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Author Topic: Repeated Top yoke breakages  (Read 1094 times)

Offline paulbaker1954

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Repeated Top yoke breakages
« on: March 23, 2017, 03:23:23 PM »
Help
I have now had 2 top yokes break in one year. The first time I pit it down to me forgetting to tighten it up but now I have just had another one break

Fracture occurs on the right hand fork side at the rear of the bracket

Forks are true, no looseness in steering head, handles perfectly and jus MOTD

What is going on ?
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If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline mickwinf

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Re: Repeated Top yoke breakages
« Reply #1 on: March 23, 2017, 03:32:14 PM »
have you fitted the special thick washer in the gap to prevent over tightening?
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Offline Trigger

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Re: Repeated Top yoke breakages
« Reply #2 on: March 23, 2017, 04:14:34 PM »
D washer spings to mind
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Offline paulbaker1954

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Re: Repeated Top yoke breakages
« Reply #3 on: March 23, 2017, 04:41:27 PM »
Aha that explains it then👌👌👌

When I got the bike these must have been missing, I see them now on the parts list

Do I need to buy them ad special washers i.e. Does anyone know the thickness so I can use a std washer of that thickness?
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If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline deltarider

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Re: Repeated Top yoke breakages
« Reply #4 on: March 23, 2017, 04:42:08 PM »
D washers or use the 7mm bolts as used on the CB500/550 K2 '76. Honda had a reason for this modification...
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Offline Chris400F

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Re: Repeated Top yoke breakages
« Reply #5 on: March 23, 2017, 05:09:20 PM »
Found this which should help: http://www.sohc.co.uk/index.php?topic=9241.0
« Last Edit: March 23, 2017, 05:19:33 PM by Chris400F »
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Offline paulbaker1954

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Re: Repeated Top yoke breakages
« Reply #6 on: March 23, 2017, 05:18:22 PM »
Ordered from DS to be safe

Bit steep at 5.50 each but better than another yoke in the future!!!
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If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline Seabeowner

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Re: Repeated Top yoke breakages
« Reply #7 on: March 23, 2017, 05:25:41 PM »
I found the washers on the head studs are as near a dammit. But used my 500 in ignorance for a few years. Perhaps I'm just a weakling.
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Phil
1971  CB500K0  Candy Jade Green or Candy Gold
1973  CB500K1  Candy Ruby Red
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Offline Tomb

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Re: Repeated Top yoke breakages
« Reply #8 on: March 23, 2017, 05:55:35 PM »
I learn something new every day on here, I have no washers in my yoke, owned it for 32 years and didn't know. No other bikes I've ever owned have these type washers, I guess I tighten them just the right amount not to cause breakages
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Tom
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Offline deltarider

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Re: Repeated Top yoke breakages
« Reply #9 on: March 23, 2017, 06:16:06 PM »
Quote
I have no washers in my yoke, owned it for 32 years and didn't know.
What model year?
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Offline paulbaker1954

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Re: Repeated Top yoke breakages
« Reply #10 on: March 23, 2017, 08:55:32 PM »
Mines a 71 USA Spec  K0
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If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline royhall

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Re: Repeated Top yoke breakages
« Reply #11 on: March 24, 2017, 08:07:19 AM »
Cant add anything but Crikey, the amount of Honda knowledge on this forum is stunning. Where else would you find detailed information like that. Well done guys.
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Offline paulbaker1954

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Re: Repeated Top yoke breakages
« Reply #12 on: March 31, 2017, 01:27:36 AM »
Lady luck has blessed me !!

The day the yoke fractured i got a replacement off fleabay auction for £15 (i was only bidder). The seller was in York is this a member here??

Hopefully with my outrageously expensive D washer from DS all will now be sorted
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If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0
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