No start bike acting weird

Hey guys well bike has been acting weird lately its an 83 xj750 mid maxim with around 24k miles on it. Just got a brand new fully charged agm battery put in it model yb9b off battery mart and 4 new plugs gapped to spec with my gapper. Bike has fresh gas in it and all the wires from inside the headlight to the rear are connected and grounded including the starter. I have tried starting the bike numerous times to no avail and it has been acting weird as though it is an electrical problem almost i feel because the rpm gauge jumps and pegs sometimes and comes back down when starting or if you hit the horn button it will jump randomly also. Not sure what else to try i have even tried a jumper box i have to make sure it wasnt a battery issue at all. Fuses also all are together working so i have no idea now.

 

Make sure your connections are clean and solid- battery, ground, starter, etc. Then go through this:
http://www.xjbikes.com/forums/threads/how-to-test-your-starter-circuit.7828/

I found that the negative cable (attached to motor) from the battery was greatly corroded and APPEARS to be what gave me starting fits. Unless the gremlins are in hiding . . . .

Anyhow, start with this, and in no time some of the really smart 'lectricity gurus will give you even better advice.

 

Okay thanks i also tried bump starting it several times to no avail though aka going around the starter to start the bike up and it still wasnt starting.