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Oh yeah I have a 1981 2 z 440 belt drive and I am meet in my first Cafe racer build I need to know the jet in sequence for the pods filters with open exhaust?
Or can I get some opinions on which exhaust to use.
 

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Open exhaust is and open exhaust and that won't be your problem, with pod filters directly fitted to CV carbs on a twin cylinder bike, the CV carburetors will be your problem. Vacuum operated carburetors simply do not work well with the setup you described, never have, never will. Anybody that tells you otherwise, ask them how many races they have won, or even just show us a dyno chart for that bike.
 

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Why don't CV carbs work with pods and open exhausts?
Before I found this out I fitted pods and straight through mufflers to a KLR650 and an XS 750 and they worked really well, just had to make sure I used pods that didn't block the air holes at the front of the carbs. Block those up and they don't work.
And I don't win races because I'm too old and slow and don't have dyno charts as I only use the trusty butt dyno.
 

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Why don't CV carbs work with pods and open exhausts?
Before I found this out I fitted pods and straight through mufflers to a KLR650 and an XS 750 and they worked really well, just had to make sure I used pods that didn't block the air holes at the front of the carbs. Block those up and they don't work.
And I don't win races because I'm too old and slow and don't have dyno charts as I only use the trusty butt dyno.
It does work, oem carbs just arent tuned for open intakes, and parts are harder to find than for proprietary keihin or mikunis for example. There will probably not be needles available with the taper necessary for running pod filters successfully on your bike though. And cv carbs benefit from straight intake runners between carb and filter. About 2-3" is enough. If you dont have a clue what im saying here, give up, dont mess with it, run the stock airbox instead.
 

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And cv carbs benefit from straight intake runners between carb and filter. About 2-3" is enough.
That would be it, in order to get the filter onto the KLR it had a 50mm runner, the xs750 had 20mm runners, and I used 100mm long Unifilters, I guess the length of them had an effect like a runner as well.
 

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Why don't CV carbs work with pods and open exhausts?
Before I found this out I fitted pods and straight through mufflers to a KLR650 and an XS 750 and they worked really well, just had to make sure I used pods that didn't block the air holes at the front of the carbs. Block those up and they don't work.
And I don't win races because I'm too old and slow and don't have dyno charts as I only use the trusty butt dyno.
Constant velocity carburetors came about as a means to reduce fuel consumption and exhaust emissions. They are designed to run as lean as possible, that is how the design came about, it is literally a pollution control device. People who say they run great with open exhaust and pod filters always bracket that claim with they don't race and don't dyno test anything, they go by noise and vibration to determine performance and don't give a shite if the thing has a great flat spot in the power curve, stalls returning to idle or spews raw fuel from every orifice.

KLR is a single, you don't need to balance 2 carburetors on most single cylinder engines. Balancing a bank of CV carbs fitted with pod filters and open headers is :/ well good luck with that, you'll never get it anywhere near as good as the factory did. Dyno testing or track proven performance is proof of a motors performance, anything else is make believe.
 

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i've done 38mm mikuni cv on ducati with open exhaust and pods. you can get jet kits for them, but the closer you get a cv to the response and performance of a slide carb the more their inherent performance limitations become apparant.

i'd put as long a ram tube on the end of the crb that you can (enclosing any carb air feeds), then put some sort of good filter on the end of it.
 
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