I previously requested set-up procedure for ignition timing a 5TA fitted with a Lucas 18D2 Distributor but apart from one member, no other contributors replied. Perhaps most members have side points fitted or the 5TA is a bit of a rarity. However, for the benefit of those who do own a 5TA or indeed a 3TA and are not in possession of the facts, I have found the info myself and would like to reiterate this info straight from a users manual I managed to find. Here is the procedure as per Instruction Manual No 4 :-
1. Turn the crankshaft so that the right hand piston is at top of stroke. (neither of the the right hand tappets on the inlet or exhaust are raised) 2. One method of determining the crankshaft position is to use a circular degree disc on the engine driveshaft. in conjunction with a rigid pointer on a suitable mounting. 3. Set the disc or pointer to read 0 degrees with the right piston at the top of its stroke with both valves closed (both tappets down).This is TDC and is the correct timing position for the 3TA & 5TA models only. 4. Remove cover from distributor 5. Turn the distributor shaft until the points are open. 6. Adjust the gap to between 0.014" to 0.016" by slackening the screw securing the fixed contact plate. Insert a screwdriver between the two studs on the base plate and the notch in the fixed contact plate, and adjust the position of the plate until the correct gap is obtained. 7. Tighten the securing screw and recheck the gap. 8. Holding the distributor so that looking from above, the hole from the clamping plate is at 9 o'clock and the low tension terminal is at half-past seven. 9. Keeping the distributor in the same position, turn the shaft so that the brass contact on the rotor arm is at 12 o'clock. 10. Insert distributor into the crankcase so that the gear meshes with the camshaft and insert and tighten the clamp plate anchor bolt. 11. The distributor is now ready for more precise timing.
This was the information I was looking for and hope that it might benefit others who were as puzzled as I was, and might have only sorted the timing out on side timing cover versions from 1962 onwards.
Jim, Sorry I didn't catch your earlier post or I would have helped out. On my 1960 T100A, I used the procedure that you have posted to get my bike set up, and it will work to at least get it started. Your 5TA should not be any different.
Once running, you will need to rotate the distributor, while holding it down I might add, to get the bike to run as smooth as it can, then tighten the distributor clamp. I have never found a way to strobe a distributor bike unless you have the later side cover and marks on your rotor.
I converted mine from an ET ignition to a single coil ignition and have not touched the points, coil or distributor in 2 years of running. Fun bikes to ride!
Many thanks for your added information and encouragement etc. I have just rebuilt this engine from a pile of bits but renewed the essentials etc. It's a long time since I owned a 5TA and remember ordering a new machine on the 1958 London Motorcycle Show, but my mechanical memory has degraded somewhat.
It's a spare engine which I intend to sell so that I can have go at rebuilding another engine. This is engine number 3.
My existing Triumph T90 has 1969 500cc T100S engine and is ready for firing up from a complete rebuild.