1978 kz650 starter

I changed my oil this week and installed new battery, now when I hit the starter button it makes a whiiny grinding sound and wont start till i keep pushing over and over again. I put walmart brand 10w40 in (supertech) in this time and was wondering if the oil could effect the starting.

If you look at the label on the oil container I believe you will see the oil is NOT JASO-MA compliant. As a result, it may contain friction modifiers that should never be used in a motorcycle. You may want to try changing the oil and this time use the correct oil rather than oil intended to be used in automobile gasoline engines.

The sound when you operate the starter is very likely the starter clutch slipping. If so, the solution is to use the kickstarter or to replace the starter clutch parts. See ....

www.kzrider.com/forum/2-engine/593654-st...ch-kz750-1980#630265

kickstarter not functional. I know you say oil is not good for bike but would that make the starter clutch slip more.

I'd try changing it to Valvoline bike oil or Rottella 10/40 or 15/40 and maybe pray ...... I changed mine to Mobil4T bike oil and the starter clutch started acting up on the first start after..... I think in my case it was just time but reg Valvoline bike oil fixed it for the rest of the summer but then came back in the fall when things really cooled off and the cranking of the motor was harder......... do a search here too tons of info on it and parts are not avaliable just anywhere anymore.