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Discussion Starter · #1 ·
Hi all,
Thanks in advance for the help of all your knowledge!

71 650 OIF
Got the rocker boxes off currently and felt some binding/notchy type feeling in rocker movement when rotating on shaft by hand. May well be that it’s the point they go to from pushrod/valve extension and I’m rotating them past that.

i don’t think it’s shaft but rather maybe spring washer biting/binding a lil but on rocker arm face.
I don’t think it’s likely an issue givin how much pressure exerted by valve spring/pushrod, but thought it would be nice to get some nice smooth movement rather than feel the clickynness in the rotation.
Spring washers have obvious wear marked on em from rubbing metal on metal.

Got em stripped currently soaking in kero.
Can post picsif needed when I get home

thought I’d ask others findings or thoughts on the subject?? Cheers
 

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Hi broganh, The Thackery springs can catch in the notch at end of rocker sometimes.

There is a way to restack washers so spring is not against the rocker, but flat washer is. A few ways to do it. As an side benefit it's said it improves oiling. If new shafts are needed, get the '73 & newer shafts 71-3945. They have oil feed scroll machined in the shaft which improves lubrication.

Also, is the shaft worn out of round or has varnish on shaft/rocker as you said was binding on the varnish?

I'll see if I can find photos of how I like to restack washers tomorrow.
Don
 

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Discussion Starter · #3 ·
Champion and scholar! Great info on the replacement, thankyou.

Yes, I thought they were catching in rocker arm divot where they face acting washer - but appeared not so at least on one, was giving feedback feel (although most likely not an issue once under engine pushrod/valve spring pressure), as was binding up in a more touch senestice fashion before leaf end of spring washer reached said divot.

seems it could be an abnormal spot - but givin Total arc of rocket movement would be set and limited by pushrod lift height - it may just be that top out point that is setting a lump/ridge in Rocker face against washer face.

will take some pics and share. Maybe a good reference for those in future - even if not much in the way of change-out or servicing is required.
 

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I just had a look myself just to confirm how I have always assembled these rocker spindles. The parts manuals show the thackeray washers next to the rockers, except the T140 manual. However, the T140 repair manual clearly shows the same as the earlier arrangement, though the manual does imply two 3/8" washers - not so. Although the rockers have the same part numbers from the year dot until some time during 1979, when they changed to using UNF adjusters, there were some detail differences. From 1968 the oil feed to the pushrod pins was cut off, with the later pins ('69 ish) having pins with no hole, and the rocker itself undrilled, thus stronger. Whatever you do, DON'T put the thackeray washer next to the alloy, it will chew it up. After fitting the spindle, remembering that a 3/8" ID washer goes to the threaded end, and you can push the ends of the thackeray washers around until they locate in the rocker groove. Oh, and be careful that the end of the spindle enters the last thackeray washer correctly, sometimes a bit of a fiddle. What I have found is that not all thackeray (or thrust) washers are created equal, a stretched thackeray washer will try to dig into the thrust washer, and the thrust washer should be the correct thin hardened steel, and smooth so the end of the thackeray washer can slide easily. If you think about it, the thackeray washer should rotate with the rocker, just sliding on the thrust washer. Incidentally, I always fit stainless steel end caps to the spindles (yes, they do come off), I got my friends from Motalia to get some made. I also always use mushroom head adjusters, they are lighter (because of the internal allen adjustment) and give the valve tips and guides a much easier time.
Don will no doubt have a look too, he's a lot more thorough than me.
Cheers,
Mick.
 

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Illustrations for rocker arm assembly:



Text Line art Design Font Parallel
Text Line art Diagram



Regarding placement of Thackary washers against alloy, John Healy had this to say:

"This placement of the flat and Thackeray washer came about when they were updating the triple during the early design phase. The Thackeray, or spring, washer against the aluminum rocker box continued from the first to the last of the BSA and Triumph triples. It has never been a problem nor have they worn into the side of the rocker box!!"

My favorite description of installing the Thackary washers comes from T140V-Rich. He describes it as "putting a cat in a toilet".

That description comes from a thread which pretty well runs down the history and the misconceptions about the assembly order. For those interested:

Thackary washer placement thread
 

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Hello Stuart,
I'd have to say that the only problems I've ever seen in the valve train worth worrying about, other than the horrible standard adjuster setup, and given half decent oil, is wear on the exhaust followers. I always use late nitrided cams and try to use the setups that maximise oil flow to the followers, but as they are in an oil fling "shadow", it's all a bit iffy. I'd like to try making a "well" or trough for the cam to run in, but truth to tell, none of the engines a see nowadays do much in the way of milage, so I've never got around to it!
Cheers,
Mick.
 

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If that's a proper Triumph thackery washer - unlikely - then it has been stretched. True triumph thackery washers have the washer ends flat as per Hermits illustrated post.
 

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Discussion Starter · #13 ·
Thought they must be wrong according to posts above but doesnt look too dissimilar to product available to replace them ?? wondering if its worth ordering new ones.
Anyone bother linishing the shaft removing wear marks etc?


729403
 
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