TravisZack wrote:Ok... so front cylinder
In - 0.13mm – Shim size - Barely visible but looked like 207? I don't think that's a size they come in but I've no way of accurately measuring.
Ex. - 0.23mm – Shim size - 1.2 - this will need a 1.12, right?
No point taking a chance on the markings being correct, so buy a cheap digital vernier and measure them.
They're cheap, honest, about the price of two
shims.
Tenner in the UK.
But broadly you're right if your sizes are correct.
By Jove, i think he's got it!
Almost always the shim range is 172 to 187 or so as standard.
If the shim is much smaller than this then it may be that the valve seat has been cut into the head after a seat re-cut. i don't think this is very likely, and hence my suggestion that you measure it accurately.
Occasionally, if I haven't got a shim of the right thickness I'll thin one out to the next under size by using grinding paste on a sheet of glass.
Takes bloody hours and wears your fingertips away, but save waiting until the right size is in stock a few days later at the main dealer.
But when that happens I end up with a shim that says one thing and measures another.
You can't trust the etching markings, is all I'm saying.
It's not falling off, it's an upgrade opportunity.