Triumph Repair: 69 Triumph 650, gasket leaks, triumph 650

Question
I was given a old custom chopper with a 69 Triumph 650 motor in it with an aftermarket single carb put on in the 90s.  It was last riden about 3 years ago, I replaced plugs aircleaner battery and some wireing.  It will start on the first kick and idle ok for a cupple seconds then it will start to rev up untill i shut it down because its reving to high. The throttle cable moves freely so i dont know if it is somthing simple or i need to rebuild the carb, any ideas would help me alot.

Thanks
Brandon

Answer
Hi Brandon,
A basic fact is that no engine can raise in RPM unless it receives extra air and fuel so you need to Remove and go through the carburetor and note what brand it is. Also since you said it has a single carburetor then you have a 650 with the two intake ports on the head side by side facing straight to the rear not what they called a "Splayed Ported" head that had each of two carburetors out at an angle, correct?
Also look at the intake manifold to head for gasket leaks.
let me know what brand carb it is.
Howard