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Discussion Starter #1
Long shot but worth a try. Looking for anyone with a similar set up so I can tune this bike in.
2014 vstar 950. Very Short drags, modified the stock air box for more flow. I have the cobra fi2000 fuel management on there. Just looking for a starting point.
Right now my first pod is at 2.5- which seems pretty standard for everyone. Its pod 2 and 3 that i need to get. Ive seen people post as low as 3/3 and as high as 7/8. But nobody really has a set up like mine.
It runs good, great acceleration and power. Just ALOT of popping and backfiring through exhaust on decel

Thanks
 

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you don't say what your 2 and 3 settings are currently at, but those are mostly when you're giving the bike heavy-max throttle. the first setting, as the instructions note, control fuel delivery from idle up to 5000rpm. as i understand it, deceleration fuel would mostly be determined from this first pot setting. so i would recommend lowering that some.


 

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Discussion Starter #3
you don't say what your 2 and 3 settings are currently at, but those are mostly when you're giving the bike heavy-max throttle. the first setting, as the instructions note, control fuel delivery from idle up to 5000rpm. as i understand it, deceleration fuel would mostly be determined from this first pot setting. so i would recommend lowering that some.


Right now they are at 5/5

I really havent had a chance to put any miles on it since install
 

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i'd say all your settings are too high. even modified, the stock air intake system is still pretty restrictive and isn't letting that much air into your engine so you don't need a whole lot of extra fuel.
 

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Discussion Starter #5
I always thought backfiring through the exhaust indicated a lean condition though?
 

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What Causes Backfire?
When the engine on your motorcycle has an emission system malfunction, such as an exhaust leak or a moment of running rich or running lean, backfire can occur.

When an engine is running rich, there is more fuel present than there is air. When an engine is running lean, there is more air than there is fuel. In either case, the result is an incomplete combustion where the fuel is ignited by the heat of the exhaust, causing the loud, popping noise.

The stock muffler that comes on a motorcycle is designed specifically to ensure the complete and proper operation of the engine. When an exhaust pipe is changed, this causes an unbalanced air-to-fuel ratio. The airflow into the motorcycle is increased because of the difference in pipe design and other specifics. This difference causes backfire in the exhaust.

Other causes of backfire are bad or weak fuel pumps, low fuel pressure, or clogged fuel filters. All three of these issues have a direct effect on the air-to-fuel ratio.

Tips to Prevent Backfire
There are multiple ways to stop a bike from backfiring that vary from inspecting and properly maintaining certain parts of a chopper to adding or replacing specific fluids.

Check Your Carburetor
Fuel can not flow properly through a dirty carburetor; this will cause a lean-running engine. If the carburetor is dirty, clean it with a high grade carburetor cleaner.

Check Your Jets
Jets clogged with debris can also prevent fuel from getting through the engine properly. If this is the case, your engine will run lean.

Add Fuel Injector Cleaner
If your motorcycle is fuel injected, using a high grade cleaner will help remove the dirt and debris trapped in your fuel lines. Consult your motorcycle's owner's manual for usage of a fuel injector cleaner for your model.

Change Fuel Grade
A low-rated fuel in your motorcycle can also contribute to dirty or clogged lines. A higher grade fuel can help to clear fuel lines and keep your fuel tank clean.
 
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