81 ltd 750 wont turn over

so i posted before and getting discouraged ....my bike wont turn over brand new battery ,tested starter it works.brand new solenoid.it would turn over before now get nothing .......checked all the connections im thinking ill just sell it

It may be something fairly simple. Have you considered simply taking it to a shop and letting a pro diagnose the problem? Ed

Can you turn the engine over by hand (with a wrench)? Does it do nothing at all? Finally, does it have a kickstarter?

Does it turn over if you breach the solenoid poles?

Assuming the motorcycle is a KZ750-H2 4-cylinder, it shouldn't have a kick-starter (unless someone installed one).
When pressing the start button, does the starter solenoid click or anything?

I would check the battery with a digital multimeter & do a load test. Never assume a battery is good >> test it. New batteries are known to be bad or go bad if not properly serviced before installing it. If the battery checks out after charging with a good motorcycle smart charger, then I'd test for voltage at the starter solenoid. If you're getting voltage at the fat starter cable, then I'd make sure the connection is good at the other end of the fat cable, at the starter.
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