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Hi Steve, I saw very clean aluminum on trans wall behind high gear. That’s why I wondered if rubbing.

Regarding bores, looks like the honing pattern is not near 45deg like hone was ran too fast or was zig zagged too slowly. I would rehire, see what you get. I expect you’ll end up .040 over though.

The very fine metal whiskers on your magnet are normal. Rub them with fingers. Most will be powdered metal. From where I don’t know. I saw same whiskers on Porsche 911 drain plugs 100% of time & on my bike also. The big chips… that’s not normal. My big chips were from right main bearing race flaking apart. It chewed up scaveng ball seat in oil pump.

If oil is drained cold, strainer or in frame filter will have a thick sludge ring around it. That’s normal. Hot it’s very little. Later years had tin ring around lower in frame screen. Paper filter the inside of filter is totally clean where sludge ring is. Seen that many times.

I’ve changed oil & cleaned both motor sump & frame screens every time, 1500 miles. Still seethe sludge. I change primary oil every time too.

Depending on how you cyl holes were drilled turning studs over won’t matter. Stud threads will now bottom in threads on bottom. I’ve seen this on 2 cylinders now including my own. Some use 1/4” ball bearings under stud ends. They felt “spongy” to me. I made slugs out of 5/16 steel rod each cut & faced square to specific length. One hole was 1/8” deeper! These felt sold. The 5/16 studs long end down didn’t need slugs or balls.

When using larger washers on studs you may need to trim rocker box gaskets to clear. Also make sure rocker box casting clears. My boxes fouled washers. I ground OD of washers smaller to just clear. Still fair amount larger than original washers. Not so easy to trim covseal rocker gasket.

Oil in center studs is from rocker box leaking down stud from top, but more likely head gasket seeping up studs & can seep out under nuts & the oval plate.

Oil on the 3/8 studs is very common. Can run down head nuts etc. I’ve seen this numerous times on good motors with no real external leaks. Just as with center studs seeping head gasket will send “oil” there also.

Combustion can condense into what looks like motor oil.

I’ve only used copper head gaskets.

If rebored file head gasket to even with bore so copper isn’t hanging into combustion chamber.

When torquing head gasket or any gasket the gasket flattens & thins. The gasket material displaces sideways. This is with copper or paper. You need a little wiggle room at bolt/stud holes to allow for this. If not gasket bunches up & makes a high spot. This promotes seeping & divots on head surface.

The cylinder can be low in middle. Very hard to skim & recut the grooves. Using 120 grit paper on surface plate the cylinder can be flattened nicely. I do until Starrett straight edge pinches .0005” feeler blade tightly no matter where I put I’d. Don’t figure 8 it. Straight side to side & front to back motion on paper.

Head can bend. Often it will have dips. Especially between center bolts, & center of theY at front. Careful measurement will show not bent but targeted low spots. These will seep. I find head is harder to flatten than cylinder. Same thing no figure 8. Very easy to remove metal around outside & not get flat.

At a point skimming is only cure. Very hard to get less than .005-.007” removed. That’s real life. A steel ruler is not a straight edge. You can but .0005 & .001” feeler blades on eBay or tool supply houses. Get a few, they are fragile.

Regarding valve stem tips I’ve refinished several to good results. If guides are good enough don’t change them. Triumph valves have narrow margins on heads when new. Grinding 45 you’ll often be way too thin. The valve & seat wear spherical. Just lap them by hand with suction cup & fine compound until all pits gone. Mount head so stem is vertical during lapping or it will lap crooked.

The valve adjuster screws can be refinished with emery paper in lathe or electric drill held in vise, if not too bad. Pay close attention to radius.

I’ve been comparing mushroom adjusters to normal ones. Interesting…. The radius is same. Exactly same line contact patch. If valve geometry is very off it can keep adjuster from running off stem tip. People say they last longer. Onl 2 possible reasons. Better metal. Or… the large end collects & holds more oil… my bet is it holds more oil. Or longer life is perception not fact. I’ll tell you in 5 years. Don’t think the head rolls on stem. It slides just like the normal one. It’s actually slightly lighter though.

