I have an 03 CRF 450 that I bought used. It has been hard to start since I got it when cold. I know the previous owner never did anything valve related to it. So, I checked my valves and they were all in spec except for the right side intake valve (brake side), which from what I understand is rare. I couldn't get the smallest feeler gauge to slide through, which was a .0015. I'm not sure if it was because it was to big still or just to flimsy. Either way, the valve is close to zeroed out. I took out the cam and now I need to replace the stock shim. My question is, do I just replace the shim with one that is .004 to .006 smaller? Thanks for the help and/or advice.