I have a 1971 suzuki ts 125 and I can't seem to

You'd be best off buying a service manual from say amazon for $20-25 bucks. It'll be yours to keep and offer thorough procedures. Best money you'll ever spend.

check the ht lead has not split

If your talking about air fuel mixture screw a good place to start is turn screw clockwise till stops.back out 1 1/2 turns get bike running see how throttle responce is.If bike is still sluggish then try 1/2 turn increaments counterclock wise till bike runs smooth.Good luck ...Brian

Yes, every carburator hase idle screw. Turn it to left tu turn down the idle.

Clean your carb and replace your spark plug that should fix the problem.

Hi and welcome to FixYa,

Initially, check for pulsating voltage on the black/yellow wire from the magneto to the ignition coil. Additionally, temporarily disconnect the black/yellow wire to the ignition switch.

Perhaps a wiring diagram would be of additional help.

Good luck and thank you for asking FixYa.

You would have to buy a service manual for that bike and the wiring diagram would be on the back page you might find some at ebay.com

is it getting fuel? try tipping a very small amount of fuel down rhe plug hole, replace the plug if it fires you have a carb problem.