If you need guides you’ll have to cut seats. Grind or replace valves. You’ll ending up replacing them. Leave seats wide to factory spec. Do not narrow seats as for racing. Lap & solvent check valves for leaks after grinding.

All the flattening & fitting pays dividends. Runs better & zero leaks.
Don


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Hi, I don’t believe the ID of inner race changes between C2, CN, C3 bearings. It has not on my limited experience on drive side or timing side roller.


Even within the same brand you should never exchange parts of a roller bearing with an other. This engine's drive side roller bearing should have a C2 condition bearing. This is even more important if the inside race is a slip fit on the drive side mainshaft. You must be sure the rotor nut is PROPERLY tightened and secured properly with a lock tab. Some blue loctite on the rotor nut is recommended.

Quote
When using larger washers on studs you may need to trim rocker box gaskets to clear. Also make sure rocker box casting clears. My boxes fouled washers. I ground OD of washers smaller to just clear. Still fair amount larger than original washers. Not so easy to trim covseal rocker gasket.


You should first address the recess in the head surface created by the original washers. Then replace them with the same (82-2184) washers used on the outside 4 head bolts. The CovSeal, and most 71-2599, gaskets are already cut to clear the larger 82-2184 Triumph washers. It is common to have to remove a little bit of the rocker box casting to clear the new washer. It is typically such a small amount that it can easily be done with a machinist three corner scraper (look it up)!! If you do your home work you will find that Brian Jones, Triumph's chief design engineer, made this change on the LF Harris bikes in the mid-1980's. Nothing new here!!

Quote
Head can bend. Often it will have dips. Especially between center bolts, & center of theY at front. Careful measurement will show not bent but targeted low spots. These will seep. I find head is harder to flatten than cylinder. Same thing no figure 8. Very easy to remove metal around outside & not get flat.

At a point skimming is only cure. Very hard to get less than .005-.007” removed. That’s real life. A steel ruler is not a straight edge. You can but .0005 & .001” feeler blades on eBay or tool supply houses. Get a few, they are fragile.


In to insure your engine is usuable with today's fuel you should NEVER remove any material from the cylinder head's gasket surface. It is the only way to insure your effort to toughen Triumph against destructive detonation, and pre-ignition, is to have the head straightened. This is routine work in any shop working on engines using overhead camshafts. Triumph heads bend back, just as easily as the pushrod tubes bent them. Rarely do you need any heat.
You are paying attention to the work required to "toughen you engines combustion chamber to detonation?"

Quote
The clips that I removed are the ones in the first photo. If I replace, should I use the same type or can I use the type seen in the second photo.

The radius of the clip MUST match the radius of the groove in the piston!!!! You would be safe using the same brand/type/size as original and check that it fits snugly in the piston and show no sign of being able to move. Never put a circlip made from sheet steel in a groove cut for on made from wire, or visa-versa.

Quote
Regarding reusing rod bolts- I've had a failure that I don't think I'd have had if I used new bolts. I believe one of the bolts had been over torqued at some point before I got the motor.

Triumph changed the rod bolt torque when they changed to UNF threads. They went from 27 to 22 foot pounds. They did this because the new nuts were made from a better grade of steel. The later nuts were made from better material, and heat treated, making them less able to stretch when tightened. Tightening one of these later nuts to 27 pounds is not if the rod bolt will break, but when. With the older, softer nut, the nut would distort before it would over stretch the rod bolt. If you are not sure, the best way is to check the tightening is using the bolt stretch method mentioned by Steve.

