Topic: How to Restore the Internal Threads in Your Wheel Hubs

[dagersh]

I recently read a post on using an Impact Driver for those who are doing things to their bike for the first time.  Not so long ago, I had never even picked up a wrench to work on a motorized vehicle.  As I have been involved with my bikes I have slowly gained the confidence to delve deeper and deeper into repairs and restorations.  I give the major majority of this new found confidence to this excellent forum.  This is all to say that this post is for anyone who has any doubts in their ability to accomplish the following task.
I would think a common problem we might run into post drilling out the punch marks that the factory used to keep our Wheel Bearing Retainers from back out.  These retainers, especially the front one, can be very delicate, and the threads even more so.  I ran into this problem when removing my retainer, and I really bunged up my threads.  I thought I had cleaned them up really well, but when I went to screw the retainer back in, it got cross-threaded and really messed up the threads (and destroyed my original retainer – ooops!!!) 


The Original…




The messed up threads

So my question was, how do clean these up so that I won’t kill another retainer?  I ordered a new retainer and seal (messed up the seal beyond repair with the original retainer).   I posted the question to the board.  I got several good answers, but the one that made the most sense was from 754.

Thread file wont do internal..

 Try this, find a sharp tap of same pitch.. size, not important..
 Now hold it tight in a tap holder, and pesent 1 flute to the threads, get the tap into the good part, and with leaning or light pressure work around the damage, trying not to take any off the good thread..
...good luck..

So, I went at it.  It works great!  I took a Metric Tap whose pitch matched the damaged threads.  I double checked the pitch against the new retainer.  I then carefully went over the damaged thread with the Tap.  To do this, I found an undamaged starting point where the threads of the Tap were flush with the undamaged thread in the Hub.
I then carefully went around the circumference of the hub surface using moderate pressure, so that the Tap would “cut” away the damaged thread.  I must have done a lot of damage, as I took off a bunch of metal.  I was careful to check my progress as I went along.  I would use a brass brush to remove the larger loose metal that was removed, and then I would use some PB Blaster and a rag to really clean the threads up.  I would then take the new retainer and lightly screw it in.  If I hit any resistance, I would back it out and continue to clean up the threads.  I repeated this until the retainer screwed in and out smoothly.

The Tap I used is on the left

In like Flynn!
Hope this helps guys!!!

[timdhawk]

All I can say is thanks for nothin!!!!!
Where was this thread 1 month ago when I had to throw away a freshly powdercoated hub and get another one and have it powdercoated again because of this exact issue???

Way to be on the ball there fella!!!!




 
Seriously though...good info! thanx!!!

[dagersh]

I am on a month dealy......

[BobbyR]

Great Work! Now you another another skill.

[dagersh]

Oy, don't rush me!

[fastbroshi]

  I'm not following how you did this.  Did you just hold the tap in your hand like a butter knife scraping the top of the Country Crock?

[dagersh]

FB,

I made sure that the Tap was flush in with good grooves, and carfully rotated the hub while applying pressure on the tap.  The blades on the tap will reset the the damaged grooves. 

I wish I coudl explain it clearer than that.  Once you have everything in your hand, it will make much more sense.

Gersh

[fastbroshi]

Let us know when you come up with a new cnc'ed hub design with out that god awful retainer.

[dagersh]

Your faith in my ability to do that is.....  disturbing!

[fastbroshi]

I was being sarcastic  ; yeah I was following you, just had a hard time believing it would work so easy.  Ya know?

[wingman]

Thanks for this tip.  The PO of my bike made a mess of the threads and this really saved me from having to buy new hubs.  Gracias.

[754]

 fastbroshi

 You can probably run without it, Kawasaki does, and Morris wheels as well.. but it would look funny on there..

 That powdercoated hub, no matter how bad, you can probably fix it on a lathe or recut and make a bigger retainer..

[Steel Dragon Performance]

I have used thread files that way on the out side of bolts . I think that's a great tip for for inner threads thanks.     

[fastbroshi]

754:

DAMMIT DOES EVERYBODY HAVE A LATHE BUT ME?!!! LOL Okay I had to put that out there.  Every time I turn around someones machining and carving this or that. I really need to get one and just start carving up random stuff.   Seems like a great skillset to learn.

[754]

If I didnt have 3 lathes, and keep paying for a place to use them.. even when I am not making money..

 I would probably have cooler bikes that actually run...

 Hey , I know people that have lathes, that cant be bothered, to learn how to use them...

[Ricky_Racer]

 You can probably run without it, Kawasaki does, and Morris wheels as well.. but it would look funny on there..

754... Can you elaborate? I've got a rear Morris and rear Cambray wheel I want to use, neither of which seem to be threaded for a screw-in retainer ring. First time I've seen this design.  Are they safe?  What's the skinny?  Do the bearings mount from the opposite side?  Thanks!  RR

[754]

Look at the Morris sideplate, does the bearing appear to be inserted from outside, ie, you see the whole outer bearing race, nothing holding it in?

 On a flat track hub, the bearings are just pushed in the ends.
 The bearings should be held from side movement as there is spacers on both sides of the inner bearing race on both bearings, so they should not move from their location. Some locktings are also a sealholder, but that is not needed on a double sealed bearing,,, single seal facing to outside would do the job..

[Ricky_Racer]

Thanks, 754. I'll check tomorrow and try to upload closeup photos of both brands of wheels for everyone's use. I'll clean the edges of the bearings to see if there appears to be a retaining shoulder in the hub.  Thanks again.  L8R.  RR

[fastbroshi]

Dagersh,

  I just realized you posted pics and a more concise explanation, thank you.   I finally got my rear wheel retainer out last night after setting it on top of some rubber mat on the garage floor and going to work.  I heated the outside of the hub with a mini torch and proceeded to beat the retainer with a hammer and punch.
  I found out it was much easier to keep the hub from spinning around on the floor than on my bench.  It also reminded me about another one of those little peripheral tips when it comes to using tools.  When you're hitting something with a hammer, you can tell the the quality of blow you've laid just by the sound that comes from the object your hitting.  Hit a punch off center or while not making good contact with the object to be struck, and the sound gets a little tinny.  Hit it solid and it rings much differently.  Keeping this in mind, four or five good solid raps with the ball peen and a bullet-nosed punch got it spinning out.
 

[bharvey60]

Had a local machine shop make a large tap for the internal threads. Cost was $50 and it worked like charm on heavily damaged threads. Took 15 minutes to make and 2 minutes to restore threads.


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I am here:

[Ibdsharpe]

Hello   What a great idea. Your lucky to have a convenient and reasonably priced machine shop. Would you consider renting it out to members? I have a brand new pair of metric thread chasers I purchased recently before I realized they were for external threads only..............guess I didn't read fine print. I've already purchased another hub but the original with the bad threads is completely polished and has new bearings so I don't want to discard it for sure. Let me know if rental is acceptable to you.

 Thanks    Dave Sharpe

PS: my rear hub is for CB750K5