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Pod filters on F650?

tri650

New member
I have a 99 F650 Funduro and want to ditch the airbox and go with pod filters if possible. Rubber boots are shot and the air box is a lot of empty space. Have searched on other sites, forums, etc., and can't find anyone with direct experience of ditching airbox and just attaching some type of pod filters. Would require building some type of protection from water but would rather fabricate something than deal with the current hunk of plastic that takes up a lot of space. Anyone?
 
I have a 99 F650 Funduro and want to ditch the airbox and go with pod filters if possible. Rubber boots are shot and the air box is a lot of empty space. Have searched on other sites, forums, etc., and can't find anyone with direct experience of ditching airbox and just attaching some type of pod filters. Would require building some type of protection from water but would rather fabricate something than deal with the current hunk of plastic that takes up a lot of space. Anyone?

It will also alter the intake air flow to the extent that re-jetting the carburetor will most likely be required. Not big deal if you have access to an exhaust gas analyzer. A dyno run or two might be fun too.
 
I realize this is an old post but thought I'd post my thoughts & experience for future readers. The bike will run better with the stock air box than with pods. Stock air boxes often have velocity stacks inside the box, to help create a better airflow into the throat of the carb or F/I, which results in a better mixture with the gas. This system needs an area of still air to operate properly and efficiently over a broad RPM range. Pods require the intake to suck its air and don't have the velocity stacks to aid in the air/fuel mixture turbulence. Engines are much less tolerant of intake changes than exhaust changes.

Don't equate the intake noise with more power. There may be cases in racing where you might be able to tune a pod over a very narrow rpm band, but it would suffer at other areas. Not what you want for a street bike.

My 95 Airhead and my 86 K100 both have a fairly large air box and velocity stacks are located at the intake area of both bikes. Over the years much has been written about snorkle lengths/sizes on the airheads air box affecting performance and at one point BMW came out with a solution of drilling some holes in one of the snorkles. Just changing one snorkle for a smaller or bigger one would cause running issues. My memory is a little foggy on this but I also remember reading about using GS intakes and so on in the non GS oilheads.

So tread careful,you could be going down a rabbit hole. Turning carbs, rejetting, needle positions etc can get complicated and one tends to just move the problem area around. The engineers got the A/F ratio pretty close on our bikes and the one thing that does affect both carb & FI bikes is altitude. But that goes away when you go down the other side of the mountain. So my thoughts for a street bike is to leave it stock, unless you have to rejet for altitude.
 
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