Front anchor stay fixing

Information relating to the Matchless G9 or AJS Model 20 500cc twin
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JayP
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Joined: Sun Dec 08, 2013 8:44 pm
Location: UNITED KINGDOM

Front anchor stay fixing

Post by JayP »

Hi,
Just rebuilding the front wheel and have noticed that there is barely any thread left on the brake cover plate for the anchor fixing and it allows the bolt to push down and won't retain. As this is steel insert is there a replacement item in Jampot spares? Or would a helicoil be a good way to proceed?

What is the size of the fixing bolt 3/8"? It doesn't seem to be a cycle thread by counting the number of threads.

Thanks
Jason
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dave16mct
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Location: LANCASHIRE UK

Re: Front anchor stay fixing

Post by dave16mct »

If I were you I'd find another brake plate. That fixing has to be perfect, anything less could be dangerous. The standard bolt is 3/8" cycle, I suppose an option could be to drill and tap out to a slightly bigger size. Just make sure it's a good high tensile bolt in a good thread.
Dave.
JayP
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Joined: Sun Dec 08, 2013 8:44 pm
Location: UNITED KINGDOM

Re: Front anchor stay fixing

Post by JayP »

Hi Dave,
Thanks for the bolt info.

Finding another brake plate would probably be the best option. So if anybody has one for sale on this forum for a 1955 model please let me know (with good thread of course :P ) Please use either the advertisment section of the website of the adverts section of the forum for Wanted ads Adverts Editor

If I can't find one then may have to look at the other option. I would prefer not to go that route as I understand the safety aspect.

Ta.
Mick D
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Location: Aberdeenshire

Re: Front anchor stay fixing

Post by Mick D »

Hi

If it is a steel top hat bush just press it out, get a new one made to match, (easy task for anyone with a lathe), press the new one in with a bit of bearing fit for added security.

Regards Mick
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clive
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Location: LONDON UK

Re: Front anchor stay fixing

Post by clive »

I would be cautious about drilling and taping to a larger size as it will entail a bigger hole in the brake anchor stay, admitedly only small but there is not a lot of metal on them at the best of times.
clive
if it ain't broke don't fix
raffles
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Joined: Mon Jan 01, 1990 12:00 am
Location: NORTHAMPTONSHIRE UK

Re: Front anchor stay fixing

Post by raffles »

there is plenty of metal in the modified stay
Andy51
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Re: Front anchor stay fixing

Post by Andy51 »

I think you'll find the bush is cast in place so replacing it is a non-starter. Given the critical nature of this joint, helicoiling is unlikely to be good enough and drilling out for a larger bolt would weaken both bush and stay. I often see these backplates at Kempton, and they are cheap enough. Get another one is my advice. Andy
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dave16mct
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Location: LANCASHIRE UK

Re: Front anchor stay fixing

Post by dave16mct »

OK , found out today, it's not a top hat bush, nor is it cast in. It's threaded in. I was looking for a brakeplate and the one I wanted had a big threaded hole where the stay should fix. I found a very tatty one which had been tastefully drilled for racing?...... I locked a bolt in it and unscrewed it. Then screwed it into the good plate.
Dave.
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