Hydra-Glide neck bearings and fitting tin

Post Reply

Hydra-Glide neck bearings and fitting tin


Post by h2o » Sun Aug 20, 2006 7:54 pm

Post by h2o on Jun 9, 2006, 10:22am

Howdy folks from a new member. ;D

My problem is my I'm doing a resto on a '54 BT and the fork panels are about 1/8" shy of matching up with the mounting holes on the triple trees. I saw an earlier post about these darn neck bearings being a problem for the earlier rigids if everything including the stars and moon aren't in perfect alignment, so I must be falling into that category, ???
The neck cups and bearings I'm assuming are the correct '49-'59 type. When I removed the races that were in these cups they were Timken 07196, thus they matched Palmer's measurements exactly. I purchased 2 new Timken 16 roller bearing sets (07100/07196) and installed them into the neck cups.

I've also double checked the neck dimensions without the races installed and the neck spacing should be good according to the 49 frame blueprint I'm looking at (5.645").
The upper tree has 56120-48 casting # and the lower tree has 457##-48 (can't see the 2 ##'s right now but they are the OEM #'s (I checked when they were visible).
I've got 4 front panels, all early 4 bar type (2 oem, 2 repro), and they are all pretty darn close for bolt hole alignment, so no of them fit.
I believe the upper head bearing seat (upper dust cover with nut, OEM # 48330-4 I'm using is the correct OEM part, but I cannot find a good picture to verify that. ???
If anyone can provide me with some measurements related to the neck bearings, etc. on preferably a '49-'57 hard tail frame, or at least a pre-60 frame, I just might figure this thing out. :-*

At present, what I find on my set up are the following measurements:

1) The frame neck without cups installed i have dressed to 5.645 (my '49 blueprint shows 5.648 REF, 5.642.)

2) Lip of Bearing Cup to Lip of Bearing Cup without bearings = 6.968

3) Lip of the lower cup to the shoulder of the bearing installed in the upper cup (lower tree removed with top bearing in place and no dust cover) = 7.070

4) Lip of the lower cup to the exposed shoulder surface on the dust cover (where the top tree would rest once installed) = 7.210

The top dust cover (bearing seat) has an inside boss which adds another 0.1785 in height to this setup (measured from where it shoulders to the bearing [lower shoulder] to where it shoulders to the bottom side of the upper tree [upper shoulder]). Above the upper shoulder there is a guide for the top tree that is about 0.15", though irrelevant since it sits inside the upper tree at the stem hole.

Somewhere in all this I need to shrink this measurement by about 1/8" or 0.12" minimum to get the fork panels to fit.

I'll add 1 more bit of info on this. When I got this frame the neck had been cut up for a chopper and the sidecar loops cut off. The frame is originally a mid-54 as it is a wishbone with no evidence of horn blocks or flattened tubes, and had the late motor mount. A fellow I met wound up giving me the front section that is now on it (I had it professionally re-spliced by some frame fellows with the jig). The wishbone the fellow gave me he kind of recalled that it was from a knuckle but really couldn't remember for sure. The front section has no horn blocks or flattened tubes, and has a steering lock and the pin in place for the steering damper washer. Per Palmer, that would narrow the front section down to only a late '48 or mid '54. I believe in '48 they were still running ball bearings but had been fit with this style neck in anticipation of the hydra glide. Now I've reasoned that the neck should be the same, whether for '48, '49, or '54 as it has the correct casting marks (per Palmer), and it seems logical. I'm assuming that the dimensions will be the same, only the cups should have changed.

Hopefully someone can help me make some sense of this before I act a fool and break out my grinder and goggles! :

I'm expecting perhaps the cups needing to be cut some inside for the races to drop some or cutting em down on the outside shoulder so they can sit down in the frame a bit, or something is funky about the top or bottom tree, but I figure some measurements and perhaps someone having had this problem may make this process much easier - Any thoughts will be appreciated. h2oh

Post by panacea on Jun 9, 2006, 12:31pm

My wishbone neck measures 5.66 with a caliper, I dont have any cups yet.MW

Post by sleeper on Jun 9, 2006, 4:16pm

Welcome h2o-

Knucks never used the *wishbone frame*.....
It made it's first debut for the 1st yr Pan, '48
Make sure the fork-panels are not for a evo Fat-Boy or Heritage, etc,...
as they are different in hole locations (slightly)

Post by VPHD on Jun 9, 2006, 5:22pm

I think the 49-59 cups once installed in the frame have a lower profile than later cups, which causes this problem. Vintage Twin had a couple of posts about this problem a while back.

