1981 Kawasaki GPz550: Restoration

[srsupertrap]

Weekend Update photos: DIY rings compressors made this a one man job



Used the hose clamps for #1-4, top ring popped out but since it was constrained a quick push with a tap on top took care of it.



Never measured the deck height but its close



Crazy home made carb adapters, holes look like they were drilled by hand. Will have to remedy someday



I filed the cylinder fins to match its GPz heritage




Cam Timing marks are in perfect alignment w/o the tensioner installed. Next check valve lash & degree cams & fix another helicoil

[srsupertrap]

Yesterday I used the hose clamp method but added a stainless steel sleeve from the Depot's plumbing section. I drilled out some rivets then used the dremmel to get the S/S band width slightly larger than all the rings. Used 5 heavy duty cut off wheels to cut two S/S bands. I found the idea here probably should have used the plumbers tape http://drriders.com/topic6882.html Once the clamps were positioned correctly just tapped the cylinder right on



Last week Chris (cdnoel) brought over his ring grinder to open up the piston ring gap #4 from .008 to .011.. Piston ring gap is now (1-4) .011, .011, .013, .011. We were surprised by how much movement the wheel had back n forth



Don't recall ever seeing an oil ring like this . . . I guess it prevents the ends from overlapping

I used hose clamps that came from Wurth Products. Their screw mechanism is a lot closer to the band than most hose clamps. I bought those hose clamps many many years ago when I put my KZ750/4 together.

Just hope who ever bored your cylinder put a nice chamfer back on the bottom of your sleeves. If not I don't think you will get the pistons and rings into your cylinder.

Try using popsicle sticks to push the rings into the cylinder. If you slip, they won't scratch the piston.

[srsupertrap]

Get yourself four nice hose clamps and compress the rings with them. Set the tightness of the hose clamps so that they slide down when you place the cylinder down on them. You want just enough tension to get the rings into the bore. You can do 2 and 3 first then do 1 and 4.

I would NOT use RTV near any Kawasaki gasket. Something like the brush on K&W Coppercoat, or Gasgacinch would be the only thing I would ever use on the base gasket. Make sure you use NEW o-rings around the oil nozzle in the base gasket too!!!

Take your time and don't get frustrated if you have to start over a few times trying to get the rings into the bore.

Trying to visualize how the hose clamp method works in my mind eye. Every hose clamp I have lying around has the same design were that screw mechanism on the outside of the clamp is actually wider (or higher) than the hose clamp band which would compress the rings. I would visualize when you lower the cylinder liner down over the piston, the liner will contact the screw mechanism first because its higher up than hose clamp band . . . When you pull the hose clamp down just a smidge I think you would lose the compression on the top compression rings which is just 1mm thick.

I am just trying to understand because tonight I failed quickly when trying to install the cylinder using the finger tip method with the help of a friend from work. We were able to get the top compression ring to go on #2-3 but the ring gap was almost closed. We resorted to small screwdrivers but he lacked a deft touch so I thanked him for his help and decided to try again later.

Feel free to clarify . . . I stopped by the local auto parts store & their Chinese hose clamps were the same design too

[Nessism]

Every Suzuki and Kawasaki motor I took apart had that grey colored case sealant on it, so thats why I still use it. Never tried the 1207B myself.

Well, I spent at least two hours cleaning my KZ750 cases on Saturday and there was black silicone between the halves. Pretty sure it was 1207B.

Threebond 1104 which is now 1184 is the case sealant that is the same as the gray Yamabond. 1104/1184 is semi drying synthetic rubber, not silicone. That is the only case sealant I have used since back in 1971. I never had a case half weep, or leak with that stuff. Even where someone used big screwdrivers to pry the cases apart. I never used it on any gaskets except like you said on the KZ650/4 and KZ750/4 clutch gasket where the case halfs meet. Every Suzuki and Kawasaki motor I took apart had that grey colored case sealant on it, so thats why I still use it. Never tried the 1207B myself.

The Threebond 1211 the white silicone is great around o-rings in base and head gasket oil o*rings that always leak on Kawasaki fours. I use a thin coat of it on my GS1000 and KZ1000 cam plugs. Only had one cam plug leak using that since back as far as I can remember.

[Nessism]

Threebond 1207B, which is one of the most common case sealers, is silicone. I don't think there is anything inherently wrong with the stuff, you just need to follow the directions and use it sparingly.

The service manual for the KZ750 calls for sealer on certain locations of certain gaskets. You might want to check your manual Steve and see what's specified. I looked though the 550 manual but couldn't find similar reference to that from the 750 manual. The guys at KZrider.com get all gooshy in favor of copper coat on the head gasket. I know the 750's are prone to leaking from the head so I'm leaning toward the copper coat myself.

[blowerbike]

i have only used 2 small screw drivers.
depends on how much chamfer is on your liners.

Get yourself four nice hose clamps and compress the rings with them. Set the tightness of the hose clamps so that they slide down when you place the cylinder down on them. You want just enough tension to get the rings into the bore. You can do 2 and 3 first then do 1 and 4.

I would NOT use RTV near any Kawasaki gasket. Something like the brush on K&W Coppercoat, or Gasgacinch would be the only thing I would ever use on the base gasket. Make sure you use NEW o-rings around the oil nozzle in the base gasket too!!!

Take your time and don't get frustrated if you have to start over a few times trying to get the rings into the bore.

[srsupertrap]

After checking rings gaps, opening up one set of rings to match Wiesco ring end gap, I am now ready to install the cylinder block but lacking the extra set of hands to compress the rings. Any innovative method to install the cylinder by one self?

Q: Do you think the base gasket requires RTV, if so blue or black

[Rob S.]

My first encounter with a GPz 550 came in the summer of 1981 on route 17 between Monticello and Binghamton, NY. I was on my '73 Z1 with a 4-into-1 pipe, on my way to Rochester, with a small knapsack on the rear of the seat.

Beautiful scenery, cruising at 80 to 85 mph when something red catches up to me - a GPz. He was intent on overtaking me, but I rode with him for a ways at about 110 mph, until the curves and the rain grooves got the better of me. But not him - he was a lot more sure-footed than me on the curves.

I had read about the suspension of the GPz550, so I didn't take it personal, and continued on my way at a 'leisurely' 80 mph.

[Nessism]

Assuming you don't have a bunch of cylinder wear, it doesn't matter much how deep you go into the cylinder before measuring. 1/2" - 1" is plenty.

[srsupertrap]

I am moving onto checking piston ring end gap (Wiseco XC 61mm 615cc) & want to verify the process. Using Wiseco formula & numbers below

Q: What is the proper ring end gap for my GPz550?
A. This chart will help illustrate the minimum ring end gaps:

Top Ring	2nd Ring	Oil Rail
0.004"	0.005"	0.015"

Multiply your bore size in inches times the value on the table above (to convert metric bore to inches, divide your metric bore x 25.4. For example, 61mm divided by 25.4 = 2.4015?, multiply this times the value on the chart)

Top Ring: 2.4015 x .004" = .0096"
2'nd Ring 2.4015 x .005" = .0120"
Oil rail: 2.4015 x .015" = .0360"

How do you measure & what depth should these measurements be taken. I have no bore gages at home just feeler gages

[srsupertrap]

Thanks for all the positive feedback . . . Big T, Rob.S, cowboyup3371 & posplayr.

Rob to answer your question I won't be changing the color scheme & probably won't paint till next year at this rate. It will like the first photo but with a black exhaust & bit shinier

Steve

[posplayr]

Build looks really good.