Pitted Cams

Well, I lifted the lid on the ZRX this week, All shims are within spec, Still cannot find the cause of the persistent ticking noise it makes. It sounds like valve clearance, but it isn't. Noise comes from the top of the engine.Bill.

I had the quietest 1100 in town until a couple of weeks ago. I did the shims and most were tight but in the lower end of the range, some were too tight and one had no clearance. I loosened up a lot of the clearances with shims of one and two stages smaller, "all but one still in spec and in the upper range, one too loose now" After that it was as noisy as shit? Apparently this is common. I went back down and found a couple I could tighten up and did those. Quieter but still a little rattly till it warms right up. Problem is the standard shim size increments reach from one end of the range to the other ~0.05, so you have no choice about which end you land in. Some in the know reckon the bike runs better with them all at the lower end of the clearances? All I know is my bike purred like a kitten and now it rattles a fair bit. It does start easier though, seems to rev smoother too so I'll live with the noise.

...... Noise comes from the top of the engine....

You might need to inspect all the cam guides and camchain as well, sometimes these are responsible for top-end 'ticking'.......

Mine sound like a truck, I like it that way.

It will be the reeds fluttering in the air injection boxes - they are located on the rocker cover. They tick like crazy some days, other days you can hardly notice them.

The cam pitting thing is well documented - cause is pure speculation, but it seems that the condition develops and then causes few problems other than giving the owners a bad gastric condition.

The best advice I have seen so far for this "problem" is - use good oil, change it often and ride it until it stops.

Woohoo! Kawasaki is coming to the party.

Even though my bike is out of warranty (since about 3 years) they will fix my pitted cams for free!

They will get them reground, NOT replaced with similar Kawi cams.
They will also fix any rockers that need it. A number of the rockers are badly scuffed due to the pitting.

I noticed on the pitted cam lobes, that the pitting occurs at the "back-end" of the lobe, ie after it has contacted the rocker. They also develop a bit of a ridge at that area, which may explain the ticking noise, as the rocker passes that ridge.


Now to get them to do the ZZR cams. Pitting only, no major ticking yet.



By the way, my "reeds" aren't used - Ivan's block-off plates.

Bill.

Its a disgrace that KHI have not done something about this before now. Like someone said, it goes back to the GPZ900R and all sucessive incarnations of that engine.
My Dad is a Ulyssian on his third GTR and all have had the same problem. Its certainly not a result of thrashing the bikes thats for sure! Thankfully Kawasaki have fixed the old boys GTR under warranty.
I wondered if maybe in 1984 or something they made a MASSIVE batch of poor quality camshafts blanks that they are still working through?? But how could they have seen back then that that engine would evolve into a shaft driven tourer, a fire breathing 150hp sports tourer, and a naked powerplant??
Basically its just shithouse Quality Control.

That said, with 60,000ks on it, my nine hauls ass and shows no signs of pitting. And the paint is lovely too.

BTW, my mate built a GSXR750 SRAD bike with yoshi pistons, carillo rods etc, and guess what killed his brand new freshly rebuilt engine?? The chrome that chipped of his new Ivan Tighe cams!

More info.

Kawasaki are rebuilding/regrinding my cams.

They also offered to look at the rocker arms in the head of the ZRX, and said they would get any that require it, repaired.

Well, the condition of some of the rockers was so bad (chrome came off, bad scoring, etc) that they did not do this.
Instead they gave me 16 new kawi rocker arms. Retail per rocker arm: ~$60. I call this good service.

Cost to me? Labour only, and since I dismatled it myself, and will be re-building it myself, there is no money involved. All I need to do is buy a head gasket, which retails locally for around $140. However, ordered from the US, it is a lot cheaper.

Bill.

Another victory!

I took my '02 ZZR1200 in for its regular service (24000 km) at my local Kawi shop. Soon after I got home, they phoned me to say that one of my cam lobes was badly pitted and in need of repair. "Here we go again" I thought (just had the same with the ZRX).

Next moment the mechanic asked when when I wanted it done, at no cost to me! It involves removing the engine from the frame, removing the cams, regrinding/machining them, etc. Also, they will spring (again, like my ZRX) for 16 new rocker arms. All labour, etc at Kawi's cost.

What I need to do now is work out a suitable time. Bike is not under warranty, and I am the 2nd owner.

The Kawi shop: Mack1, Midland, WA. Highly recommended!



Bill.

now that's aftersales service bill! Out of warrenty and everything, go figure?

Opened up the Rex (2001 model original owner) @ 48000 k's to fit ZZR cams & found #4 inlet lobes pitted badly. Bike is ridden daily, Dragraced monthly & is meticuously serviced. I still have the cams, wonder if Kwaka will look after me ?

ZRX is all buttoned up again, and I just did a 5 day trip from Perth to Emerald (Central Qld) - 5000km, without problems.

I intend to get the bike back to Perth after the MotoGP (going there!) in Sept, and I will then check out the fixed cams.

So far. so good.


ZZR is in the shop at the moment.


Bill.