[Freakmaster]

Notice the fulcrum point is a greater distance from shaft centre, (better) by virtue of a larger shaft OD. It's probably not difficult to use a roller bearing on the existing shaft size to accommodate a reformed arm with a similar wiping pad. The adjustment would be the main sticking point, but that looks a good design.

 

[DMadigan]

A lot of Porsche 911s have been raced with EF adjusters. Have never heard of failures from them.
What is there to fail on a mushroom adjuster? Stock adjusters are too soft. On a long race (which probably does not exist anymore) they could be a problem.
Ball end adjustment screws could be put on the pushrod side of the rockers. The choice is making new rockers or welding/machining the current ones. Moving the screws to the short side of the rockers reduces the inertia. How much money do you want to spend?

 

[Truckedup]

Rocker arm ratios on OHV auto engines are more often than not in the 1.5 to 1.75 range..This avoids using large cam lobes for whatever reasons including easier manufacturing.
My land speed racer Triumph never broke anything, never gets worked on in the pits , I don't even change the jets. It comes off the trailer and does the job. This worked well for the 4 years of this type of racing.The bike makes as few runs as possible to set a new record...I use standard Triumph parts as much as possible.. I stuff I see that fails is often ,but always, after market parts..If it doesn't improve the performance for the situation at hand, it's not changed...I am there for the party and not to get greasy...LOL
On my double engine bike with pre unit engines, I to converted over to lipped seals for the crank end feed oiling.I based this on the crank flex and harmonics of my single engine unit 650 trashing the primary chain.The small bushing sealing the end feed might be trashed at 7500 rpm for 30 seconds during each run down the track..So guess what failed at the track, a seal inverted, lost oil pressure..no damage but sometimes stuff needs to be left alone...Yes, I had three seals, two Pioneer and one other type...A second of inattention during assembly and picked the wrong seal...

 

[TR7RVMan]

Hi, That is a very common system in automotive since OHV motors were developed. I've worked on many motors that used the adjuster on push rod. In real life it don't find it effects valve guide wear. The rocker foot on valve stem wears a dip in the rocker. So feeler gauge doesn't really measure accurately just like our Triumph's stem wears a dip.

Overhead cam motors often had adjuster screw over the valve stem. Mercedes for years had the rocker under the cam... a pivot ball at end of rocker that could adjust up/down for clearance (no rocker shaft), hydraulic lifter. On later motors. This works well, but still the rocker, cam, tip of stem & rocker wear. Clearance is checked between cam & rocker face so divot at end of rocker is sort of compensated for. Diesels had similar, but rocker on shaft. Hmmm.... just like Triumph factory finally went to stelite faced rocker & chill cast cam that was very hard & durable. Each rocker on the Mercedes had spray bar that squirted oil onto cam lobe. 100+ psi hot. The volume of oil is staggering. Oil pumps are huge. Still the volume could not overcome wear.

I followed cam/rocker wear closely for 35 years on hundreds of motors. Thousands actually. The brand/type of oil used made a staggering difference. Easily giving 2-3+ times longer cam wear. Chevron Delo was worst by far. Castrol was 2nd worse. Pennzoil was excellent. Mobil1 Euro was very outstanding in gas motors. It has more zinc than normal Mobil1. For Diesels Shell Rotella was the very best, by a margin. Non chill cast cams with chrome face rockers would easily go 300K+ miles. Chill cast cam with stelite face easily 8-900K miles. Chill cast with Delo 400 often would not cover 200K.
However, in the last 5 years Rotella has changed to many variants. It used to be good for Triumphs. Now many variants have low zinc & friction modifiers... I expect it will make clutch slip. Life is sure complicated sometimes.

Motor wear is a huge subject. So many factors. We just do the best we can. Back when our bikes were built needing overhaul at 35-40k miles or often much less was accepted as normal. Now days that is unacceptable.

My hope is the mushrooms actually improve adjuster & stem tip wear. Truth be told, I'm not too hopeful. If it does, it's back to materials or the mushroom head collects more oil. Franz & Grub sells the same copper plated high quality adjuster in normal tip. Would be interesting to put one on the side & see which lasts longer. That would be the real test.

At the same time.... with the normal adjuster no oil at all gathers on side of adjuster. But mushroom collects oil around top of mushroom even when running. But.... does that oil migrate into rubbing surface, or just fly off?
Don

 

[Truckedup]

Don, I would think that the adjuster should be sacrificial compared to the vave because the adjuster is less expensive and far easier replace..
Shell Rotella T4 15/40 still has about 1200 ppm zinc and is Jaso rated. But it may be a bit thin for a Triumph. It's very popular for Japanese bikes, I use it in the Honda

 

[nala]

Used elephant foot adjusters on my my 66 T Bird for years now , quality parts essential , mine have done a good few thousand miles now with them , really pleased with them , certainly wouldn’t go back to original