maciekmaciek19 wrote:Thanks guys.
Just measured the gaps. All exhaust valves seem to clear ok. 6 inlet are out of limit but the gaps are below the spec - they are too slim - 0.8 -0.10 mm. Does that sound right? I thought the gaps would be getting bigger not smaller...

I've just started doing mine and I'm getting the same thing, can anyone shed some light on this?

what about cylinders 2 and 4 am I missing something here !

NC wrote:what about cylinders 2 and 4 am I missing something here !

Nope, you're not missing a thing. 2+4 are the same as 1+3. Gap sizes are the same for inlet and outlet. I was going to do a bit of a write-up for 2+4 but there's no need.

oliherst wrote:

maciekmaciek19 wrote:Thanks guys.
Just measured the gaps. All exhaust valves seem to clear ok. 6 inlet are out of limit but the gaps are below the spec - they are too slim - 0.8 -0.10 mm. Does that sound right? I thought the gaps would be getting bigger not smaller...

I've just started doing mine and I'm getting the same thing, can anyone shed some light on this?

Basically what happens is that the valve stems get stretched and the valve seats wear. The stems can stretch due to the high revving demands of a motorcycle engine. Valve seat wear is the norm in all engines, all this results in the valves closing up, hence your tight clearances. What it means if you don't get on top of this is that the valves will not fully open to allow the fuel mixture in and exhaust gasses to exit. Bad news for your engine

Thanks V, makes sense. Is doing the valve clearances enough? Or is that just a repair rather than prevention?

Doing the clearances is just part of routine maintenance which will prevent more costly operations having to be performed on the engine.

in case any of the In Line 4 people are reading this guide i have a shim template. i have set it up for my bike the ZX6, but you can modify the specs to your bikes clearances. PM me if you want it.

Sorry to sound daft, but what do you if the tolerances aren't right?

You replace the shims required to bring it into the tolerance using the methods displayed by Viper.

It is daunting at first but once you have done it the satisfaction is very great.

CMSMJ1 wrote:You replace the shims required to bring it into the tolerance using the methods displayed by Viper.

It is daunting at first but once you have done it the satisfaction is very great.

lol, not when you have done it 4 times to two different bikes because the first time one happened to measure between the rocker arm and cam instead of the rocker arm and shim.

nope!! wasnt me i swear it!!