OK try cleaning the carb and its jets like I said be careful to not loose any springs out of them or reinstall in the wrong location. Look in the carb, you should have a blue tube sticking out into the venturi. When cleaning the main jet in the bottom should be a brown jet. If not this jet can be drilled to .040 same as a brown one. Be sure both carbs are the same. NOW keep in mind the Indians tend to pop and run rough one one cylinder when cold or havn't been started in a while. They simply hate to run cold. And idling one always tends to be a bit leaner acting. How does it rev once hot and run once wrmed up. I am talking running for at least 5 to 10 minutes. Warm. If you have Jon Jon's Old mower It was always very cold natured. Fact if I remeber right it doesn't even have the bigger carb's on it. You should put a set of ohv 17 hp carbs on it. Then you will see one heck of a difference. Again you need the blue tube and brown jets or drill the jet to .040. Get with Troy Larsen there in Printice, he is my team mate and he too runs a tvt-691. He can help alot also. Will get you the numbers for the carbs all my notes are at work.