Bugger .... just had the top yoke crack

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Richard
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Joined: 24 Aug 2017, 14:35
Location: Zeewolde NL
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Re: Bugger .... just had the top yoke crack

Post by Richard »

Must have been a great ride. It will be months before I'm able to, winter finally arrived with lot's of fog and below zero temperatures, not my favorite period of the year... :cry:
Monty9120
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Joined: 05 Jan 2018, 13:04

Re: Bugger .... just had the top yoke crack

Post by Monty9120 »

I had the same happen to me

How much pressure is the top clamp actually under?

I used some thick washers on mine but the bikes off the road anyway
Freddy
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Joined: 06 Sep 2017, 11:06
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Re: Bugger .... just had the top yoke crack

Post by Freddy »

Monty9120 wrote:I had the same happen to me

How much pressure is the top clamp actually under?

I used some thick washers on mine but the bikes off the road anyway
Had the original welded up for the ride, and to be perfectly honest it was probably stronger than original as I'd told the welder I don't want it pretty, just strong so build it up. Anyhow since than I bought a new one and replaced the welded one with it.

I no longer torque the top yoke, just do it up by feel to what I think appropriate. The irony is the only time I've ever broken parts or had bolts break was when using a torque wrench.

I can't remember how much I paid the welder to repair the yoke, think it was something like $30. It was easy to accurately position the creaked off piece for welding using the retaining bolt to hold it in the correct position.
gazzz
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Re: Bugger .... just had the top yoke crack

Post by gazzz »

That clamp of top yoke is weak place of Zephyr 750. The same happened with top yoke of my Zephyr years ago, as well as with top yoke of another Zephyr 750 in Ukraine. And like Freddy, I broke mine using a torque wrench. :D

I rode my motorcycle with welded top yoke for the years and replaced it only last year.
tr_004.jpg
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Richard
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Re: Bugger .... just had the top yoke crack

Post by Richard »

Thanks for the warning guys, am about to do some work on these parts, in dutch "a warned man counts for two"...
Freddy
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Re: Bugger .... just had the top yoke crack

Post by Freddy »

gazzz wrote:That clamp of top yoke is weak place of Zephyr 750. The same happened with top yoke of my Zephyr years ago, as well as with top yoke of another Zephyr 750 in Ukraine. And like Freddy, I broke mine using a torque wrench. :D

I rode my motorcycle with welded top yoke for the years and replaced it only last year.
tr_004.jpg
Thanks for the info Gazz, its good to know I'm not a complete dickhead for breaking it.

Seeing I'm recommending doing something up less than manufacturers recommended tension, I'd hate to see someone's forks slip in the yokes because the yokes were loose so should clarify .....

The bottom yoke with the 2 retaining bolts is made of steel. It should be tensioned up to the manufacturers specification of 14.5 ft/lbs using a quality suitable size tension wrench. There is no stretch in this clamp, the bolts just snap up to tension like a normal bolt or nut. I reckon there's enough 'clamp' in the bottom yoke alone if correctly done up that the forks will never slip. The top yoke being made of aluminum stretcheeeeeeees as you pull up the bolt. The bolt or thread doesn't fail, its the thin bit of the yoke. I think its the constant stretching as the bolt is done up and undone that causes the yoke to eventually fail. So just do it up snug and firm enough by hand so that it won't undo, and minimize the amount of stretching of the yoke clamp.
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