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started my bike up the other day and it was making a tapping noise coming from the front of the engine,as i reved the bike the noise goes faster let the bike tick over and it slows down,took it for a ride and its not running too good,i've just about had enough of this bike its one thing after another!! i'm prepared to spend probably about £200 to £300 to get it sorted if not then its goin on e-bay as spares :smt013 any ideas what the tapping noise could be cause i dont want to get ripped off by a garage and id like to know whats actually wrong.

Sounds like its either the cam chain or the valve clearances need doing. How many miles has it done and when was it last properly serviced?

The cam chain usually needs doing between 20K - 30K. The shims need doing depending hows its treated.

it was serviced in september.i dont ride it that much only at weekends and only flying about round the town where i live,just my luck that it fucks up as the decent weather is coming!!! any rough idea how much its gonna cost me....... oh yeah its done 42k miles

Were the shims done at the last service? If they were then its probably not them then, more likely the cam chain.

Cam chain job will probably be quite steep at a dealers cos the engine has to come out and i think you need to split the block from the cases which makes it a whole days work. You can do it yourself, quite a few people here have done recently, you can also manage it without taking the engine apart, all you ned to do is grind away at a bit of the casing so the cam chain will pass, some one here has also done that mod. You can also do it with the engine in the frame but i think its alot easier to time it up while its out of the chassis.

nah man the shims were not done on the last service,what the bloody hells the shims anyway

Shims sit between the top of the valve and the cam, they are basically a flat piece of metal, when they wear down you just buy new ones of the right size to make the adjustment.

Shims live between the rocker arm and the valve.
They are used to adjust the valve clearance.
Valve clearance is the gap between the rocker arm and the cam when the valve is fully closed and the cam is at it's lowest. It is measured using feeler guages when the engine is cold preferably after sitting overnight.

Valve clearance exists to allow for expansion when the engine get warm.

If you valve clearances are to small the valve will start to open too soon and stay open too long and the valve seats will suffer damage.............not good.

If you valve clearances are too great the valve will open late and close early and will not open fully...........no damage to seat but there will be loss of performance and if the clearance are very much too big potentially they will be noisy.

Correct valve clearances and good valve seats are essential for good performance.
Valves can be lapped in to recover seats that are not too badly damaged then measure and reshim. Valve seats can also be recut or replaced this is a specialist job.

Checking the clearances on a ZXR 400 is easy and changing the shims is also easy if a little fiddly you do NOT need to remove the camshafts to change shims. However if you need to lap the valves in the it's a head off job

Also and this is very much my personal preference use leaded fuel if you can or a lead replacement additive. Modern engines like the ZXR are designed to run on unleaded fuel but but using a leaded fuel or an additive will help protect your valve seats.

hey,thanks for that description of the shims.i recon i'll have a go at doin it myself sod the garage!! any idea where i can get some new shims?

I've got a good selection in my toolbox.

Failing that they are about £5 each from any good Kawasaki dealer

zxrtbone wrote:hey,thanks for that description of the shims.i recon i'll have a go at doin it myself sod the garage!! any idea where i can get some new shims?

Not quite as easy as that fella!

You need to not the clearances for each valve and compare them to the tolerances in the workshop manual. Note: The clearances are different for the inlet and exhaust cams.

For any valves that are out you need to remove the shim and measure that so you know what size you need i.e. + or – X mm

i think i'll let the garage do it,dont recon i'll be up for the job.taking the carbs off and giving them a clean is about my mechanical limit!!!! looks like i'm gonna be down a lot of cash then

Did you read the PM I've sent you

i've just read it,cheers for that mate.do you recon i would be able to do it myself? it would be the bullocks if i could as i cant be arsed to shell out to a garage,have you done the shims before?

If you can take the cover off and use a set of feeler guages then it should be very do able.

Yes I have done this job on zxr400, gsxr 600 and cbr600.
ZXR 400 is the easist. Hardest bit is getting the shim back in place but it's just fiddly...........a magnet is handy as well one like this



You'll need something to measure the shims with like a vernier like this




You have my number ring me and we'll chat OK

Pity you don't live nearby and I would come and do it for you.
I wonder how much a dealer would charge for doing this ?
With cheap flights maybe I could fly over do the job and still be cheaper than a dealer............joke

yeah man its a pity you dont live nearby!!! one of my friends came round yesterday and had a listen to my bike.he said that it sounded like the cam chain,do you think that i should replace the cam chain before doin the shims,seems like there's a few people on here at the moment talking about sortin the cam chain out.