Hi.

The lever action at the end of the wire is twice the action of the carb... The throttle lever produces full throttle at half its movement range...

Any suggestions on products that gears down the action with a factor 2 (ie halfing the action of the wire or doubling the action of the carb?

or is the diy-route the only way? Fabricating some linkage lever or similar...

Some throttles have multiple positions to connect the cables. Carbs also may have more than one place to connect the cable