I agree, those quote sound high. Especially the tire quote. Valve adjustment isn't too bad and jetting is just behind the tire quote. All can be done yourself if you are mechanically inclined. Doing the valves it is important to lock the valve lash gear in place to avoid having to reset it. Most important of all is be absolutely sure to mark the bearing caps for position and direction so that they go back on the way they came off. The actual adjustment is simple, measure the clearances you have now do the math to figure out how far out they are. Measure the shim you take out and add or subtract the amount you are out and get the proper shim for that valve. When measuring the old shim use a micrometer not a caliper since it probably won't be flat.

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