Hi Splash, A ‘70 Tiger would have come with AMAL
MKI. A round float bowl, with pressed in .017 pilot (idle) jet, behind mixture screw.
If you remove mixture screw, look in hole with flashlight you’ll see tiny brass bushing with .017 hole in it. Strip back some 18g stranded wire a few inches. Stick 1 strand into hole. You have to be steady as hole is tiny. This will push dirt into passageway. Shoot carb cleaner into hole & it usually will blow dirt back into float bowl. Remove drain from bowl first. Open fuel tap & let some fuel flush bowl.
A newer premier version Concentric
will have a cross head brass plug on opposite side of mixture screw. This brass is head of removable pilot jet. The very first version had removable pilot jet inside above float bowl. Highly unlikely you have earliest carb.
There is also new non premier Concentric
with silver cross head screw. It has pressed in jet. The silver cross head can be removed to make jet cleaning easier.
Lots of changes & carbs shaped the same.
has square bowl & looks Japanese like Honda carb. No tickler.
To check for worn out carb/slide bore, heat soak motor. Pull over & let motor idle 5-10 seconds. Open throttle slowly as possible. No matter how slow you open throttle motor should not falter or die. Some wear will falter, bad wear will die. This is tiny opening only .005” or so. You can pass the bad spot by opening more quickly, then motor will rev as expected. Don’t jump to conclusions. Do this test several times over a few rides. Cheating mixture about 1/4 lean (out with screw) will make idle feel worse, but improve dying somewhat. New carb is best cure. New slide may help temporarily.
Make sure idle is not too low in every case.
Street bikes tend to not like straight pipes. Not to mention peace of the island. Emgo repro original mufflers work well & not too costly. The motor is sensitive to air filter changes also. Paper elements can make make mixture do odd things.
Factory settings only work for factory stock bike & ‘70s fuel.
You have much going on at the same time. Will take some sorting to work this out.
Remember the basics start with good reliable power to both coils, good points & point wires to coils. Good condensers, good plug wires & good coils. Good advance unit & timing.
On paper it’s easy. Real life is lots of hard work, often frustrating if you don’t have experience.