alternate rocker thrust washer

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fireflake

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Does anyone know if there are spacers available to replace the thrust/thackery washers for the rockers, thanks
 
I had some made for me using Aluminium Bronze but buying off the shelf today,not not that I know of.A very long ago Unity Equip in the UK used to sell them as set of four for Triumphs,not sure if the ID is the same as a Norton rocker shaft.
You could have some made all a bit over size and grind them back to fit.No big deal.
Where are you in OZ?
Brett
 
They look very neat, but just curious as to what advantage they give?
 
Gilesy said:
They look very neat, but just curious as to what advantage they give?
Click to expand...

Less power lost to friction, and positive location of the rocker arm. Not sure how significant either of those advantages are. I've used the RGM kit, and it works well, but in most cases I just use the stock springs, and stack washers to center the tip of the rocker arm on the valve stem.

Ken
 
I’m Comnoz’ spintron thread he mentioned the benefits of having a ‘dampener’ in the valvetrain system.


Does the spring perhaps provide some such dampening?
 
Ken, how much clearance did you give when you used washers no spring?
 
I am surprised the RGM spacers are made of brass. Though brass does come in varying hardness. If I were making them it would be out of bronze.

Stephen Hill
 
Stephen Hill said:
I am surprised the RGM spacers are made of brass. Though brass does come in varying hardness. If I were making them it would be out of bronze.
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"Bronze" according to an old RGM paper catalogue.

Also on RGM's old webshop page: http://www.rgmmotors.co.uk/main.htm >Catalogue>Top End [2/5]

"56 050020 0.133" THICK BRONZE ROCKER SPINDLE THRUST SPACER"
 
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Fast Eddie said:
No idea, they could be bronze for all I know...
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They were listed by RGM for many years as "bronze".

The Norvil thrust washers (and the ones sold by Mick Hemmings) are described as "bronze" so I think "brass" is probably an error.

http://www.norvilmotorcycle.co.uk/
"069506 WASHER - THRUST - ROCKER SPINDLE - BRONZE - FOUR REQUIRED - NORVIL"

http://www.mickhemmings.co.uk/cat/PriceList.pdf
"BRONZE ROCKER SPINDLE THRUST WASHERS (SET 4) ..............................TXK 026"
 
Onder said:
Ken, how much clearance did you give when you used washers no spring?
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No particular clearance spec. I bought packages of 3/4"x1/2" stainless steel shims in .015", .020", and .031" thicknesses, and just fitted them along with the bronze spacers and some original shims to get the rockers centered on the valve stem, with as little clearance as I could get with those shims and still have free rotation of the rocker.

Ken
 
fireflake and onder

Gidday mate, I,ve always used bronze spacers on the inner sides of the rockers and steel shims on the outers to centre the rockers with a clearance of around 0.005"

Both types are from RGM and the bronze spacers set the alignment but have always needed customising to centre the rocker on the valve.
I hand lap them to size on a small surface plate with 150-240 wet n dry checking thickness with a micrometer and doing each rocker individually until all are central.
Steel shims are added on the outer side and clearance adjusted to the final 0.005" with the excellent AN allen key mushroom adjusters central on the Black Diamond valve stems.
Before starting, smooth the rocker end faces and chamfer the edges to remove any sharp points left by the Thackereys, the depressions are OK, probably help lube.

Easy and accurate valve clearance adjust and no problems to date with minimal wear on valve stems compared to the old style spring and standard adjuster setup I inherited with the bike.
Another home brewed task needing patience and attention to detail but light on cost and high on job satisfaction when it,s done.
 
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I did this a few years ago when I lived in the long cold New York State winters. As you say it takes time and attention to detail. But think it worth
it for being able to centre the rocker on the valve alone.
 
I use bronze spacers with zero clearance and a slight amount of friction .
The expansion of the head will loosen them up .
 
lcrken said:
No particular clearance spec. I bought packages of 3/4"x1/2" stainless steel shims in .015", .020", and .031" thicknesses, and just fitted them along with the bronze spacers and some original shims to get the rockers centered on the valve stem, with as little clearance as I could get with those shims and still have free rotation of the rocker.

Ken
Click to expand...

Hello ,
That's exactly the way to go. You may need to center the rocker to the top of the valve. It may add a bit of mechanical noise because of a bit of backlash to pthe rocker. I do the very same thing when I do my big valve conversions.
The only question is: Does the rocker really need to touch the valve top in the center? If it touches it off center, the valve might rotate, which would be good for the wear of the sealing surfaces. But that 's theory.
Best Regards
Klaus
 
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