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Nearing 40 hours. My engine is not totally dry. A couple of drops of oil leaks from the oil pump and is blown back on the filter. I think a push rod tube is also putting some oil on the right side of the case. Never the less, oil is getting on the paper element of the Aerovee supplied filter.
The result is loss of rpm. Take off last week resulted in 2780 static, increasing with air speed, to 2900 climb out. Normally 3000.
I removed the filter and did a run up to 2950 smooth. I know three other owners that have gone to a K & N, much larger filter and a reusable, cleanable, filter would be preferable. Along with the mixture needle problems to get max rpm, don't discount the possible loss of air at high rpm.

Onex wrote:I know three other owners that have gone to a K & N, much larger filter and a reusable, cleanable, filter would be preferable

FWIW ... on my previous Sonex I used the K&N E-3120 as a direct replacement for the stock filter. Now with my 3.0 Corvair I initially used a stock 4" paper filter but I get much better airflow using the same E3120 filter on this 120 HP engine as I did with the 80 HP Aerovee. I don't have any concerns with oil leaks. I don't know what the material is that is sent for the Aerovee pushrod tubes but the ones now used on all Corvair conversions are the Viton seals. Rubber tends to shrink with heat and leak where Viton seals will last much longer without leaking. The K&N filter is here:

http://www.amazon.com/dp/B00029WYW6/?tag=googhydr-20&hvadid=30945703821&hvpos=1t2&hvexid=&hvnetw=g&hvrand=5967016005904390038&hvpone=&hvptwo=&hvqmt=e&hvdev=c&ref=pd_sl_19wubv64g6_e

Dunno if this helps ...

Dale
N319WF

What does it mean, "can be cleaned". With compressed air? Gasoline? Solvent? Is it treated with a dust catcher? Do you retreat it after cleaning?

Here you go: http://www.knfilters.com/cleaning.htm

radfordc wrote:Here you go: http://www.knfilters.com/cleaning.htm

That's a great reference Charlie. On the two stroke engines we used to just rinse them in the two stoke oil and fuel mix, shake them out good, let them dry, and reinstall them. I haven't had to clean mine as yet but I'll buy the K&N Kit when I need to do that:

http://www.amazon.com/99-5000-Aerosol-Recharger-Filter-Service/dp/B00029WYEY/ref=sr_1_1?ie=UTF8&qid=1417980011&sr=8-1&keywords=k+and+n+air+filter+cleaner+kit

Mine stays clean for an incredibly long time but I fly from a paved runway mostly ...

Dale
N319WF

Dale, Rotax two strokes spit so much fuel/oil back out the carb throat that you don't really need to oil the filters at all.