easy fix for rotating rocker shafts. (2014)

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kerinorton

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Some years ago, I developed an oil leak from the l/h exhaust rocker spindle gasket. I fixed it in a hurry but had to do it again and that's when I realised the tags on the plate were not engaging with the rocker shaft. I also discovered there is one hell of a large flat ground into the shaft as well [ far too much in my opinion as I have never seen much more than holes in shafts on the cars I have worked on over the years ], so it would do a lot of damage if it rotated too far.
I got a compression spring out of my supply box , shortened it the fitted it in prior to refitting the shaft. Easy and cheep fix. [ note the length was just short of binding, so it could not possible let the shaft move.]
 
RGM sell a set of special stainless end plates with screws not tabs to hold loose rotating rocker spindle. I think they are around £100 plus VAT (only if your in UK) and postage.
They look good and will save have to remove the head an have machining other metal spraying type repairs done which would cost far more i reckon.
Of course am sure someone will have a cheaper fix that will most likely involves JB weld☺
 
They were cheaper than i though thankyou the ever helpful LAB.
My own spindles are a good fit but like yours are to far in so i my use these myself just for piece of mind.
 
Mick Hemmings sells (or at least, used to sell?) some alloy one-piece items, and those had longer tabs.

However, a spot of MIG weld and a bit of filing would probably fix the plate and save £48.99 (plus the VAT).
 
kerinorton said:
I got a compression spring out of my supply box , shortened it the fitted it in prior to refitting the shaft. Easy and cheep fix. [ note the length was just short of binding, so it could not possible let the shaft move.]
Click to expand...

I did that to mine about 3 years ago when I was building my 74' back up. Went to the local Ace Hardware store, got a spring and shortened it up to fit behind the rocker shaft and then with a punch bent out the tabs to engage the shaft.
I should have replaced the spring washer with a solid set of shims. I think it would reduce the valve noise.
 
Guido said:
kerinorton said:
I got a compression spring out of my supply box , shortened it the fitted it in prior to refitting the shaft. Easy and cheep fix. [ note the length was just short of binding, so it could not possible let the shaft move.]
Click to expand...

I did that to mine about 3 years ago when I was building my 74' back up. Went to the local Ace Hardware store, got a spring and shortened it up to fit behind the rocker shaft and then with a punch bent out the tabs to engage the shaft.
I should have replaced the spring washer with a solid set of shims. I think it would reduce the valve noise.
Click to expand...

Theoretically the Thackeray washer reduces the noise...

Racers use solid because they don't care that much about the noise, or the time it takes to measure gaps and shim to fit.
 
SteveA said:
Guido said:
kerinorton said:
I got a compression spring out of my supply box , shortened it the fitted it in prior to refitting the shaft. Easy and cheep fix. [ note the length was just short of binding, so it could not possible let the shaft move.]
Click to expand...

I did that to mine about 3 years ago when I was building my 74' back up. Went to the local Ace Hardware store, got a spring and shortened it up to fit behind the rocker shaft and then with a punch bent out the tabs to engage the shaft.
I should have replaced the spring washer with a solid set of shims. I think it would reduce the valve noise.
Click to expand...

Theoretically the Thackeray washer reduces the noise...

Racers use solid because they don't care that much about the noise, or the time it takes to measure gaps and shim to fit.
Click to expand...

There you go. One less thing to worry about.
 
As LAB suggests, you can TIG a small tab onto either the inner punched plate or outer solid plate, and file to fit in the end of the spindle, if you use the outer solid plate to TIG the tab on, you do away with yet another gasket, down to one instead of 2.
have done this on both of my bikes.
I have seen mods where racers have modified the outer plates to take a banjo fitting, linked all 4 x banjo fittings together in series with tubing, use the normal feed line from the crankcase to feed the first fitting. Blank off the 2 x original banjo bolt holes in the head., the new feed system goes directly down the spindle into the rocker and rest of valve gear , has quietened the valve clatter as well.
Regards Mike
 
Mine isn't noisy. The modification shown made by Sir Ed looks good though. When you live in the boondocks, you have to make do with what is available. My spring loaded semi solid spacer seems fine right now. This bike gets ridden a lot when the weather is ok.
Dereck
 
I recently discovered the same problem, I. e., rotating rocker shaft/spindle which migrated too far in to engage with the tabs. This is on a new Fullauto head. Will try to shim the shaft and move it out a bit so it matches the two locating tabs on the cover plate. I assume I can do this (CAREFULLY) without taking the head off. Any opinions as to shim type? Spring vs. solid spacer? I suspect I'll need about 2mm or so.

Thanks.
 
John B in Bama said:
I recently discovered the same problem, I. e., rotating rocker shaft/spindle which migrated too far in to engage with the tabs. This is on a new Fullauto head. Will try to shim the shaft and move it out a bit so it matches the two locating tabs on the cover plate. I assume I can do this (CAREFULLY) without taking the head off. Any opinions as to shim type? Spring vs. solid spacer? I suspect I'll need about 2mm or so.

Thanks.
Click to expand...

Assuming you have one piece caps, I might instead relieve the head facing surface on the mill to gain the additional depth required for the tangs to engage. Failing that, I'd just mill a new set with deeper tangs.
 
acadian said:
Assuming you have one piece caps, I might instead relieve the head facing surface on the mill to gain the additional depth required for the tangs to engage. Failing that, I'd just mill a new set with deeper tangs.
Click to expand...

I don't think milling the head to solve for the recessed rocker shaft would be ideal. A spacer behind the shaft, a longer shaft or a deeper plate seems like better options.
 
For a long time I make and sell the plates in Aluminium with a higher tang to securely lock the shafts in the correct position. Every engine that I rebuild gets these parts because it only needs one gasket and looks much better than the lousy steelplates with two gaskets.
 
swooshdave said:
I don't think milling the head to solve for the recessed rocker shaft would be ideal. A spacer behind the shaft, a longer shaft or a deeper plate seems like better options.
Click to expand...

Not the head, the caps

WEAL Norton said:
For a long time I make and sell the plates in Aluminium with a higher tang to securely lock the shafts in the correct position. Every engine that I rebuild gets these parts because it only needs one gasket and looks much better than the lousy steelplates with two gaskets.
Click to expand...

yes, like this
 
Guido said:
I did that to mine about 3 years ago when I was building my 74' back up. Went to the local Ace Hardware store, got a spring and shortened it up to fit behind the rocker shaft and then with a punch bent out the tabs to engage the shaft.
I should have replaced the spring washer with a solid set of shims. I think it would reduce the valve noise.
Click to expand...
The SS-clone has shimmed rocker shafts and that actually increased valve train noise.
 
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