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Hi Gar,
remove the entire unit and make sure the advance is working properly
Before removing points and auto-advance unit, if you mark the points plate and AAU in relation to a fixed mark on the timing cover inside the points compartment, the marks will help with reassembly.

Remove the 1/4" bolt in the centre of the points plate.

There is a Triumph workshop tool - D782 (60-0782) - for 'breaking' (not literally ;)) the auto-advance unit's male taper loose from the camshaft's corresponding female taper but ime a reasonably-long 5/16" bolt will do.

As yours is a '65, I expect the AAU extraction thread is 5/16"-26 Cycle; however, don't exclude the possibility it's BSF (22 tpi) or a later replacement UNF-thread (24 tpi) unit ... :rolleyes:

You should be able to screw in the bolt 'til it bottoms on the end of the camshaft. When so, knock the protruding bolt with the heel of your hand once in each direction (up and down or side-to-side). This might 'break' the AAU-camshaft taper but, if it doesn't, ensure the bolt is hand-tight against the end of the camshaft and repeat. The AAU should 'break' free with only a few good hand thumps on the extraction bolt.

The Triumph workshop manual has Section B28 "REMOVING AND REPLACING THE CONTACT BREAKER" (.pdf pages 78/79, paper pages B26/B27); it's light on removal instructions, better on reassembly as it covers both 4CA and later 6CA points plates.

Hth.

Regards,
 

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Super Moderator
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Hi Kevin,
didnt know that there were three thread possibilities.
what were the circumstances around the BSF 22 threads?
Never come across a BSF-thread AAU. However, I wouldn't claim vast experience of 1960's Britbike AAU, just thought I'd mention the BSF possibility in case it happened neither a 5/16"-26 (Cycle) nor a 5/16"-24 (UNF) bolt fitted the AAU on Gar's bike?

Hth.

Regards,
 

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Hi Gar,
65 Trophy
primary cover does not have an inspection cover
Correct; Triumph didn't add the separate small round cover over the alternator rotor (which had the moving timing mark) and fixed timing pointer 'til '68.

hoping to just static time.
Unwise imho. Triumph added the strobe timing marks to reduce the number of holed pistons causing warranty claims. Nearly sixty years on, the fuel we're supplied is nothing like the fuel Triumph used to tune their engines, you aren't going to change things like the combustion chamber shape so ime you want to do as much as you can to make your bike's engine reliable on the fuel you can buy, including setting the spark timing as reliably as possible?

recommend purchasing the real tdc tool.
Degree wheel & the mounting bolt kit.
With degree wheel you can lock AAU to full advance & static time or strobe time with unlocked AAU.
If you own one of these bikes, you basically need most of the tools the dealership used. As they say, cost of ownership.
+1.

I would like to preserve the originality of the bike and see if I could live with the points setup.
I have the 4ca setup with points and the condensers are in there too.
Bear in mind Lucas developed the 6CA because the 4CA spark timing was too inaccurate - frequently, if one cylinder's spark was accurate, the other one wasn't, :( owners or mechanics ended up "splitting the difference" between the two cylinders (so neither was completely accurate ... :cool:).

Also bear in mind the 4CA's condensers failed prematurely due to engine heat - some parts books show a second pair of condensers outside the engine (mounted in holes drilled in the front tank mounting strip).

Finally, going back to the spark timing accuracy, the mechanical AAU simply cannot compete with the persistent accuracy and far longer advance curve of electronic ignition ... however, EI are 12V, your bike's electrics are 6V ... :cool:

Your points cam looks like you have ET (energy transfer) ignition on some photos & normal on others.
:confused:

View attachment 789277 View attachment 789278
For clarity, these are (likely patterns of) '70-on Lucas "17M" coils, 17M6 because they're '6V'.

TR6SR wasn't fitted with ET; of the 650's, only pre-'68 TR6(S)C's and some T120C's/TT's were fitted with ET. The ET AAU is different - less advance - not completely impossible a DPO could've fitted one to your bike, but both types are marked with the advance degrees.

Hth.

Regards,
 
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