Well from your prior posts it still sounds like you have some carb issues , as for the valves , what you want to do is with the bike on a stand so its level , remove the large round plug on the clutch side , then remove the small one on the ignition side , and have the valve cover off , and pull the spark plug , now , crank the engine over by hand till you see the cam lobes point towards the rear around 2 o'clock position , as it is getting there go real slow with the kickstarter (by hand) and watch the cam gear marks , as soon as they are flush , stop , now look at the ignition cover hole/mark and look at the clutch side marks (it should be a arrow/triangle and a dot) , ALL 3 marks need to be aligned , to be at TDC , then and only then do you check the valve lash , sometimes regular car/automotive feeler gauges are to wide to work right in checking the lash , they make feeler gauges specifically for these bikes , they are really narrow .... with that said , check your lash and see what you get , there is no "use this shim" scenario , every bike is different , that is why they make shim kits .... there is some hope if you have a 185 and larger , as that means there is still some life left in the valves , for how long , is different for every bike , some may stay in spec 1 ride , others 40 rides , but once they start moving it is only a matter of time before they are toast
Now in one of your other posts you mentioned a head bolt (should be nut) missing , there are only 4 of them , so with one missing , there is a strong chance you also have a blown head gasket ....... once you get the valves in spec , I would do a compression check , you should be around 57 psi (it is supposed to be low due to the decompressor , otherwise it would be like trying to kick over a Harley)
, if it is less than that , then you could have valves not seating and/or a blown/leaking head gasket , since in your other post you mentioned a oil leak , it is a possibility the head gasket is also part of your hard starting issues , not to mention the carb issues , not to mention the valves being closed or close to it .........
To check the shim size there is a calculator here that might help you figure it out , but the quicker way I think is to just grab a smaller shim from the kit , go a couple sizes down (2) ,remove the timing chain tensioner , pull the tower bolts and tilt the assembly down so the chain has slack , put a wire or something (bungee cords work well) around the chain and pull the tower/cam out , tie the chain to the bars so it does not get slack in it and come off the crank gear , pull the buckets , and swap the shims , and put the tower back on and tighten it by hand (it is very low torque so don't hoof down on it , or you will strip it out) , , you do not need to put the chain back on at this time , then align the 2 slash marks flush with the head and make sure the lobes are facing the rear , then check the lash , if you can get a gauge in , check it , and see where you are at , if its at 4 or something , then pull the tower , and buckets and go 1 more size and see where you are at , get as close to 0.005 or 0.006 that you can , but no lower than 0.004 .. once done , if you do not have them , I can give you the torque specs to put everything back together ....
Here is a link to the shim calculator https://www.crfsonly.com/calculators/cr ... m-calc.php
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