Britbike forum Forums British Motorcycle specific Brands Triumph bulletin board Calling John Healey or someone that can answer.

John, Thank you for all the info I have gleaned from your posts. I shipped my head today to Memphis motor werks to let Leo do his magic. So with that said, I wanted to ask you a few questions about putting later rocker parts in my 1970 rocker boxes. I have a line on a set of 1973 T140 complete rocker boxes. Can I transfer the internal parts into my 1970 boxes? I believe the 1973 and later have the spiral cut rocker shaft. So should I transfer the parts in the same order? I read one of your posts and you said something about adding two more factory washers. Any help is much appreciated. Thanks, Chris

Hi Chris,

Yes you can. Some things to note:

A number of these were assembled incorrectly using six (three per box) thrust washers with I.D. of 1/2" (70-1575) and two (one per box) thrust washer with I.D. of 3/8" (70-1330). This set up puts the spring washers against the rocker arms and prohibits oil flow out of the machined divots in the arms.

You need to swap the placement of the spring washer and thrust washer. You need to ditch the two 3/8" washers and replace with two more of the 1/2" washers. This will allow the "step" on the shaft to clear the washer when you swap the spring and thrust washers.

This was the incorrect assembly:



This is the correct assembly:



Note in the second illustration that part #54 (3/8") is labeled incorrectly and should read part #53 (1/2"). (Not to mention that the thrust washers are labeled backwards relative to the shaft orientation, but that's another can of worms!)

Finally, be sure you have later dome nuts too (UNF thread). I think the earlier spindles had CEI threads, but not sure when that change occured...I'm sure someone will chime in with that info.

HTH,

Steve

http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=344618#Post344618

Try this.

Thank you Gentlemen!

Pardon the interuption. Steve, the latter illustration with the spring washer on the outside, scrap the smaller washer to clear the step/shoulder on the shaft is the correct set up?

Ugh. I puzzled over those very two illustrations, finally deciding on the former since mine came apart that way.

I'll take them down again. I have a dowel for correct alignment. The worst part was getting the o-ring to go in without shearing. At the recommendation of a friend, I bought some uh, lube, at ...a...business that's not an auto parts store, and leave it at that.

It worked, btw.

Cheers

Richard

Correct assembly is the first arrangement shown. Thackeray washers go next to the rockers and washers go against the aluminum housing.

Scott. I think if you look at the history of this change that took place in 1969, the model that it was first introduced on and what did and didn't happen you will come to a different conclusion. The non-drilled rockers, with their "cut" ends, came out of design changes made to the Trident at Umberslade Hall.

Beside the new rocker arms the changes included a new rocker shaft with an oil groove to allow oil to migrate to the end of the rocker shafts, and a change in the positioning of the flat and Thackerey washers. While Meriden got the new rocker arms, the rest of the changes, including the oil groove in the shaft, and the change in the washers were not made. This dramatically decreased the flow of oil to the top-end. With the introduction of the 1973 750 twin models Meriden finally put a spiral cut in the shaft to allow more oil to flow. This was an improvement as far as it went. The ends of the Thackerey washers still found their way into the cuts on the side of the rocker and diverted the flow of oil away from the pushrod cup and valve tip.

Let me see if I have this right.

There are two different types of rockers, one is drilled and the other has a cut end, or what I would call a notch?

The Thackeray washers are correctly installed against the drilled rocker on the outboard end of the rocker and

for the cut or notched rockers the Thackerays are swapped with their respective washers and are installed against the rocker box housing?

I just sold a mutt of a Triumph for $2850 and I made $10,200.
$200 profit and a $10,000 education.

My education continues...

Correct.

My education continues daily!

Cheers,

Steve

For your '73: yes.

Cheers,

Steve

So the factory never installed the spring washers against the rocker housings after the change went into effect for the twins?

Did the Tridents have the spring washers installed against the rocker housings?

Scott, while they finally adopted the grooved shaft with the 1973 T140 Meriden never did put the flat washers against the rockers.

It wasn't until 1985, and the Harris Bonneville, did Brian Jones finally place the flat washer against the rocker arm.

Tridents always had the flat washers against the rockers.

Somehow the Hippy Dippy Weatherman must figure in to all of this...my next twin rocker box rebuild with notched rocker arms will have the change but I'm a little hesitant...uhhh...light increasing in the morning hours...beer was invented before motorcycles, make of that what you will

Mine have to come back down. I've got the placement of the first illustration. Timely topic.

Again, pardon the interruption. But thanks for allowing me to interject a query or two.

