To set your valves first remove the rocker cover and spark plugs, then jack up one rear wheel. Put the car in high gear. Now turn the rear wheel forward by hand. Watch the rockers move. You can see them from the rear of the car.
One method uses the TR engine firing order and the "rule of nines". The number of the rocker that's down plus the number of the rocker that is adjusted always totals nine. When 1 is down, adjust 8, when 2 is down adjust 7, when 3 is down adjust 6, and so on.
Another simple way of adjusting valves is to adjust the
ones opposite those that are open. You will notice that the
engine always stops with two rockers down. It will be the first
and third or second and fifth from the front, or the first and third or
second and fifth from the rear. Simply adjust the opposites.
i.e.. When one and three are open, adjust six and eight.
Works every time!
Use "go, no-go" feeler gage approach to setting valves. The Triumph Engine valves are set (inlet .010 to .013 and exhaust .012 to .013 cold). A .010/.012 feller gauge must be able to be inserted between valve stem and rocker arm but a .013 must not be able to be slipped into this gap.
A good tool will help insure that you do a good job! They are quicker and usually result in more accurate settings. These are feelers with the end ground, usually. 002. The .010 gage will be .010 on the end and .012 farther up. Once you set the valve using the ground portion of the blade, you then slide the gage on in and make sure that the .012 section does not fit.
If you use the rubber rocker gasket and have glued the gasket to the rocker cover then you can pop off the cover, jack the wheel, adjust the valves, button everything up, and be back on the road in fifteen minutes.
A loose valve is noisy, wears quicker, and robs power. A tight valve will self-burn and self destruct. Set your valves right and often.
Ever wondered why clearances must be set when the engine is COLD? Engines don't run cold. However when engines are hot i.e. at running temperature the valves clearances are the same as when they were set cold. BUT during the warm up the push rods take longer to become fully heated and thus the engine becomes taller faster than the push rods become longer. In other words the valve clearances decrease until the engine temperature stabilizes throughout. Did you ever notice that the old VW engines were relatively quiet when cold but got noisy as they warmed up? Aluminum engines vs. steel push rods! TR engines always tick a bit. It tells you they are happy.