Head race fit

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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Pharisee
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Head race fit

Post by Pharisee »

I'm in the final stages of dismantling my '55 M18S and have just removed the top steering yoke. I was a little surprised to find that the two bearing tracks that are in the frame were a very loose fit... like a pound of sausages up the Blackwall Tunnel!!
From my experience with my older Triumphs that use loose ball bearings in the steering head I had expected to have to tap the bearing tracks out of the frame. Is that correct or has someone put incorrect bearings in at some point in the past?
John
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1608
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Re: Head race fit

Post by 1608 »

I believe they are correct and called floating cups.
Mick D
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Re: Head race fit

Post by Mick D »

Hi

The bearing races are located by their spherical, (torroidal actually), surfaces and as such are not a tight fit into the frame, mine could be lifted out and replaced with a finger only. That said the difference in OD of the race to ID of the headstock was only a few thou.

Regards Mick
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Pharisee
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Re: Head race fit

Post by Pharisee »

Mick D wrote:Hi

That said the difference in OD of the race to ID of the headstock was only a few thou.

Regards Mick
I probably exaggerated the looseness just a little. :oops:
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spookefoote1956
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Re: Head race fit

Post by spookefoote1956 »

1608 wrote:I believe they are correct and called floating cups.
A bit like throwing sausages down the mersey tunnel.
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