Steering head race removal and fitting

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Harry44
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Re: Steering head race removal and fitting

Post by Harry44 »

Have you tried riding it and a bit of heavy front end braking. I've done head bearings on many modern bikes and found they do settle even when they seem to be fully home.
si is does non opportunus vos postulo a maior pango
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Rob Harknett
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Re: Steering head race removal and fitting

Post by Rob Harknett »

REW wrote:Yes Clive, just 28 each race and they feel smooth in operation. I am going to do it all again today (count balls, reassemble yokes) but I do think the discrepancy lies in the two frame races having a different curve on the back, enough to sit slightly proud of the frame cups. Can't see a lot to be done about that other than cosmetic "cures" :(
Am I missing something here???? There is talk of leaving one ball out. I assume so they do not bunch up. Which does happen when you first add the balls in a grease filled race. There are 56 balls, 28 per race, so if you leave one ball out there should only be 27.
Mick D
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Re: Steering head race removal and fitting

Post by Mick D »

Hi Rob

It's a well known rule of thumb that to prevent a 'crowded' race they are designed with sufficient free space to accept another ball, so in this case you could fit 29 but the correct assembly to prevent 'crowding' is with 28 balls as per the parts list.

Regards Mick
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Rob Harknett
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Re: Steering head race removal and fitting

Post by Rob Harknett »

I was not aware of that Mick. So naturally thought, one less would be one less as stated in the parts list. I think some other people have thought the same, as I have found up to 2 less on some of my bikes. I did search everywhere to make sure none had got lost.
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REW
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Re: Steering head race removal and fitting

Post by REW »

I cannot measure the difference in thickness of each pair of races now - I left it too late and the new ones are in place. However, having dropped the stem down again, counted balls etc, a crude caliper measure suggests 0.5mm extra height at the bottom and I suspect slightly more than that at the handlebar lug, adding up to a gap of about 2.5 mm, some of which may have been there originally but I hadn't noticed.

Surface grinding prior to installation would work if you have all races removed, intact and of course machinery to do the grinding dead accurately. I suspect only the yoke races with a flat base could be ground, not the rounded frame races.

I set out to put a rubber washer on top of the upper headlamp bracket ring but managed to dislodge the ring. A slight paint mark shows but on a non - pristine bike barely noticeable. So, I put a fat washer cut from sheet rubber inside the ring, plonked the ring back on the headlamp bracket, offered it all up and now it fits without a gap and looks right. What a bl**dy saga. As nothing compared to the fork seals if you read that thread...
Ron

1951 Matchless G3L thumping round the Durham Dales.
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