Kawasaki Sportsbike Riders Club - Australia - Online Forum

Okay so yesterday I took the left hand engine cover off to fix an oil leak. Didnt disconnect any of the wires etc from the cover (magneto etc) and just left it hanging there while I fixed the problem area with some instant gasket (great stuff btw).

Anyway there is one loose gear that slides off the shaft attached to the cover, it can only go on one way so I didnt think anything of it when putting it back together. Anyway I get it all back together sweet and I go to start it...

It starts fine like always, yet the starter motor doesnt seem to cut out once its started. Its like the gear continues to spin and make a real high pitched whirl kind of sound for a second or two before it stops. Now there is no clashing of gears while this is happening so its not like any gears are mis-aligned. And now I find that once the motor is running, I can actually hit the starter button and it whirls away.

Im fairly damn sure it didnt use to work when the motor was running. This makes me think its an electrical problem. Does that sound right? If it was a mechanical stuff up I still shouldnt be able to hit the starter while its already running I would have thought?

How does a starter motor actually work? What normally stops it from spinning once the engine has started? Have I somehow put the loose gear back in wrong?

Ive ridden it to work and back (~100km) and its running better then ever, the only reason I even noticed the problem was because of the whirring sound after it starts.

Anyone got any bright ideas? Its a 98 ZX9R.

Without realy seeing it its hard to realy say.
If the only thing thats different from how it was before you fixed it is the instant gasket then that would be the first thing that I would relook at,
does the thinkness of the now gone original gasket give extra clearance that is now gone ??
or the gear you replaced realy on the right way or/and is it still as free
wheeling as it was before I removed it ? has gasket goo fallen on to it ?

If you reopen the cover you should be able to see some type of wear or rub marks

barring an electrical fault, theres not a lot that can cause the starter to keep going. the starter engages a spragg (one way) clutch that by design allows the starter to turn the crank, but stops the crank turning the starter. This might have gotten slightly caught. see if the noise continues, and if it does, do the screwdriver stethoscope method to see whereabouts precisely the noise is coming from.

clearance issue? honestly i douby it, surely they'd need to give more allowance than 1 mm to the end casings. But give it a shot, i could be wrong

Hrmmmf

Does anyone know if there is a spring or anything that presses against that loose gear? Cant say I saw one but stranger things have happened.

NinjaMoses wrote:It starts fine like always, yet the starter motor doesnt seem to cut out once its started. Its like the gear continues to spin and make a real high pitched whirl kind of sound for a second or two before it stops. .

Check the starter switch up on the H-bar, it's not jamming a bit is it?

i hate starter motors...the one in our car just went...$300 later and its replaced What happened with ours sound kinda similar to your problem. I started the car one morning to head off to work, started fine, sounded a little noiser than usual so I didnt think twice...until I tried to drive, it was like the brakes were locked on, and the brake light was showing...turn car around and drive the 50m trip home, turn off the car and it doesnt stop I could take the keys out and everything, put car into gear and still would stop. That had happened was the solinoid had stuck on and the electrical contacts to the starter were connected all the time....5 mins of a starter motor going tends to totally fry them. I would imagine bike starters would work in a similar fashion to a car so I would check to see if the starter is losing power once you take your finger off the 'go' button.

Found a workshop manual online for it.... here is the page that deals with the starter motor etc.

I have circled in red the loose gear... as you can see no other springs/washers/spacers....
*sigh*

wazza1234 wrote:i hate starter motors....

I bet if ya had to crank ur car/bike over by hand you wouldn't say that

NinjaMoses wrote:..... What normally stops it from spinning once the engine has started? Have I somehow put the loose gear back in wrong?

the starter clutch is what stops it from spinning, once the engine has been started. The small gear that you replaced meshes with the larger gear, which is on the starter clutch.

The starter motor will work when the engine is running, its just that you have probably never hit the starter switch while the engine has been running, and have therefore never heard the sound before ?? (only a guess)

You *may* need to check the alignment of the starter gear and the starter clutch gear, although this should be fine if you have not been having any problems with starting the bike. Its when the starter motor 'jams' on that you will need to fully disassemble and fix.

When you used to start the bike, did you have your helmet on first ? and when you noticed this new sound, did you have your helmet on or off........? It could be this simple - the bike has always made the same noise, but you are only noticing it now for the first time.....just a thought.

I don't think you have too much to worry about.