750 starter spins, doesn't engage

My '83 xj750s starter spins but doesn't engage.

When I tap the starter it kicks the bike over once or twice but then just spins. I find my self having to continuously having to tap the starter multiple times until she fires. This only happens when warm tho. When cold I can crank and crank and crank.

Fixable problem or time for new starter?

 

New or rebuilt starter motor time, or starter motor rebuild kit. It sounds as though the brushes or commutator in the starter motor is giving up the ghost....

 

The starter motor is always engaged, it has a friction clutch.

 

It can be the battery not kicking it over fast enough. That is an easy test. Put jump start cables from a car to the battery .. and it will tell you.

But I'm betting it IS the starter motor.

 

Ummmm...

What OIL are you running? If it's an automotive or synthetic, it could also be oil-related since it only happens "warm."

 

It is not a battery issue I can assure you that. I figured its probably rebuild time but wasn't sure if there was a fix.

Fitz: I do have the correct motorcycle oil in it but just to be sure (and with it being spring) it is time for a change of oil anyways. Is it a possibility that if some fuel got past the floats over the winter and got in with the oil that would cause it? I show no signs of that happening, but we will see when I change the oil. Let you know how it goes....

Chacal: sorry, I blew over the write-up you have on your parts list. Just went through a second time and saw it. Will follow that process.

 

Thanks guys. This has been happening on mine too.

What about if the start button operates intermittently? Sometimes when I push it...it works perfect. Sometimes it doesn't work at all...until I wait a second, try it again and then it works fine.

 

Before you get too far into it, ...

Pull the Starter
Visually inspect the Brushes and Commutator.

Brushes too short, ... Intermittent.

Carbon Dust built-up on the Commutator, Brushes and Housing will contribute to causing the Starter to fail to operate.

 

Check the earth wire from the battery to the frame then to the engine is ok and that the connections are clean,

 

When you press the button & it DOESN'T work, does the oil lamp still light up? If not it could be the button/wiring. If it does, then the above, plus check out the safety circuits/relays...

 

If the starter spins but does not turn the engine why rebuild it?. Sounds like starter clutch.

 

Because if it doesn't spin fast enough it won't cause the starter clutch to engage.

 

just make sure the daggone thing isnt spinning backwards.

 

Update:
I was having some misfire issues. I pulled the plugs to find they were caked with carbon buildup. What caused that's another issue I need to figure out.

I bought new plugs since the old ones were oxidizing on the outside, I figured it was time anyways. This time when I pulled the boots from the plugs, the boot fell off the cable. This was obviously a factor in the misfire.

I fixed the boot and replaced the plugs. In the end, this fixed the starter issue. She will start perfectly 99% of the time. But seeing as 99% isn't 100. I will pull the starter to visually inspect and clean. I found this to be an odd solution. I forgot to mention all this was done before an oil change which I still have yet to do. That may bring it back to 100% working order.