HarleyTechTalk

Technical Forums => Shovel Head => Topic started by: Justpassingas on February 22, 2021, 12:16:25 PM

Title: Fork stem thread size question
Post by: Justpassingas on February 22, 2021, 12:16:25 PM
 I have a 69FL that I'm finally putting back on the road. Front end is currently off so I can repack the bearings and the threads on the triple tree fork stem are buggered up a little bit so I'd like to run a die over them. My research says its a 1"-24 thread. Can anyone confirm this before I order a die...thanx
Title: Re: Fork stem thread size question
Post by: capn on February 22, 2021, 03:02:17 PM
If you dont get an answer try measuring 1 inch and count how many threads in that inch.But to me 1/24 sounds right.
Title: Re: Fork stem thread size question
Post by: kd on February 22, 2021, 05:36:25 PM
I don't know the answer but if it was me I would use a thread gauge the check it. They are common and included in most tap and die sets. If I could lay my hands on another stem nut, a few equally spaced 3 corner file grooves full depth of the thread will make a great thread chaser.  A new die will tend to remove material that may just need reforming.  Probably cheaper too and you won't have a die laying around that likely won't be used again.  YMMV
Title: Re: Fork stem thread size question
Post by: Breeze on February 23, 2021, 03:41:24 AM
A thread pitch gauge is a good addition to a tool box. They start at less than $10.
Title: Re: Fork stem thread size question
Post by: Justpassingas on February 23, 2021, 04:12:58 AM
Thanx guys....Thread gauge was my first thought, unfortunately I don't have one but I do have a ton of taps and tried using a 24 & 28 to check the threads. I've used files in the past but would prefer running a die over them but before I do I think I'll just go buy a thread gauge. I tried using a scale and count the treads but its not that easy with a fine thread and these old eyes.  :emoGroan:
Title: Re: Fork stem thread size question
Post by: kd on February 23, 2021, 05:24:20 AM
Just to be clear, I wasn't recommencing you file the thread on the post.  I meant for you to access another nut, used or otherwise, and file across the threads in the fashion of a thread chaser in effect making your own.  Using a die will remove material technically reducing the original rather than reforming it. This is sometimes not advisable because it weakens the clamping strength.
Title: Re: Fork stem thread size question
Post by: Justpassingas on February 23, 2021, 12:30:20 PM
I bought a thread gauge just to be sure and I can confirm it is in fact a 1"-24 thread. I also bought an adjustable die and will back it off so it takes minimal amount of stock off, just enough to clean the threads up so the nut goes on freely.
Title: Re: Fork stem thread size question
Post by: kd on February 23, 2021, 12:46:48 PM
If it's adjustable, can you wind it on past the damage loose, snug it down a bit and run it off in reverse with less risk of cutting the threads? Repeat if necessary.  Just a thought.