[quote] Depending on how you cyl holes were drilled turning studs over won’t matter. Stud threads will now bottom in threads on bottom. I’ve seen this on 2 cylinders now including my own. Some use 1/4” ball bearings under stud ends. They felt “spongy” to me. I made slugs out of 5/16 steel rod each cut & faced square to specific length. One hole was 1/8” deeper! These felt sold. The 5/16 studs long end down didn’t need slugs or balls. [quote]

All of the stock Triumph T140 cyclinders I have serviced over the years the cylinder head bolts in question were drilled to accept the "tit" on the four inside 3/8" bolts. It can be assumed that the fitters found that they could put the head gasket on quicker if the tits were up. BUT if you do some history on Umberslade Hall's engineering team they specified the BSA head bolts of the same period with "tits" on their head bolts and the way it was done it was obvious the tits went into the cylinder. Also when you go tits-up people tend to thread the stud into the cylinder to the point where the bolt runs out of threads. This can cause the top of the cylinder bore to distort adjacent to the bolt hole. This is the last place where you want the piston ring to lift off of the bore. You want the stud's longer threads going down. When installed properly you should see a half dozen threads above the gasket surface. You can trace this practice back to P.E. Irving.

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anybody wanting NEW C2 DS roller bearings should see my garage sale add-- thanks, bob fletcher


59 Bonne (in high school!)--67 TR6c (building)--68 Bonne(building)--69 Bonne (sold!)- 70 TR6r (sold!)-79 TR7v custom (building) - CRF 250x & XR 400 dual sport w/ SM wheels (super fun!) & just bought two Honda CT-90 trail bikes in rough shape!
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Mr Healy;
do you say better bolts, less torque; however ARP bolts are even better and they want 32 pounds of torque.
Why not those balls under all the 3/8 studs not only the inside ones?

Thanks

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Originally Posted by reverb
M
Why not those balls under all the 3/8 studs not only the inside ones?
Thanks

Because the two inner 5/16" studs do not pose a threat to cylinder wall distortion.

Steve


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...3/8 is what I mentioned not the 2 5/16...

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reverb -

There are four(4) inner 3/8" studs. Which 3/8" studs are you referring to?

I have the ball bearings in the 3/8" stud holes on the '77 Jubilee since 2012. Works well.

Steve


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...are not 8 3/8 and 2 5/16?

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Quote
do you say better bolts, less torque; however ARP bolts are even better and they want 32 pounds of torque.


ARP rod bolts have their own specifications! NO, the reference from Tom Gunn's correspondence while he worked at Umberslade Hall, explains the change in torque specifications was about the improved rod bolt NUTS.

Quote
Why not those balls under all the 3/8 studs not only the inside ones?

I have never had to use balls under any of the 4 studs (the out side four 3/8" hardware are bolts, not studs). There hasn't been a need. That's someone elses idea.

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however ARP bolts are even better

I have found the hard way that " Better CAN BE good's worst enemy". Better requires engineering skills, testing and understanding the results.

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Hi; thanks; my doubt was regarding that this engine HAVE 8 studs no bolts

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Originally Posted by John Healy
All of the stock Triumph T140 cyclinders I have serviced over the years the cylinder head bolts in question were drilled to accept the "tit" on the four inside 3/8" bolts. It can be assumed that the fitters found that they could put the head gasket on quicker if the tits were up. BUT if you do some history on Umberslade Hall's engineering team they specified the BSA head bolts of the same period with "tits" on their head bolts and the way it was done it was obvious the tits went into the cylinder. Also when you go tits-up people tend to thread the stud into the cylinder to the point where the bolt runs out of threads. This can cause the top of the cylinder bore to distort adjacent to the bolt hole. This is the last place where you want the piston ring to lift off of the bore. You want the stud's longer threads going down. When installed properly you should see a half dozen threads above the gasket surface. You can trace this practice back to P.E. Irving.

At the risk of being shouted down again, threatened with private messages etc. whistle the 'tit' is no more than a Unified thread identifier introduced when BSC etc. stud threads were changed to Unified...

[Linked Image from i.postimg.cc]


...and why it's there at the upper end of the dogged 5/16" barrel stud. The longer dogged end certainly goes down so the short relieved end obviously cannot...
[Linked Image from feked.com]

...The Unified identifier is also on other studs that were changed to Unified such as the UNF-UNC barrel base studs that CANNOT be inverted.

