1981 Kawasaki GPz550: Restoration

Great build

the guy says to call or leave a text but makes it difficult to find ph #. Hit the contact button and it shows up.

Not good at marketing

[cowboyup3371]

Found this one Steve - http://cincinnati.craigslist.org/mpo/4378716512.html

[srsupertrap]

I've got a complete extra airbox & boots if you decide to get away from pods -

Thank you for the offer Montanaman . . . I am currently inclined to stick with the Mikuni Flatslides just because the GPz was running with them before it went into stasis. Perhaps between the two of us we can make one whole 1981 GPz550. I agree these are money pits

Steve

Good progress, were you able to button up the motor yet? -

No, Kleeme Performance is done with cylinder head which needed a valve job, valve stems milled to get the valve lash back in spec, bolt weld repair, valve springs, stem seals, bead blast you get the idea. Tom is currently wrapping up his inspection of the cylinders. I am suppose to get an update this week along with the bill.

PS: I would appreciate everyone keeping an C/L eye out for 1981 GPz550 parts. My requests on the Gpz550 forum for a seat, rear fender, rear rotors etc have gone unanswered. My front M/C is dry so I am figuring that must be toast too.

I've got a complete extra airbox & boots if you decide to get away from pods -

[Big T]

Need more parts?

http://cleveland.craigslist.org/mcy/4379860884.html

Very little parts compatibility between the models

The 1981 is a one year only bike

Steve

Good progress, were you able to button up the motor yet?

[srsupertrap]

Need more parts?

http://cleveland.craigslist.org/mcy/4379860884.html

Although the 1981 GPz550 is the only dual shock model, I could use those forks, front master cylinder (mine is dry) & rear rotor . . . too far but please keep your eye our for an 1981

TIA

Need more parts?

http://cleveland.craigslist.org/mcy/4379860884.html

[srsupertrap]

Degreased the frame & rear wheel with 3 cans of degreaser. The rear wheel paint is still good but looks like I may have to paint the frame



Just a little bent

[srsupertrap]

Measured connecting rod end bearings journals tonight using the same Plastigage process



The service limit is .10mm just like the crank, #3 which is known to fail first measures .076mm






Lots of photos . . . All good



Consistent readings


These all look good too. Note at the front of each how the bearing insert is peened into place. Glad I don't have to replace them.



Service limit for connecting rod diameter is 32.96mm, I measure 32.98mm interference fit with the the Mitutoyo D/C


Add assembly lube to everything. I believe I have a good crank with no signs of distress at #3 rod

[srsupertrap]

Good sleuthing Steve. Must have been that trans gear then.

Bearings looking good.

Figured out the rings situation yet?

Yes, kudos to 7981GS for pointing me to a shop in France which has the Wiseco XC piston rings. JMJ speaks English quite well and I have already received 8 sets of 61mm rings. Although there is no ground shipping from France so this wasn't cheap either.

Old & in the way in the background . . . new upfront. Signing off

[tkent02]

Replaced the gear and missed a tooth. I wonder where it was hiding, or maybe they didn't even look. Congrats on finding it. Any more issues pop up?

You want to powdercoat those cases while you have it apart? I'm going to be home for quite a while.

[Nessism]

Good sleuthing Steve. Must have been that trans gear then.

Bearings looking good.

Figured out the rings situation yet?

[srsupertrap]

Poked around a little tonight to see if I could determine were the broken tooth came from.Have to look close because I inserted the tooth in the gears . . . Too small to be a crankshaft gear tooth



And the starter clutch (not wide enough)



But the best fit is here in #6. I can only guess but it looks like they replaced the gear set.

[srsupertrap]

Here is what I did Sunday, I inspected the crank bearings with Plastigage SPR-1. Did it very carefully, took my time, torqued to spec (18 Ft-Lbs) and confident I have good results. The service limit is .10mm



From left to right






All of the crank journal bearings consistently measure .076mm which is safely under the service limit. None of the bearings are flaking. Those readings are acceptable. I will probably use Brad Penn green oil to prolong its life when I button it up.


Next, what does the crank journal diameter measure? My crank has "no markings" & the standard measures 31.984 to 31.992mm. The service limit is 31.96mm. Since I am using a digital caliper I lock the adjusting wheel at 31.98mm and see if I have an interference fit. The 31.98mm fits over all the journal bearings. I drop the measurement on the digital caliper to 31.97mm and it's a tight interference fit on every crank bearing . . . which means its good.



I believe this photo accounts for the PO stating this engine was "blueprinted" . . . check out #3 pork chops



I will be checking the connecting rod end bearing with Plastigage after work this week. It does not appear a crankshaft failure parked this GPz550 some 27 years ago. Still a mystery