GPZ500S............ New bike needs attention

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GPZ500S............ New bike needs attention

I have a new bike, Gpx500s 1994, 15.500 miles...........

I've been reading up that they had a problem with the flywheels and the magnets on standard one can fly off and smash up the stator plate. How can i find out by looking at the flywheel if its the original or a pattern one........?

Got the haynes book of lyes in the post, awiting arrival...

Sounds quite clunky at tick over with what i would say is like a big end gone, but i know its not that at 15.500 miles.... I've balanced the carbs and it does sound a bit better, also the cam chain you can hear that racing around the crank and cam gears... Is this normal...

Also gotta check the cam chain adjuster as i've heard they can fail if it has the standard one in.......

But on thing i have noticed is that it looks like there are blanking plates on the pair system valves on top of the rocker cover....... So i would think thats one thing been sorted out on it.......

Also was thinking of lifting the needles up with a small washer just to richen the mixture up, found this really worked on a cb250 and cb400 i've owned..... What ya think..... Do they need it or not......

Lots to answer in here guys, any info would be much apprieciated....

Many Thanks in advance......... Get ya tech heads on, i need some real help on getting to know these bikes...........

First off - stop assuming that your bike has all the problems that they supposedly suffer from, it'll cloud your judgement. Those GPZ500 engines have been around a long time and are tough as old boots. All standard parts "can fail" but the GPZ engines are mostly reliable. A big end could easily go at less than 15k miles if the engine has been abused and starved of oil, but if it's only at tick-over then it's extremely unlikely to be a big end. You say it sounds clunky at tick-over so you've balanced the carbs. With 15k miles in 22 years it's likely that the carbs are quite gummed up. If you can't be bothered to remove, strip and clean them then adjusting the pilot screws a bit might help. Or they might be blanked off as it sounds like it's a US bike.. Does the clunky sound reduce when you pull the clutch in? Not sure what you mean about the cam chain "racing" around the crank and cam gears. If you can hear it howling then it's probably over tight or so loose that it's rubbing on the casings. I'd suggest popping the cam covers off to have a look at it and checking the cam chain tensioner is working. Again - with such low mileage the tensioner might have seized slightly. Leave the needles alone at the moment - get confidence that the engine is fine and happy, then give it a clean air filter etc and see how it goes. There's no point "tuning" something that's not running perfectly in the first place. It just costs money and leads to more questions and uncertainty.

Hi tappy. .. carbs have been cleaned, but I'm likely to take them off and give them a good going threw... not blanked off popped a tiny screwdriver up in situ and dropped into the groove of the screw, just one won't move....needs a good soak.....
The engine sounds the same, clutch in clutch out I did check that. ...
No cam chain is not howling. ...
I'm gonna do the tappets clearance once I get the Haynes book of lies. ...not sure if there shims or screw locknut.... not sure if you know that tappy....? Whilst in there I'll check the tensioner......
I'm using flushing oil in with the oil to work it's magic..... I like that stuff, my option it works some magic....
Oils as black as ars*holes,was changed last January so been in a year.....
I also use zx1 friction reducer.... can't do no harm and 5100 motul and new oil filter. .. and air filter.......
And plugs......
So hopefully give it a new lease of life......
Thanks for your input tappy. Much appreciated. ...remember you from when I had my slingshot......

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