[Linked Image from thebonnevilleshop.com]


http://www.tioc.org/partsbookstriumph/pb-tri-650-1968%20-no6%2099-0880.pdf

[Linked Image from i.postimg.cc]

Same Unified identification was used on Norton Commando studs.

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Originally Posted by John Healy
I have never had to use balls under any of the 4 studs (the out side four 3/8" hardware are bolts, not studs). There hasn't been a need. That's someone elses idea.

Reverb - I did it based on advice given to me here by Pete R (R.I.P.)

Superfluous, perhaps, but I had the 1/4” balls lying around so I did it.

Steve

Last edited by JubeePrince; 12/21/21 10:08 pm.

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L.A.B On the T140 the tit end has the longer thread. It is the longer thread that this is all about. The turned down section is as long as it is to clear the end of the threads in the cylinder and bottom out. Have you checked out the last iteration of the BSA A65 head studs. P.E. Irving used this variation on many of his engine designs including the Vincent. He did this years before it was adopted to indentify Unified threads. Hillybilly measured a cylinder with the short end down and found that the stud distorted the bore by a .001” or so adjacent to the stud.

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Originally Posted by John Healy
L.A.B On the T140 the tit end has the longer thread. It is the longer thread that this is all about.


Yes, I agree that it is the longer thread that it's about.

Originally Posted by John Healy
The turned down section is as long as it is to clear the end of the threads in the cylinder and bottom out.

If, in the case of the 3/8" stud, the turned-down section was long enough to bottom out then there'd be no need whatsoever for the suggested ball bearing to be placed beneath the stud and without it then I believe the stud simply screws down to the bottom of the thread.


Originally Posted by John Healy
Have you checked out the last iteration of the BSA A65 head studs.

Yes, and only seems to prove my point that the unthreaded section needs to be significantly longer for the stud to bottom out in the drilling!

[Linked Image from i.ebayimg.com]



Originally Posted by John Healy
P.E. Irving used this variation on many of his engine designs including the Vincent.He did this years before it was adopted to indentify Unified threads.

Hillybilly measured a cylinder with the short end down and found that the stud distorted the bore by a .001” or so adjacent to the stud.

I'm not disagreeing or disputing that although Vincent barrels were alloy so perhaps distortion around the stud holes at the joint face was more of a problem?

What I'm saying is the relieved end of the 3/8" Triumph studs (that the 5/16" studs also have) isn't anything to do with it in my opinion as the point I am making is that the Unified identifier would appear to be too short to be of any practical use hence the addition of the suggested ball bearing to fill the gap but I take it you accept that in the case of the Triumph studs the short relieved section is to identify a stud as being Unified thread?



I believe the actual reason for the significantly longer plain section at the lower end of the 5/16" stud is so the stud bottoms before the stud thread reaches the unthreaded section at the bottom of the drilling that could result in distortion of the cylinder walls due to the 5/16" stud holes being extremely close to the cylinders if the stud thread was forced into the unthreaded section and is not there to prevent the upper end of the stud thread 'bottoming' against the barrel face.

I don't believe the 3/8" studs were installed "the wrong way up" by some "dumb factory workers" trying to save a few seconds on the production line.

Whether the engineers got it wrong is a different matter but I honestly don't believe the 'tit' was anything to do with it.

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anything to do with it

Please make clear with what you mean by "it".

I think that you are trying to say that the tit has nothing to do with the long thread. But in this case the tit has always been cut on the end with the longer thread. This make the tit relevant, and an easy marker to reference. They even appear this way with aftermarket studs. If you put the tit end down, the long thread is down and there is no need for 1/4" ball bearings.

Quote
This is the last place where you want the piston ring to lift off of the bore. You want the stud's longer threads going down. When installed properly you should see a half dozen threads above the gasket surface.

I think I made it clear when I posted this that you want the long thread down. The difference between the distance between the root of the 5/16" thread and the 3/8" stud and the cylinder wall is a bit over .050". On a .060" over bore it closer to .020".

