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Changing Shims and Adjusting Valve Clearances
Unhook the rubber housing for the bank of relays on the right hand side. this will let you see the end of the cam shafts clearly.
You need to be able to see the positioning marks stamped into them.
Using the crankshaft again, turn the cranks to the T1 mark so that cylinder 1 is exactly at top dead centre.
You will see a little arrow stamped on each crankshaft.
When Cylinder 1 is at TDC the arrows will be horizantal and exactly pointing at each other. You can just about make them out in this picture.

Ensure both the T1 mark and the arrows are all aligned.

From this point on the engine must not be turned at all.
When you are happy everything is aligned perfectly use a socket with a long extension to undo the top nut on the cam chain tensioner. This located just under the throttle cable cam assembly,
Take care as you undo it to withdraw the spring and the washer carefully.

Take care of the washer especially. If you read the service manual, this washer should be replaced, but Triumph have thoughtfully decided that they will not sell this 99p washer on its own and you have to buy the complete tensioner for £50 or so.
Undo the two retaining bolts on the tensioner
Withdraw the cam chain tensioner unit
Four parts on the tensioner.
Clean them up. Make sure the ratchet in the main body works freely and extends. Lift the ratchet and compress it.

And look after the copper washer.
Now undo and remove the top pad assembly from the top of the cam chain.

Its a good idea before you do this to fill the top of the cam chain tunnel with a lint free rag or workshop paper roll.
Anything you drop down there is going to drop into the crank cases which potentially means a crank case split to get it back out again.
This is bad. Dont do it.
Remove the two outrigger caps from the right side of the cam shafts.

The head, cover and journal holders are all matched with a single bore. Damage any of them and you have to replace the lot!!
Next take off the cam ladder. This cast and its under tension from the valve springs, so it is essential that the bolts are undone a little at a time in the correct order.
That way the tension is released and the cast ladder doesnt get cracked.
I numbered the bolts with a black marker pen just to make life easier. You can just about see the numbers in the photo.

(I will add a diagram of the bolt order at some point)
As you take the outrigger caps off one at a time, mark them with a permenant marker so that you can be 100% sure they go backon the same way around. Place them somewhere safe
Once tension is released, remove the bolts and lift off the cam ladder
Cam ladder and O ring seals Throw the O rings away. You will replace these.
Unhook the cam chain and lift out inlet camshaft
Unhook the cam chain and lift out exhaust camshaft.
Dont worry about the cam chain. It cant drop into the cam chain tunnel and can safely be left resting on the pin as shown
Cam buckets are now exposed.
Camshafts on the worktop.

You can identify the inlet camshaft from the outlet camshaft by the fact that the inlet camshaft has a groove around the centre section, the outlet camshaft has a smooth mid section.

Dont mix them up.
Use a magnet to lift out the cam buckets.
Im using a magnet I stole from my little boys toy box.

I must get myself a proper magnetic pickup tool :-)
Turn the bucket over.

See the shim
Tiny aint they.
All that work to get at these little tiny things
All 12 buckets removed
Its very importand that every bucket goes back to the same valve it was removed from. So each bucket needs to be stored with its corresponding shim for each valve.

Egg boxes or sealed bags are brilliant for this
Measure each shim with a micrometre or a digital caliper. Dont go by the size stamped on it. The stamped size is usually right, but not always. Trust the guage not the label.

Go through each shim for each valve and check it.
Swap it out for the correct size needed to bring the gap into target range.

I have a spreadsheet I need to add that makes working out the shims a breeze.
Mix a small pot of 50% Moly grease and 50% clean fresh engine oil
Put a dab of it on each valve sping cap
Place each shim into the corresponding valve cap
And place each follower bucket over the corresponding valve cap and shim
Replace the camshafts.
Cover every can journal and facing surface with the moly grease/oil mix, This is important as it keeps the journal faces lubricated when you start the engine the first time before the oils has circulated.

Hook up the cam chain positioning the cam shafts so the timing arrows are horizontal and line up with each other.
Cam shafts in place, cam chain hooked up and all the cams and journals coated in the moly grease oil mix
Coat the new plug well O rings in fresh engine oil and put them in place.
Keeping the front run of the cam chain taut, torque up the cam ladder.
Remember to torque the bolts a bit at a time in the correct order to prevent fracturing the ladder.

Then replace the outrigger caps making sure they go on exactly the same way round and torque them up.
The camshafts will turn slightly as you torque up the ladder.

Use a spanner to gently take up slack, make sure the front run and then the top run of the cam chain is taut.
Do not move the crank shaft. Just take up slack.

Check the arrows on the camshafts line up with no slack in the cam chain.
Replace top pad assembly
Ta Daaa!
Almost done
Re assemble the tensioner with the tension are compressed and the new gasket covered with a thin coat of clean engine oil.
Fit spring, copper washer and top nut. As you fit this you should hear the ratchet extend and take up the chain slack.
Double check the arrows on the camshafts a final time.

If they look like this, you have fucked up. Take the tensioner off and adjust them again.
If they dont line up, use the slack in the back run of the cam chain to unhook it from the teeth on the camshaft and slip a tooth in the direction required, take up the slack in the front run and top run again and check the timing arrows again.

Repeat until you are sure the arrows line up perfectly.
Make sure the T1 timing mark on the crankshaft has not moved.
New cam cover seals in place.
Place the new cam cover seal onto the cam cover. Use a few dabs of grease around the edges to hold it in place.
Put a small bead if gasket sealer around the U shaped recesses on the head.
And then, what I think is the hardest part of the entire job, fit the cam cover back in place keeping the rubber gasket in place and making sure it is seated correctly all the way around.

Unless you are lucky and you have 4 arms, it will take several attempts to get it seated corectly before you can torque it down.
Remove the paper bungs from the plug wells
Fit new spark plugs
Refit the SAI hoses and the dust shield
Refit the relay rack
Reconnect all hoses
Fit and connect coils.

Shims changed - Camshafts refitted - Job done.
Things I didnt do in this service and still need to add.

Use plastiguage to check clearance on journals.
Add spreadsheet for valve shims and credits for spreadsheet author.