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Hello! I spotted some scratches on the top of a cam. They are not very deep but can be felt with the finger. The clearance on that valve is alright. Could this cause problems? Should I replace the camshaft? I have no idea from where those scratches appeared...

how does the rocker arm look?

i wouldnt be using it in my engine if thats of any consolation?

if you have a cam re-grinding place near you they can probably reprofile that cam, it will mean using a thicker shim on that valve, most places sell up to 3.5mm, so if you are currently on a 2.80 shim you can have 0.3mm taken off the base circle, that should be enough to clean up the cam lobe for you.

if the cam is dead, you can put in a new cam, but make sure to check the oil clearance with plastigauge to be on the safe side.

As always banner001, thank you for your support! Unfortunately I cannot find any shop in my area to re-grind the cam so the only alternative is to buy another one.

After all, I decided to squeeze my wallet and buy another camshaft. Does someone have one for sell? I prefer to buy here.

you also need to check the rocker arm for wear, if you cant see it visually at the moment you will need to remove the cam covers, the camshaft and inspect them that way...i would suspect that its dug out a bit of the hard coating from the race of the rocker...

After a closer inspection I found out that those marks are not scratches but small dimples.
I found out about this problem when I made the valve clearance adjustment. The gap on that valve was only 0.1 mm (tolerances are 0.12 - 0.17 mm).

I will also check the rocker arm soon to see if I need to replace it also.

In the meantime I have to found a replacement for the camshaft.

There are 2 engines for spares on uk ebay...i think ones a H1 and one L4...I will check for you....im not sure if they would split the head or sell a single camshaft even(but you can only ask huh)..if one is not available easily it can be reground.

if you can feel them with your fingernail, they are probably too deep.

but its your engine, your call, remove the camshaft and inspect the rockers properly and get back to us with the results.

Yep, I will do this at the end of the week.

Well, I inspected the rocker arm and has no unusual wear so I guess the camshaft have those scratches from the previous owner. I decided to run a wile with the current camshaft but when I find a replacement I will replace it. Now I have another problem and I'm really stuck. See here:

viewtopic.php?f=117&t=16813&start=15

Don't worry about it, that is a pitted cam, Not at all unusual on Kawasaki cams of this era. As long as the pitting doesn't cover the whole width of the cam it will not affect the valve clearance and there is a school of thought that says that the pit actually acts as an oil well, so not a problem. I discovered a pit on one lobe of my cams 6000 miles ago, took detailed photos of it, and 6000 miles later it hasn't changed at all, and neither has the valve clearance. I've owned the bike from new so I know its full service history. It's just a Kawasaki thing, no biggy.

Thank you Tirpitz! Good to know from another owner who experienced the same problem that this is not a big deal as I thought.

your initial picture made it look like 3 long deep grooves/cuts to the top of the cam, any wear there translates to wear on the rocker arm, thats why i was concerned, small dimples are of no real concern, just remember to check it everytime you do your valve clearances.

Yep, I will check it every time.