cover is not an issue, see the adjustment I did in the pictures attached, however this is made of paper and plastic, with some metal. It can happen that the motorcycle back fires and a flame can, if the bike is flooded, come out through the air filter. It happened to me couple of times and then there was a small flame that I could easily extinguish with my hands.
How dangerous is it to have the K&N filter in this case?
Is it recommended?
Thanks for your comments, Ed

[T. Cotten]

Fix the backfire first, Ed!

(And then go with the electrostatic 'brillo' anyway.)

....Cotten

[epazikas]

Fix the backfire first, Ed!

(And then go with the electrostatic 'brillo' anyway.)

....Cotten

Hi, I would like to get tips on how to fix it, if possible? This backfire sometimes is caused after my motorcycle is standing on the garage for a long time, then, as a start, I do kick it like ten times with ignition off, just to circulate the oil around. After that, fuel ON, choke fully OPEN, throttle advanced and spark retarded. When I switch on the bike and get the kirst kick, then sometimes this flame pops up. Probably caused due to excessive fuel that is injected?
Am I wrong? Thanks for some comments, Ed

[T. Cotten]

Well Ed,

Assuming all of the usual things are in order, such as ignition, valve adjustment, etc.,
then two things immediately come to mind.

Your petcock is probably seeping, and you also may have a small but dangerous vacuum leak.

Please disconnect your fuel line and watch for insidiously slow drips. Fixing petcocks has been discussed previously.

And so have vacuum leaks of course. To eliminate the variable, please review http://virtualindian.org/11techleaktest.html.
If you don't get bubbles, we haven't found the problem.

....Cotten

[Architect]

These work in the J-slot type
https://www.jerrygreersengineering.c...string=JG-2922

That there seems to be the answer, thanks for the link.

[Jerry Wieland]

The are more than a few reasons for backfire when starting a bike utilizing a Linkert carburetor as Cotton has mentioned a few. From my experience most of them occur when someone starting a bike has both the choke plate and the throttle plate wide open at the same time. This is a no-no on a Linkert. It causes a severe lean condition prone to creating fires.

Jerry

Hi,

My concern is more related that back fire may occur out of the air cleaner when starting a motorcycle that is either flooded or standing still for a long time...

Thank you!
Ed

[T. Cotten]

The are more than a few reasons for backfire when starting a bike utilizing a Linkert carburetor as Cotton has mentioned a few. From my experience most of them occur when someone starting a bike has both the choke plate and the throttle plate wide open at the same time. This is a no-no on a Linkert. It causes a severe lean condition prone to creating fires.

Jerry

I'll agree with 'operator error', Jerry!

(Although I don't know how to start with the choke closed.)

An indecisive kick can make it go 'poo-hah', too, so air cleaners are important spark arrestors.
Fuel mist certainly reverts out the mouth of the carb, and P4gas eats many modern elements, burnt or not.

I bought one for an Onan motor that fit, but the bike wouldn't start.
A Geoff Ringle K&N in my inventory makes me think restriction would at least require re-tuning.

....Cotten

[duffeycycles]

My theory is if you have to retune for a restricted air filter ,you should rethink using that air filter.

[T. Cotten]

My theory is if you have to retune for a restricted air filter ,you should rethink using that air filter.

That's why mine's for sale, Duffey!

New in the box.

....Cotten

[41craig]

My '41 ULH backfired and caught fire in 1973. I had the OEM filter in it. My problem was that I couldn't find a good OEM air cleaner cover at the time and used an aftermarket cover. That cover did not have the drain hole in the bottom. The gas gathered in the bottom of the air cleaner due to the Side Valve carb. coming out on the kickstand side of the bike. One backfire and up in flames. If you have an aftermarket air cleaner, without the hole in the bottom, cut a hole in the bottom like OEM cleaner.
Craigimage0-006.jpg

[T. Cotten]

My '41 ULH backfired and caught fire in 1973. I had the OEM filter in it. My problem was that I couldn't find a good OEM air cleaner cover at the time and used an aftermarket cover. That cover did not have the drain hole in the bottom. The gas gathered in the bottom of the air cleaner due to the Side Valve carb. coming out on the kickstand side of the bike. One backfire and up in flames. If you have an aftermarket air cleaner, without the hole in the bottom, cut a hole in the bottom like OEM cleaner.
Craig

Historic bummer, Craig!

It narrows the problem down to backfire out the carb.

Drool happens; Your Flatty should have been lucky the puke didn't just go down into the cylinders like an OHV.

....Cotten