Cheers

Richard

No, you would have to understand the relationship between BSA, and their development group at Umberslade Hall, and the folks at Meriden. One company and divisions that tiu would have thought came from different planets.

Looking at the 1975 Trident parts manual shows the outboard spring washers up against the rockers... I guess things were pretty confusing at the old plant in those days. If I could lose my jed clampett accent, I would have fit right in.

Think it has been said before that parts manuals were not designed as restoration manuals ( very true in case of bsa) sometimes the images or info on the plates can be plain wrong, missing something or shown in what looks like the wrong place. How many times have you gone through a basket case, buying parts that you haven't realised is certain parts looming at the bottom of a box. It's only when the part arrives you go... Oh yer

The 1975 T160 Trident manuals and parts books are "Horses of a different color".

While it is true the T160 parts book clearly illustrates what you said, the workshop manual clearly show the washers next to the rocker arms. Remember, it was Norton that was responsible for the T160 and neither Meriden or BSA management had anything to do with it.

To organize all this in your mind you must be able to disconnect illustrations and applications from the intent of original design. The original design worked. It provided a lot more oil to the top end than earlier iterations.

So, the illustration in the A65 workshop manual is wrong?
It shows the spring washers next to the rockers, flat washers to the outside.
My '74 T150v parts book shows the plain washers next to rockers.

In 1971 it was not wrong. Later on they found a better way to do it.

Hi Scott,


Nope, 'fraid just the T160 parts manual is wrong.

The T160 head/rocker box drawing is an adaptation of the T150 drawing, used in all the T150 parts manuals from 1968 to 1974. Whoever did the original drawing hedged his bets, with various arrangements of plain and Thackeray washers at each rocker; however, certainly from 1970 to 1974, the order of bits is shown correctly at the ends of the exhaust spindle and the drive-side end of the inlet spindle, ... but, for some reason, the order at just the timing-side end of the inlet spindle was never changed.

When the T160 manual was prepared, because the rocker feed pipes had more bits, the decision was made to remove all the rocker feed bits from the head/rocker box picture and list. At the same time, someone took it upon himself to change the order of the bits at ends of the rocker spindles; unfortunately, rather than note that three were the same and only one was different, and check with the workshop manual, the only incorrect end was copied to the other three! Duh!

To echo Allan, parts books were intended for factory and dealer staff to identify parts, not as assembly instructions; that's what workshop manuals are for (even if they aren't always correct either ).

Hth.

Regards,

Hi John,


Ye-ea-ah ... like, as you've got grand-kids, you're "responsible" for your kids.

The T160 parts book doesn't have a publication date but it's recognizably in the Small Heath format, rather than the Meriden format, and I don't recall any problem getting one after I got my first T160 in 1977.

Otoh, the T160 Workshop manual wasn't available for years afterwards - I remember buying my (bound) copy out of the boot of Les Williams's car at a TR3OC AGM at the Coventry Museum of Transport, so that'd be about 1981. By then, was there any part of "Norton" that gave a monkey's about the T160? I suspect that, had it not been for John Nelson (who compiled it), we wouldn't have a T160 workshop manual now.

Hth.

Regards,

BSA is "another kettle of fish". What we are talking about refers to Triumph twins and triples from mid-1969.

Not to interrupt the "Who's your granddaddy" line of thought, but I think this contributes to those in possession of lesser lineage knowledge.

I've now swapped out, successfully I might add, which is saying something, the spring and flat washers that were in question inside the rocker boxes.

First observation is that with the flat washers against the arm and the spring washer against the housing, oil should be "encouraged" to travel from the inside of the arm and eventually onto the valve tip via a tiny opening on the shoulder of the arm now enclosed with a flat washer.

If swapped, spring washer inside, the oil would be allowed to go anywhere gravity so chose.

Second, with the spring washer now outside, getting it to go into place is something I liken to, oh, I don't know, trying to put a cat into a toilet - it will cling to any and everything in sight before considering going where you want it. The open ends of the spring washer act as claws to grab everything.

Just a word of warning. Your 7/16ths dowel for alignment of the various washers/rocker arms, a tiny screwdriver and the patience of Job are requirements for this particular task.

Also, ensure your last spring washer in line is in fact aligned. Mine got pinned between the arm and housing due to initial misalignment, halting the forward progress of the spindle and giving the washer what I call "fish head" (squeezed pretty flat, IOW).

And now back to our regularly scheduled programming, "Who's your granddaddy?"

Cheers, lads. Very timely as I was just closing this section up on on resto.

Richard