Engine stalls when throttled

Very limited information for me to work with here, but if it is a newer fuel injected engine built prior to 2000 the try the procedure below.
Throttle Body Cleaning on vehicles without electronic throttle control (most 2000 and down)
You can in most cases repair this slow speed stall or unstable idle by cleaning the engine throttle valve and the idle speed control valve using a product called CRC Spray Throttle valve cleaner. Spray the cleaner into the air intake of the engine with the hose removed from the throttle body, the engine will try to stall so hold up the idle speed manually. Once you have used up about 1/2 can of the cleaner stall the engine out while spraying and turn the key off, disconnect the negative battery cable for 5 minutes and then reconnect and drive the car for a about 25 miles of varied driving modes. If this doesn't cure the problem you may need the fuel injectors professionally cleaned by the dealer service dept.

Hi Jimmy ! THE PROBLEM YOU ARE FACING MOSTLY IS ON THE THROTTLE BODY . IS GOOD IF YOU KNOW WHAT YOU WILL DO BY REMOVING THE THROTTLE BODY FROM THE ENGINE. JUST GIVE IT A GOOD CLEANING BY USING A CARBURRETOR CLEANER-CLEANING THE THROTTLE ITSELF AND ALSO IF YOU CAN CHECK THE IDLE SPEED CONTROL WHICH IS UNDER THE THROTTLE BODY ( ONE UNIT) STRIPPED BY FOUR SCREWS, CLEAN AND REFITTED.

Generally speaking, the common reasons for stalling are a faulty idle air control valve or a dirty throttle body.
The computer controls idle speed by how much air is allowed into the intake thru the throttle body.
Those two issues would be checked first.
Is the check engine light on when the engine is running ?

Common issue on this year and engine, Do the cleaning outlined below.

Throttle Body Cleaning

You can in most cases repair this slow speed stall or unstable idle by cleaning the engine throttle valve and the idle speed control valve using a product called CRC Spray Throttle valve cleaner. Spray the cleaner into the air intake of the engine with the hose removed from the throttle body, the engine will try to stall so hold up the idle speed manually. Once you have used up about 1/2 can of the cleaner stall the engine out while spraying and turn the key off, disconnect the negative battery cable for 5 minutes and then reconnect and drive the car for a about 25 miles of varied driving modes. If this doesn't cure the problem you may need the fuel injectors professionally cleaned by the dealer service dept.

check your fuel pump & filter.

This could be two things:
1. A stuck throttle grip. With the bike off and stopped, twist the grip and see if it snaps back into place. If it stops, but you can "push" it back into place - you have a stuck throttle. It's not idling. It's stuck "on".

2. Adjust the Idle. Typically, there is a little daisy wheel next to the throttle grip and you can turn it left / right to adjust the throttle.

turn the cable adjuster back to its original position ie between 600-700 rpm look to the left hand side of the carbs you will see a large adjusting screw on a metal bracket whilst engine is running turn inwards towards rear wheel until between 1000 - 1500 rpm remember to warm engine first as rpm will rise if idle is set with a cold engine as the engine warms up when riding

SOUNDS LIKE YOU ARE SUFFERING FUEL STARVATION TRY CLEANING OUT THE JETS.

use a thin piece of wire and clean the ilde port and transfer port if that doesn't clear it up check idle jet

does throttle sensor check out correctly???