Rear Sprocket Bolts and nuts

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
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mattward
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Rear Sprocket Bolts and nuts

Post by mattward »

Hello Folks,

I had a couple of questions regarding the 6 bolts, washers, and nuts holding on the rear sprocket. I have read this post and it sort of doesn't help my questions - viewtopic.php?f=15&t=25146&sid=bc97749d ... b&start=10

Firstly I think I made yet another rookie mistake, I put washers on the outside of the sprocket as well as on the inside of the sprocket fixings, this is what I think likely lead to my maiden journey of length shedding 4 of the 6 fixing without my knowledge, very lucky I made it home me thinks.

I have looked into purchasing more genuine (or close to) bolts and nuts and they are nowhere to be found. I have a possible solution, which I would appreciate some feedback on if possible. I can buy 1/4" X 5/8" bsf/bsc 26tpi fixings but only as set screws, either hex or Allen heads. My question is, does anyone think the shank on the standard bolts is completely necessary?

I am very wary of the potential slack created by a completely threaded shaft compared to that of a shank, which is why I am a bit concerned. I would however this time be using 'Red Threadlock' which was another oversight from the first assembly. Do you think this would be good enough to do the job?

Obviously, I would rather not call my dearest to come collect me due to a repeat of the above experience completely occurring... Any thoughts would be greatly appreciated, thanks in advance.

Cheers
Matt
Andy51
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Re: Rear Sprocket Bolts and nuts

Post by Andy51 »

They are NOT 1/4 by BSF/BSC, they are BSC only, both threads have 26 tpi but the thread angles are different and BSC will not properly tighten in a BSF threaded hole. I would say the plain shank is important as there will be fretting against the threaded portion as it is marginally smaller in diameter than the plain length, and has less bearing surface. I would go for high tensile 1/4 in bolts, which I believe are obtainable in long lengths, with a plain shank at least as long as the standard AMC bolts. You can then re-thread them 1/4 BSC, length as per the original, but you must do this on a lathe to ensure the thread is truly square. Andy
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mattward
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Re: Rear Sprocket Bolts and nuts

Post by mattward »

Hi Andy,

Much appreciated feedback. The thread angle is an interesting point I had not considered as BSC being 60 degrees and BSF being 55 degrees is quite different. Thankfully at this stage the only 1/4 BSF I have used have been with matching nuts so no harm done. Even getting 1/4 BSF is a mission down these ways. I will take your advice and purchase some longer bolts (they will be allen heads as reduced heads bolts not available) with shanks long enough to thread myself. The nuts are sorted. Thanks for the advice, I will post whether or not they work over time once installed and in use for a few rides, fingers crossed!!!
Cheers Matt
Red Gauntlet
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Re: Rear Sprocket Bolts and nuts

Post by Red Gauntlet »

See: viewtopic.php?f=15&t=28772 in the end I used the Villers ones and put a bit more thread and nylocks, so far so good.
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mattward
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Re: Rear Sprocket Bolts and nuts

Post by mattward »

Hi Max,

Thanks very much for the heads up that there are alternatives. I managed to find a Triumph part (NZ stock) which looks the same as the ones you got from Villiers, by all accounts they will be a bit long and need a bit of threading up the shank, but thats a great win I reckon. I also managed to find the correct locknuts from an Australian stockist too, so all should be excellent. I did not think that local(ish) stockists would be able to come through...
https://www.britishmotorcycleparts.co.n ... ults&gp=21
https://www.classicbikespares.com.au/pr ... t-1-4-cei/

Many Thanks, Matt
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