WARNING....USE OF REPLACEABLE UNIVERSAL JOINT

[Rio Wil]

I have taken on the project of rebuilding a ujoint using the Universal 392 joint and doing the measurments and machining to make the joint fit.

I might be wrong about this, but if anyone has one of these joints in use, I think it is not made properly and is a danger.

Rational:  The 392 I bought under the Precision Universal label has bearing cups that are .002 smaller than the original joint.....meaning they are not a press fit into the ears and are being retained only by the c-clips.  This means the cups are free to wallow around in the ears and will quickly enlarge the ear bores and will FAIL.........

If I am wrong about this feel free to enlighten me immediately......

The following is an excerpt from a thread I have started to document my experience in retrofitting a stock joint with the Universal Precision 392 joint. 

 
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Well.....appears the joke is really on me.....I just measured the cup diameters of the Precision Universal 392 ujoint and they are .002 smaller than than the original.  Needless to say, that is about the amount of the press fit so these cups just slide right through.

So, now back to the research, I thought the research had been done and the 392 joint was a fit but with the loose cups, it simply will not work,

I am sure I did not ream the ears oversize because the old cups are still a nice tight press fit....

So I have to ask the question....has anyone any knowledge of a 392 joint being actually installed and did the cups fit with a proper press fit.

The joint I bought comes in a box labeled Precision Universal, the joint is actually made by GMB in Japan.....this statement is simply a point of reference.

I found the below dimensions while searching for info and they are very misleading and not to be relied on either.........so crap......

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outside to outside of c-clips is 1.62" three days from purchase to my front door $20.00 each free shipping!  cooldude
cap dia. 0.79 ,  overall cap to cap outside 2.337"=

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SO IF ANYONE IS USING ONE OF THE REBUILT UNIVERSALS WITH OUT THE CUPS BEING PRESS FIT AND ONLY RETAINED BY THE CCLIPS.......REMOVE IT IMMEDIATELY OR YOU WILL DIE!!!!!!!!!!

Also take a look at the picture of the 392 compared to the original.....it ain't as beefy!!!!!!!

[Chrisj CMA]

I think I remember reading that a Honda CR-V U-Joint is a suitable replacement.  I googled it and found that there is one part for earlier than 2000 and another for 2000 and later.  I would hope the later one is the right one, it looks improved over the older one. 

Hope that helps your research

[Rio Wil]

WELL-WELL-WELL........I think I am beginning to understand.

It appears the original ujoint bearing cups are what is known as "drawn cup needle bearings", these cups have a thin wall sheet metal housing.  They are designed for high loads and are of good quality.

The dimension of the bearing is oversize for the bore it is to live in and is intentionally shrunk upon installation to fit.  The bore it fits into is dimensionally the same as a ground cup bearing (in our case .788) with a shrink fit of .790........thus a .002 interference fit.  A standard ground cup bearing will essentially pass right through the ear bore of .788 because it is .788 also....thus no interference fit.  I suspect this is the reason the rebuilder in Redding had such a hard time finding "good" yokes, ground bearing cups simply passed through with no interference. 

So the challenge then is to find a ujoint of proper dimensions with drawn cup needle bearings and they will fit our yokes just fine.....will have a nice interference fit and life is good.

So the question is, where do we get such a joint.........buy it from the same vendor Honda does if that can be identified, or buy a ujoint from Honda, remove the joint and bearings and install in our good yoke......or....ya ready......just use the part from Honda and be done with it......

So....it looks like I am done with this project unless we can identify a source of the proper ujoint with bearings .....

AND to think I cratered a reasonably good ujoint to find this out.....crap

Chris mentions below that Honda CRV might have the identical ujoint...might be worth checking out.

I will post this in the other thread and unless the CRV thing pans out......I'm done....

[pancho]

I ran into some info from back during the ujoint shortage 2010 2011,,, before my time,,,  it seems that some tack welded the caps in place.   there are a few pages

http://www.valkyrieforum.com/bbs/index.php/topic,21521.10/wap2.html

I wonder how that worked out in the long run,, it doesn't really seem like a good idea to me .

Here, check out the top two entries.....

http://rockforddriveline.com/ujointinside.htm

[Rio Wil]

I can't imagine the tack job lasting very long....if the fit was so loose as to require a weld, it is too loose!

[3W-lonerider]

i am a testament to the 392 u-joint not holding up. last winter i paid a guy to reman the yokes to fit a 392 joint.
when i received the joint it was as advertised. .. installed it and made sure i greased that joint every 3000 miles.
  i have a trike and the u-joint is open so i remove the driveshaft every 8000 miles to grease the output splines on the tranny.
 i'm thinking i only have 12,000 miles on that joint.
 the last 2 times iv'e ridden iv'e gotten a real bad vibration when letting off the throttle.
tonight i went out and removed the driveshaft. sure enough 1 cup on that joint had no bearings in it at all.
heres what i found. the cups were allowed to move out in the yokes far enough so that the seals on the cups allowed water to get in and ruin the bearings.
i think if i would've taken 1 more ride, that u-joint would've blew apart and my drive shaft woulda dug into the road creating a possible catastrophy.
the u-joint at the rear end of the shaft has 100,000 miles on it and is still holding up quite well.

[art]

You can try and have the bores chrome plated to the correct size for a press or shrink fit.It is done all the time rebuilding jet engines. It usually is a hard spray and machined after.Just a thought