1982 GPZ 750 Easy restoration...psshhhhh, right!

The engine/alt cover I used powder coating on...one of those eastwood kits and a friend had a free oven so, why not! I cerakoted the carbs and a few other items. I kinda like the cerakote better, more expensive, but you dont get that weird occurrence when you try to shoot powder in tight areas where it repels itself if you know what I mean

So its time to start on getting her to run. She ran rough when I tried at first without the carb rebuild. I figured it need valve adjustment, like most do. I ran a compression test and she came up low, like 105 on three cylinder and nothing one one....uh ohhhh. So I pull the valve cover and give it a closer look. The first thing I notice is white paint on the cams...ugh, with the letters E on one and I on the other. Great, someone has been in here. Then upon closer inspection I notice how close the cam sprocket is to the housing...hmmm. Well if you know your Kawi, you'll see the issue right away. See it??? The speedo gear blank, which were left blank on the GPZ, is on the wrong side. Someone flopped the cams in the wrong way when they put this thing back together....arghhhhh. Its amazing it sorta ran, which was a dumb thing to try and start it without inspecting the engine more thoroughly at first. So I decide to do a poor mans leak down on the cylinder with no compression...sure enough, leaking out the intake when cylinder is at TDC...fuck, bent valve probably!!!! Well off with her head. This easy resto is now getting more expensive. The speedo says she only has 13,000 miles on her.....damn it!

Here's the leak down

As I wait for the valve do a little port and polish job and lap the other valves, since none of the others were bent. But I did notice the rough hone job on the cylinder walls...uh oh. Someone went deeper then just valves...fingers crossed as I dont want to have to bore this engine. As I waited for the valve I blast and redo the valve cover and bolts and the head bolts I cerakoted. It looks much better. With the new valve in place I bolt everything back up and attempt the fire her up.

Not sure if you realize, but the cam chain tensioner spring, under the cap on the tensioner, needs to be released before putting on the valve cover.  Otherwise, the chain will be over tensioned by the rub block in the cover, pressing down on the chain.

Thanks for that Nessism! I did try to follow the manuals directions but it was not real clear as to how to obtain the proper tension... But that makes absolute sense! Ive never done this before so its forums like this I glee some knowledge cause no one in my town really rides these old dogs!

Well got her to start up, but we have carb issues...of course. Revs on its own once it gets off the pilot circuit it seems...lean issue possible or vaccuum leak. I probably should have replaced the throttle shaft bushings...damn it. Also she seems sluggish. So I wanted to do a compression check, since I didnt recheck once I did the valve replacement. Sure enough, compression was low still, 105 pounds versus where it should be 150 so I squirted oil down the cylinders and BOOM, compression was up to 150...damn it again. Looks like Ill have to tear it apart again to see whats up in those cylinders!

Cylinders off and YEP, there was a reason someone got into the cylinders. Looks like water sat in cylinder 4 and caused some wear and they tried to hone it out...pshhhh. Well looks like an over bore situation. Looked into a Wiseco big bore kit, but my machine shop said there wouldn't be much cylinder left taking that much out. Plus I really didnt want to spend $700 on pistons. Plus the bore and hone charge...it would be more than I paid for the bike...ughhhhhhhh. I did find a smaller .050 overbore piston set on fleabay thats only $250...might go that route...easier to swallow that price. Any thoughts??? Wiseco vs. other brands?

Only a suggestion but given that boring isn't that expensive is it worth boring it 0.4 over and seeing what the condition is like (it will mean boring again to the correct clearance for the pistons) at least then you will know where you are before buying pistons and finding they won't do the job 

I'm using the cruzinimage piston kit from Japan, Its 69mm {810cc}  but stock compression unlike the wiesco kit, much cheaper though....
www.cruzinimage.net/2017/08/25/80-85-kaw...re-pistons-kit-69mm/
 

Nice work, Seriously!

What was your technique with masking / painting the tank emblems. Fine result!

H.

750 R1. Did you do the overbore yet? I was told by the machine shop that it would make the lower part of the bores to thin and would risk warping or heat damage and they would have to run it through the bore machine so many times that it would be like $400-$500 bucks also! He said If I wanted that installed id have to have it resleeved which is way more then I wanted to spend. Did you check into the machining yet?