Post by panacea on Jun 15, 2006, 11:00pm

H2O, did you ever figure out what the correct cups should be for a wishbone head? I've got what I think are the wrong ones and dont want to open up the package till I'm sure. Thanks! MW

Post by h2o on Jun 15, 2006, 11:44pm

Whew!! I may have figured this out, but won't know for sure untill I get another lower tree in hand. In summary, I found that my 49-59 neck cups were not much different than a '60 up OEM neck cup with regards to the bearing height (only about 0.010 difference). The things that added up the most dimensionally were running an aftermarket neck cup set with the 2-piece dust cover set-up. The lowest profiles (measuring from where the neck cup seats up to the frame, to the dust cover's shoulder on the nut where the upper tree seats to it) came from the 49-59 and '60 up OEM neck cups with a 1 piece OEM race seat (upper dust cover). I found about a 0.060 difference between the OEM set and an aftermarket set.

This still didn't get me what I needed as I was looking for about 0.125". Turns out, I believe, my problem is in the lower tree. The one I have has the correct OEM number cast below the bearing area. A parts vender asked me if my fork stops were notched, and they are. I have looked at pictures that was provided by another fellow of an early lower tree versus what I have, and see some differences. These being: 1) The part number is cast to 1 side of the stem on the early versus centered below the stem on mine, 2) the fork stops are rounded on the early tree versus being distinctly notched on mine, and 3) in the cast area above where the cow bell screws are, mine has the shoulder machine faced versus the early one which is rounded (un-faced). Similarities are: 1) At first glance, everything looks about the same, 2) They both have the same part number, and 3) They both have a hole drilled in the stem for a neck lock. I believe that the bearing must drop down a tad bit more relative to the fork panel mounting threads on the early style.

I think if someone is going to have problems getting their tin to fit, the most likely scenario will be due to running aftermarkets with the 2 piece upper dust cover setup. Next, check the lower tree for notched fork stops. Then, make sure the bearings are not mixed, as early bearing in later cups, though they seem to run well, will increase the height another 0.060 or so. Conversely, early bearings in the later race will lower the setup about 0.060 or so. Finally, check that the neck shoulders are square with the cups, there isn't excess paint where things match up, and that all other mating surfaces are squared up (no big dings, etc.)

I have taken so many measurements, tried this and that, etc., I could just about write a book on it. If you have problems, I'll be happy to share the info I have. h2o

Post by panacea on Jun 16, 2006, 12:46am

H2O, thanks for the insight, before I could tell my machinist about the different 49-59 type bearings and cups he had already gotten me a 60 up set.
strangely enough the bearings I had in there were the 19 roller LL44643, not the 16 roller. So it should be fine. The cups he got me say 49-94 48311-60 . Keepin' my fingers crossed,LOL MW

Post by h2o on Jun 16, 2006, 1:52am

I'd say the only time it is a problem is when the parts don't fit, or if you're after bone stock original. I see an error in my message in what I said and what I meant to say were 2 diffierent things, if anyone cares. I meant to say that putting later 19 roller bearings (L44643's) in early races (07196) will increase the height, putting the early bearing (07100)into a later race will drop the height.


'49-59 Forks Cups


Post by VT » Thu Dec 07, 2006 4:14 am

Yep, the 1/8" mis-alignment is due to no '49-59 cups are available yet, except from Mark Blankenship. He makes them and cads them. The '60 up cups are taller. Makes the tins not line up. Get some cups from Mark. V-Twins making them in Taiwan someday. JW got that going with Tedd last year. If somebody needs cups let me know and I'll post Mark's phone number. You can tell if yours are '60-up the bearings of the Timkens have 19 rollers. '49-59 bearings have 16 rollers.
He made mine and they worked nice. Froze the races, they dropped in with little effort using a bench press and an old race fipped over as a a driver.

Post Reply

Return to “Frame & Fittings”