new shims??

[WB450r]

im getting a new shim kit here soon so i needa know how do you know what shims to to use..this will be for the 2 shims under the rocker arm..i heard theres a way to tell by how they feel in position/how much slack they have..any info would be appreciated..thanks

[blacknblue#2]

You must have a set feeler gauges to measure the clearance between the rocker arm and the shim. Its nice to also have a set of calipers or 0-1 mics so you can measure what size shims come out and that will give you an idea of what size shims need to go back in. Also if you adjust the exhaust valves thats gonna throw the clearance off on your decompressor pushrod so it will more than likely need to be re-adjusted also which can also be measured with the feeler gauges