New member intro '77 kz650 starter clutch

Hi all... new member here with my first own kz.  I rode my brother's '76 kz650  45 years ago  and this '77 popped up on the market so I had to buy it even tho I probably won't keep it with my '79gs1k. It looks to be in good shape and "only needed a little carb tuning.  I replaced the starter solenoid and cleaned the starter and almost done with the carbs.  I'll search and post the technical sections but instructions here say introduce and ask a question.. so does that look like the correct  spring for the fill side of the accel pump?  And starter clutch mine was making a racket when the motor  shut down.  I suspected it was always engaged but with starter out the gear freespins one way (seems right).  So when this motor shuts down does the starter briefly come in for a puff of spin?  I know that sounds crazy but when my zrx shuts down I hear a brief spin down.   

garyS wrote:

Hi all... new member here with my first own kz.  I rode my brother's '76 kz650  45 years ago  and this '77 popped up on the market so I had to buy it even tho I probably won't keep it with my '79gs1k. It looks to be in good shape and "only needed a little carb tuning.  I replaced the starter solenoid and cleaned the starter and almost done with the carbs.  I'll search and post the technical sections but instructions here say introduce and ask a question.. so does that look like the correct  spring for the fill side of the accel pump?  And starter clutch mine was making a racket when the motor  shut down.  I suspected it was always engaged but with starter out the gear freespins one way (seems right).  So when this motor shuts down does the starter briefly come in for a puff of spin?  I know that sounds crazy but when my zrx shuts down I hear a brief spin down. 

NO - any time the motor drives the starter you risk exploding the commutator in the starter motor. It's possible if the clutch basket and starter clutch cush-drive rubbers are worn that there may be some "chatter" when shutting down. I suspect what you hear on the ZRX is the alternator spinning down (I don't know if it has a "freewheel" drive set up)

garyS wrote:

Hi all... new member here with my first own kz.  I rode my brother's '76 kz650  45 years ago  and this '77 popped up on the market so I had to buy it even tho I probably won't keep it with my '79gs1k. It looks to be in good shape and "only needed a little carb tuning.  I replaced the starter solenoid and cleaned the starter and almost done with the carbs.  I'll search and post the technical sections but instructions here say introduce and ask a question.. so does that look like the correct  spring for the fill side of the accel pump?  And starter clutch mine was making a racket when the motor  shut down.  I suspected it was always engaged but with starter out the gear freespins one way (seems right).  So when this motor shuts down does the starter briefly come in for a puff of spin?  I know that sounds crazy but when my zrx shuts down I hear a brief spin down. 

What Wookie said
Spring looks right.
Here's a diagram link for the secondary shaft upon which the starter clutch resides.  If your starter is starting the engine, the starter-clutch is probably working okay.  If you have to replace any of these items, it is a PITA as you likely will need to take the engine out and split the cases to get to the inner parts.  Not all of them are accessible from the outside.  The KZ650s and 750s with same configuration (Also 650/750 Yamahas of the same era) drive the crank from a jack-shaft instead of the end of the crank like z-1, KZ900 and 1000s.  

www.kawasaki.com/en-us/owner-center/parts/143079/1979/KZ650-C3

Hope this helps!
Bobf

Having restored about 20 650's over the years here's my 2 peneth worth.
No, the starter shouldn't and can't engage on shut down. 
"IF" you decide to replace it ensure you replace the whole unit and starter gear NOT just use the springs and rollers repair "kit" unless you want to do it again in short order. 
The whole job can easily but fiddlely done from underneath without removing the engine. 
Remove the sump pan and clutch basket plus a few retaining plates and the shaft can slide out allowing removal of both the starter clutch and gear. Your hardest job is the clutch basket hub nut which is torque to 130 ftlb. 
Before removal check the primary chain free play. The service limit is 27mm.
Heres a picture of a new and worn starter gear for reference. 
 
 

Warren3200gt wrote:

Having restored about 20 650's over the years here's my 2 peneth worth.
.........
The whole job can easily but fiddlely done from underneath without removing the engine. 
Remove the sump pan and clutch basket plus a few retaining plates and the shaft can slide out allowing removal of both the starter clutch and gear. Your hardest job is the clutch basket hub nut which is torque to 130 ftlb. 
Before removal check the primary chain free play. The service limit is 27mm.
 

Much thanks for your insight!!!  Learn something new every time I come on this forum.  Now I feel like finding a used KZ650 "....starter doesn't work....." to try this out!  I wasn't as innovative back in the day and could have saved much time if I'd only.....   20/20 hind sight!!  

 

That photo showing a NEW vs USED starter clutch gear has been posted here countless times.  Thing is, I've never seen a NEW gear, other than when it came out of the OEM packaging.  After a short time in the vehicle, they all look like the USED gear, and most function just fine.  

Nessism wrote:

That photo showing a NEW vs USED starter clutch gear has been posted here countless times.  Thing is, I've never seen a NEW gear, other than when it came out of the OEM packaging.  After a short time in the vehicle, they all look like the USED gear, and most function just fine.  

The starter clutch and starter gear wear together as a pair. Yes, you can just replace the starter clutch but a worn starter gear will prematurely wear your new starter clutch.
Much the same as a new final drive chain on worn sprockets will reduce chain life and vice versa. They need to be replaced as a set. 
It all depends if you want to do the job properly or on the cheap at the expense of longevity. 

Welcome Gary.

Nice project you've found.