Welcome to the forum from north ms.
Specs say you have a 4.50 gallon tank and a single carb. What mods in particular did you make to the exhaust? I'm no mechanic, yet it appears you may need your carb rejetted since after the exhaust mod it's drinking a lot of fuel and puttin' on you. There's a lot more knowledgeable members on here than me, and I'm sure they'll chime in.
Glad you joined us, post some pics of your bike, and keep us updated. Be sure to ask your question in the vstar section as well. Ride safely!
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