Rocker spindle misaligned.

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komet

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I'm in the process of fitting NYC one piece rocker spindle covers to my '71 Commando. Removed RHS exhaust ones and found the spindle had rotated about 1/8th of a turn. Is there an easy way to tell if the flat is facing the front? And if I use a hot air gun to heat each end, will this be sufficient to turn it?

Thanks,
Graeme.
 
L.A.B. said:
Try using a piece of wire with a short right-angled bend inserted into the rocker spindle to locate the position of the feed hole.



Probably.
Click to expand...
Toast 'er up but good and try to move it back into proper place with a big screwdriver into the slot .
 
If it was no longer held in place by the stock spindle cover, I would pull it and check its condition, but that is just me. They don't move that easily out of place once installed. Might have seized a little at some point and be scarred. Something moved it, or it was not installed aligned with the cover in the first place.
 
It could be that it is a loose fit into head at inboard end. This would allow it to rotate a little out of dead horizontal end slot. I have one that is a bit loose, likely from a Dreaded Previous Owner pulling it out without proper pre-heating. Will be putting a bit of locktite bearing goo on inboard end next time it is out.
 
I recall someone (Jim?) reducing the bore of a worn outer spindle hole by doing something like bolting through 2 sockets (one inside, one outside and then.... damn, can't remember.
I do remember thinking at the time that it was a clever idea!
I will edit and update if I remember.
Cheers

Someone else chime in if you recall please.

Found it - and it was Jim... Dec 8, 2011
Kudos to @comnoz !
 
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This is not a derail - although some may argue.
I have a similar problem with the original (matching number) crankcases for my 650ss. I have bought an orphan set as an interim measure.
The fit for the main bearing outers on the originals are loose.
I intend to do what some racing cars do with their mag wheels when the bearings come loose. Apparently some teams (Porsche) knurl the bore then use a loctite to fill the grooves before pushing the bearing in. I have a jig made up from 4, slightly blunted, pipe-cutting wheels.
My plan is to set it up in a mill and roll grooves in the bores, causing the alloy to "upset" and reduce the bore.
I'll post info when I do it.
Cheers
 
That sounds horrible to me Rob !

If you have access to machining facilities, then the correct repair is surely to sleeve the cases.

An alternative old school fix is to get the bearings copper plated to increased the OD.
 
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Fast Eddie said:
That sounds horrible to me Rob !

If you have access to machining facilities, then the correct repair is surely to sleeve the cases.

And alternative old school fix is to get the bearings copper plated to increased the OD.
Click to expand...
The conundrum is the integrity of the sleeve. There's not much room to make a sleeve of any substantial strength, and it will have to be interference fit in the case with a good transition fit for the bearing.
I has been 6 years since I last examined options.
I will go through it again.
Cheers
 
Loctite does not work with a steel bearing in an aluminium housing, the heat cycles degrade the Loctite and it breaks down into small pieces, which I found in the sump. As FE suggests if a sleeve will leave too little base material then copper plate the OD of the bearing, they did this all the time in the factory I worked in. Its only a few thou thick and is strong enough in compression but soft enough to thin using emery cloth if its too thick. You are looking for a 1.5 to 2 thou interference fit.
 
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Thanks for all the replies. Decided to remove head as all spindles were nearly 180 deg out and hot air gun wasn't hot enough. Found exhaust valve guide loose in the head and 2 tappets fitted back to front. The guide is worn internally too, so hopefully that explains the oily plugs and exhaust port.

The previous owner had seized the motor due to a broken oil line and had a full rebuild done by a bike shop, new barrels, pistons, bearings, etc. Found head nuts upside down, metal swarf in the pressure relief valve, as well as a surprising amount of metal in the bottom of the oil tank. Did run and sound OK so think it just wasn't cleaned out properly. So much for a 'professional' $6000 rebuild.
 
I have a small "knocker" that was designed to remove advance plate from cam. It works great for removing rocker spindles, of course after a little heat!
 
Finally started on mods to rocker spindle covers for my 650ss - has loose-ish spindles.
I bought a set from Eurotrash and am doing a mod similar to RGM except with 2 grub screws - I think this will prove better, more even locking.
I am not going to replicate the large RGM cover nut but will lock and seal the grub screws with loctite 577. Also does not look so "obvious".
In the photos below I have not yet shortened the screws - they will end up about 8-10mm long.
Rocker spindle misaligned.Rocker spindle misaligned.Rocker spindle misaligned.Rocker spindle misaligned.
 
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I have always thought what a piss poor idea the rocker spindle set up is on the Norton twins. Why the hell Hopwood didn't fit eccentric spindles as Phil Walker did on the AMC twins I'll never know. I believe Doug Hele did this on the Domiracer motors.
 
robs ss said:
Finally started on mods to rocker spindle covers for my 650ss - has loose-ish spindles.
I bought a set from Eurotrash and am doing a mod similar to RGM except with 2 grub screws - I think this will prove better, more even locking.
I am not going to replicate the large RGM cover nut but will lock and seal the grub screws with loctite 577. Also does not look so "obvious".
In the photos below I have not yet shortened the screws - they will end up about 8-10mm long.
View attachment 108140View attachment 108141View attachment 108142View attachment 108143
Click to expand...
take care that the inwards grub screws do not block the oil path from the rocker feed, may be that's why RGM only put the outwards grub screw hole
 
Hmm. My Atlas w/commando head of unknown source has slipped one spindle enough so that the cover was leaking oil, maybe 15 degrees. Whether I did this or I installed a complete head, I don't remember. In any case how far rotated can the spindle be without blocking oil passages?
 
Thomasa said:
Hmm. My Atlas w/commando head of unknown source has slipped one spindle enough so that the cover was leaking oil, maybe 15 degrees. Whether I did this or I installed a complete head, I don't remember. In any case how far rotated can the spindle be without blocking oil passages?
Click to expand...
The oil feed on the head looks to be about 4mm diameter and the slot in the end of the spindle is also 4mm wide, so it will begin blocking with any rotation.
The spindle diameter is about 12.7mm so the circumference is about 40mm.
4mm rotation will completely block the feed which is 0.1 x circumference - so 36 degrees.
Your 15 degree rotation would be a bit less than half blocked.
Cheers
 
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