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Originally Posted by John Healy
Quote
anything to do with it

Please make clear with what you mean by "it".

I think that you are trying to say that the tit has nothing to do with the long thread.

Exactly.



Originally Posted by John Healy
But in this case the tit has always been cut on the end with the longer thread. This make the tit relevant, and an easy marker to reference.

Yes and I'm not disputing that only that the tit itself as far as bottoming in the stud hole is perhaps irrelevant.


Originally Posted by John Healy
They even appear this way with aftermarket studs. If you put the tit end down, the long thread is down and there is no need for 1/4" ball bearings.

That is what I would disagree with as the short tit in my opinion isn't long enough to 'bottom' the stud.


Originally Posted by John Healy
I think I made it clear when I posted this that you want the long thread down. The difference between the distance between the root of the 5/16" thread and the 3/8" stud and the cylinder wall is a bit over .050". On a .060" over bore it closer to .020".

Once again I'm not disputing that although personally, I don't invert the 3/8"studs.

So, what's your opinion of the Gilardoni alloy barrel studs (presumably made by Harris to the original factory spec.?) as they have the Unified 'tit' but cannot be inverted as they are UNF at one end (with the tit) and UNC at the other?

[Linked Image from i.ebayimg.com]

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Harris originally had UNF to UNF, prone to stripping , not sure of the exact timing, but Mrs Bloor’s little lad stopped Harris using the Gilardoni’s, the UNC may post-date that, when the barrels were made available to the after-market. John at JH Motorcycles would know, as he used to sell them - and it is he selling the studs etc now.

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Originally Posted by TinkererToo
Harris originally had UNF to UNF, prone to stripping , not sure of the exact timing, but Mrs Bloor’s little lad stopped Harris using the Gilardoni’s, the UNC may post-date that, when the barrels were made available to the after-market. John at JH Motorcycles would know, as he used to sell them - and it is he selling the studs etc now.

Yes, according to the Harris Gilardoni alloy barrel kit fitting instructions, the barrel studs had coarse thread at one end as it states that the "Long dog point [?] coarse thread end of the stud goes into cylinder.", however, although all studs have a coarse thread, it appears only the 5/16" studs had the dog point.

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Quote
 "Long dog point [?]

Dog-eared /or dog-point [Linked Image from rhfasteners.com]

Dog-eared pickets [Linked Image from ashbylumber.com]

it could be real dog ears [Linked Image from toegrips.com]
or also when the corners of a book page are folded down intentionally as a bookmark ,
or when a book with a lot of wear from use or poor handling ... has had the Corners knocked about
[Linked Image from sarahhollowell.files.wordpress.com]

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...Mr Healy; I always read; but seems now that my eyes were not good enough, that you mentioned the tits down with the ball and NOW you say
"... If you put the tit end down, the long thread is down and there is no need for 1/4" ball bearings."
Even I saw photos with the studs, the balls and what not...

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If the depth of the drilling (making an allowance for the angle of the drill point) and the length of the stud that screws into it are the same then it shouldn't need a spacer (ball bearing).

I think it's unlikely for the thread to be cut to the very bottom of the drilling in any stud hole, presumably why the 5/16" stud has the 0.165" length of dog point to enable it to bottom out, therefore, in my opinion, the 3/8" stud might need the same or greater length of dog point.

[Linked Image from i.postimg.cc]

[Linked Image from i.postimg.cc]

Therefore, the question of whether a spacer is required or not could easily be answered by measuring the depth of the drilling (first ensuring there's no ball bearing) and the length of stud that will screw into it.

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Much of the discussion to ball, or not to ball, tit or no tit, certainly can beg the question. The problem I wished to address in my own work, and share with others, is to prevent cylinder barrel distortion at the top edge of the bore adjacent to the 3/8" studs. Others had measured this distortion, and in the some cases, the distortion is visible by a small worn area adjacent to some, or all, of the 3/8" studs.

Installing the studs with the long thread down addresses this. Ball, tit or what ever. Even if the studs are over tightened, there is no chance of distorting the top edge of the cylinder bore where the stud runs out of threads as it is intentionally, or inadvertently driven into the cylinder.

