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Discussion Starter #1
Can I use Pod filters on the stock CV carbs on my GS400?
I have heard that the carbs need a restrictive airbox to work properly so I figured I would check here first before messing with anything. Jetting carbs is not an issue for me.

Hey someone pas me the wrench........ Ahh screw it where is the torch
 

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CV carbs need vacuum to operate correctly. Pods don't provide the proper vacuum. Your bike will mostly run worse with the pods because the slides won't open all the way and the jetting would be all of the place. I would suggest getting direct lift carbs (normal carbs basically) and using pods with them. You can get more power and more throttle responce out of normal carbs than CVs. CVs were made to lower emissions (they run lean), provide better gas milage and are easier to ride which is a big plus to new riders or people using them for daily use.

22/m
1980 Honda CB750
1972 Oldsmobile 442
 

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Basically what Psycho told you is not true.All carbs need a vacuum to operate. It has something to do with physics, oh yeah, the venturi effect. That drawsw the fuel out of the float bowl, through the jets and into the carb venturi(clever name)where it atomizes and mixes with the air.
CV carbs operate on a pressure differential between both sides of the slide diaphram. The only effect the airbox has is to provide one side of that differential. If you are running pods you will need to rejet.Power is based on airflow through the carb and the CVs have an extra butterfly that does restrict airflow compared to a non-cv of the same bore diameter. As far as throttle response goes a properly set up CV is virtually identical to a non-cv except you don't have to fight a strong throttle return spring. If the slide is not lifting up all the way at full throttle then there is a problem with the set-up. It is possible to pull the butterfly over center at full throttle and restrict your flow, but that is a setup issue not a design flaw. Finally, CV carbs are not set up to be lean because they are CVs, it is because of emmissions and they will need to have a larger jet, although I have had the opposite happen, too. My XJ550 Seca race bike needed to have the mainjets leaned out after removal of the airbox.
If you have a modified engine and exhaust then going with bigger carbs of any type will allow you to get more HP. In that case non-cvs are easier to buy new, mount and dial in from a baseline.

Of course all of us running CV carbs on our racebikes might be wrong.


AHRMA 412
Vintage racing - old guys on old bikes
 

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im sorta with ken here. i had pods on my cb350 racebike for the first season. it ran fine but i couldnt keep them on the bike. i wanted some kind of an airfilter, but finally gave up.

and even if you run k&n's you may not need to rejet. every bike is a little different that way.

jc
 

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Discussion Starter #6
Ok Thanks guys. I was just asking because I have heard from other people the same thing Psyco said. I didn't think it would matter if I used pod filters either as I have run a bike with cv carbs without air filters before, however this was just to see if the bike started and I did not know how they would perform at higher throttle modulation.

Hey someone pas me the wrench........ Ahh screw it where is the torch
 

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with the carbs on my 750k i set the clip on the jet needle at the lowest (high set needle) position and installed #125 jets, runs great just a bit harder to start the colder the weather is, solved the problem by putting an electric blanket over the bike at night.

some people are like slinkies, basically useless but they still make me smile when i push them down the stairs
 
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