OzVMX Forum

Clubroom => Tech Talk => Topic started by: mx250 on May 01, 2011, 01:13:11 pm

Title: Re-Threading Spokes.
Post by: mx250 on May 01, 2011, 01:13:11 pm
I have a number of NOS spokes of various lengths and gauges. I don't have part numbers or model names so re-selling is not a real option. I was thinking of using them by cutting them to length and threading them.

I know this can be done but the threads are normally formed by 'rolling'. I believe this is the way to get a un-weakened thread. Can I use a die cutter to the same effect? Is there any great loss of thread strength using a die cutter.

(http://i323.photobucket.com/albums/nn458/mx250syd/OzVMX/P5010022.jpg)
Title: Re: Re-Threading Spokes.
Post by: AdamN on May 01, 2011, 01:30:06 pm
I 'spose you could work out the lenght you need, then take 'em to someone like Chivo's and get them to roll the thread on the reduced length :-\

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Title: Re: Re-Threading Spokes.
Post by: Christo on May 01, 2011, 01:35:30 pm
No, unfortunately you cannot use a die cutter. If you look at the thread with a magnifying glass you will see that the thread outer diameter is actually larger than the spoke. This is because the thread roller deforms the material, rather than just cuts it.
Title: Re: Re-Threading Spokes.
Post by: cheapracer on May 11, 2011, 01:12:02 am
Yup /\ don't do it unless you can match the nipple size accordingly.

hehe, I said nipples, hehe.

Title: Re: Re-Threading Spokes.
Post by: yamaico on May 11, 2011, 04:10:26 am
Hi Graeme,
The reason the thread is rolled is because it becomes larger in diameter than the spoke. This enables the nipple to go past the unthreaded part of the spoke, allowing for more adjustment as well as containing the shear point at the end of the thread within the nipple. Additionally, the spoke is stronger at the thread because the root diameter has not been reduced, as opposed to normal thread cutting. Hunt around on ebay and see if you can buy a spoke rolling tool. I have one at home and make all my own spokes - very handy.
Pete.
Title: Re: Re-Threading Spokes.
Post by: montynut on May 11, 2011, 06:58:51 am
Graeme,
I think you posted previously that they are Montesa spokes? It may be worth taking some spokes to a Gas Gas and/or Sherco dealer as I have been told that one uses spokes threaded to the old metric gauge standard. Well I have been told that they are compatible with Bultaco spokes which I believe are the same as Monty spokes. It would be worth a try. I have been meaning to check as I also have a large number of Monty spokes but the same as everyone no nipples :(.
Title: Re: Re-Threading Spokes.
Post by: mx250 on May 11, 2011, 08:24:46 am
Hi Graeme,
The reason the thread is rolled is because it becomes larger in diameter than the spoke. This enables the nipple to go past the unthreaded part of the spoke, allowing for more adjustment as well as containing the shear point at the end of the thread within the nipple. Additionally, the spoke is stronger at the thread because the root diameter has not been reduced, as opposed to normal thread cutting. Hunt around on ebay and see if you can buy a spoke rolling tool. I have one at home and make all my own spokes - very handy.
Pete.
Thanks Pete for a comprehensive and informative reply. I've already done a couple of Ebay searches.

Graeme,
I think you posted previously that they are Montesa spokes? It may be worth taking some spokes to a Gas Gas and/or Sherco dealer as I have been told that one uses spokes threaded to the old metric gauge standard. Well I have been told that they are compatible with Bultaco spokes which I believe are the same as Monty spokes. It would be worth a try. I have been meaning to check as I also have a large number of Monty spokes but the same as everyone no nipples :(.
These are Yammy spokes Monty - I'm not exactly sure from what. Probably YZ/WR250F, XT's and DT175's.

I found some suitable nipples for the Monty stainless spokes. I think they are early Ducati nipples but am unsure. They are a different thread to Bully's.