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JH:
“Installing the studs with the long thread down addresses this. Ball, tit or what ever. Even if the studs are over tightened, there is no chance of distorting the top edge of the cylinder bore where the stud runs out of threads as it is intentionally, or inadvertently driven into the cylinder.”

This makes perfect sense to me. In essence, avoid the situation where an unthreaded part of the stud may be forced into the top of the barrel stud hole, with the consequences described.
So at least some threads should show above the barrel surface.

I do also wonder about what goes on at the bottom of the stud hole.
If a stud without a long tit is screwed to the bottom of the hole (assuming its thread is long enough to allow that), then as it reaches the tapered threads at the bottom of the hole it will also exert a spreading action on the material around it.
Perhaps this effect will be less than that at the top of the barrel, but even so I would think it undesirable.

I suspect the tit is intended to prevent the bottoming of threads at the bottom of the hole, then the stud thread length ensures there is no problem with bottoming at the top of the barrel.

I can’t see any purpose to studs with long tit upwards at all (it is far longer than necessary for a lead in), though I fully appreciate LAB’s explanation of the small UN identifying reliefs (not tits).

I suspect the ball business derives from folk achieving the above conditions without inverting the studs, which probably works as long as there’s enough length left inside the headnut (with the tit inside it) for the rockerbox bolt.

I think JH’s explanation is the correct one.

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Originally Posted by John Healy
Much of the discussion to ball, or not to ball, tit or no tit, certainly can beg the question.

You seemed confident before that the 'tit' was significant. Now I'm sensing doubt?

Previously you said...

Originally Posted by John Healy
All of the stock Triumph T140 cyclinders I have serviced over the years the cylinder head bolts in question were drilled to accept the "tit" on the four inside 3/8" bolts.

...I believe the stud pilot drillings would normally be deeper than the cut thread and not intentionally "drilled to accept the tit" as I am doubtful the short 'tit' is long enough to reach the bottom going by the previous drawing, also indicated by the examples of the BSA studs thoughtfully brought to my attention with long dog points, same as the two 5/16" studs that also have the Unified identifier at the upper end.

I do not, however, accept it can be "assumed" , that "...the fitters found they could put the head gasket on quicker if the tits were up.." as you said previously and I'm doubtful it would be any quicker.


Originally Posted by koan58
I do also wonder about what goes on at the bottom of the stud hole.
If a stud without a long tit is screwed to the bottom of the hole (assuming its thread is long enough to allow that), then as it reaches the tapered threads at the bottom of the hole it will also exert a spreading action on the material around it.

I suspect the tit is intended to prevent the bottoming of threads at the bottom of the hole, then the stud thread length ensures there is no problem with bottoming at the top of the barrel.

It is my understanding that is why the 5/16" studs have the long dog point at the lower end (but still has the 'tit' at the upper end) so the stud thread is prevented from being forced into of the unthreaded section at the base of the drilling thereby preventing the cylinder from bulging due to the 5/16" stud holes being extremely close to the cylinder walls, more so after a reboring.


Originally Posted by koan58
I can’t see any purpose to studs with long tit upwards at all (it is far longer than necessary for a lead in), though I fully appreciate LAB’s explanation of the small UN identifying reliefs (not tits).

Only the 5/16" studs have the "long" dog point and I don't think there has been any uncertainty about which way up the 5/16" studs fit.

Originally Posted by koan58
I suspect the ball business derives from folk achieving the above conditions without inverting the studs, which probably works as long as there’s enough length left inside the headnut (with the tit inside it) for the rockerbox bolt.

The long threaded end must screw further into the barrel before it bottoms at the end of the thread resulting in less stud length above the barrel face that may or may not be significant but the ball bearings perhaps reduces the depth the studs screw into the barrels


Originally Posted by John Healy
I think JH’s explanation is the correct one.

Again, I have no argument with the fitting of the longer thread down only that the short 'tit' that up to now appeared to have been significant.

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