Checking Valves & YZ exhaust timing for WR

First let me just say that before I got this bike my mechanic skills were limited to "Lefty-Loosey, Righty-Tighty."

I want to thank everyone involved with making the ThumperFAQ and assembling the fantastic instructions for uncorking and maintaining the WR. Your detailed instructions are clear and very easy to follow.

Before today I had done the throttle stop, airbox, exhaust baffle, and grey wire mods. The bike was great but running lean. Fixed that with the JD jetting kit.

Today I checked the valve clearances (all right in spec) and since I had it opened, I changed the exhaust timing to yz specs. All I can say is WOW. The bike still has the great low end torque, but it just keeps on pulling all the way to the top. Midrange and top end power greatly improved. I haven't had the chance to really test it yet but I can't wait.

Some observations for anyone planning to do this mod.

From beginning to end it took me 3 hours (I also cleaned and oiled my air filter) If I had to do it again it would be probably half that.

Follow the FAQ instructions to the letter. I had no problems opening the valve cover or finding TDC. I didn't have to remove the carb but had to disconnect the throttle cables and rotate the carb in order to access the cam chain tensioner. I bought a set of feeler gages at sears, but I had to trim them to fit the narrow slots in the cam caps. When removing the exhaust cam cap, definitely pay attention and stuff a rag (as per instructions). That little clip that fits into the grooves in the cap and the cam is easy to lose into the cylinder. I zip-tied the timing chain to the intake cam so it wouldn't shift. Then just lifted the exhaust cam and rotated one tooth clock-wise(12 pins between marks) Only pain was getting the cam cap back on with the clip in the grooves. I had to fuss with it for 10 minutes or so. Closed everything up, the bike fired on the first kick.

Thanks again

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