WheelyTheGreat

Hello vintage friends,
I‘m currently trying to replace a 7-speed Shimano 105 HG/UG freehub body on my Motobecane Jubilee Sport (1982), but the new NOS Freehub simply won‘t fit on the rear hub, although the inner spline pattern looks the same. I can‘t post pictures at the moment, since I’m a new member, but here is some info: both freehubs have the same dimensions and look almost the same. On the bottom side the new FH has some additional rubber rings which are missing on the oder one. BUT, the hub socket looks the same.

Does anybody know what I‘m missing here? Are there some different hub socket standards one should know about?

Cheers,
Wheely

oneclick 

Check that your freehub spline isn't missing the single wide spline that HG cassettes have.

https://www.sheldonbrown.com/k7.html

bboy314

What exactly is the issue you’re having? Splines don’t line up? Freehub binds when tightened?

WheelyTheGreat

Sorry for misunderstanding, I didn’t mean the splines on the freehub, but the splines (maybe it‘s the wrong word for it, they look to me more like teeth of a cog) in the hub itself, where the freehub is inserted. There are 12 equidistant teeth on the hub

WheelyTheGreat

The old freehub slides gently on the hub body, the new one doesn’t move a millimeter, as if something is misaligned. Both look „almost“ the same to me ( I promise to post some pictures, when I’m allowed )
So at the moment my question is, if there were different, but similar standards for connection of the freehub with the hub

Reynolds 

I think there were different spline patterns, but they would be very different and evident by eye.

top506

Post pictures to your gallery. The Mods can then post them here.

Top

WheelyTheGreat

Thanks I have just uploaded the pics to the galler. The new FH is on the left.

machinist42

"Body Transplantation.
Most Shimano Freehub bodies are interchangeable. The exceptions are:

• Very early Freehubs (sometimes identifiable by the absence of the typical bulge on the right end of the hub barrel) which have non-interchangeable bodies. The Freehub body of these hubs is held on only by the axle bearings, and will slip off once the axle is removed.
• Hubs that use the "silent clutch" mechanism.
• Pre-1997 Dura-Ace Freehubs, which only take pre-1997 Dura-Ace bodies.
• FH-7800 and FH-7801 Dura-Ace bodies, which have a cartridge bearing inside the Freehub body and use a ratchet inside the hub shell. These bodies are removable using a 5 mm Allen wrench at each side. The fixing nut on the right side unscrews clockwise. Shimano information on the 7800; 7801.
• FH-7850 and FH-7900 Dura-Ace bodies, which have returned to a splined attachment between Freehub body and hub shell, but it is larger than the usual one. It is similar but not interchangeable between these two models. Shimano information on the 7850; 7900...."https://www.sheldonbrown.com/k7.html

OP's Album.

icemilkcoffee 

pic assist




Does the freehub spin freely before you put it on? Also- some of these freehubs need a spacer shim. Otherwise it will tighten against the hub and it can't spin. Where did you get this freehub from? Did it have a spacer shim?

Also- what is wrong with the old freehub?

bboy314

Did the old one have a thin spacer between it and the hub shell? This may be needed with the new one. But you might just have one that’s not exactly compatible with that hub. It can be hard to determine cross compatibility with these. I recently did an 8 speed swap for a RSX hub, used a freehub made for Tiagra 4500.

mbrraleigh

The freehub doesn't spin at all? You may need a washer at the hub/freehub interface but that may not be a guarantee it will work although the replacement freehub certainly looks close. Many Shimano hubs were designed to use a dedicated washer but some were not. I just serviced a deore LX freehub on a FH-M580 hub. That hub used a small circular washer. You might look at an exploded diagram if you don't know what I'm refering to.

KCT1986

It looks like the hub is one of the really old ones, early 80s. Possibly one of the ones that used that just used the cone & bearings to hold the freehub body onto the hub shell.

Your 'old' freehub body seems to already be a replacement. It is HG style, so probably not original. Your 'old' freehub body may have a washer on it, (based on the pic).

If the washer is there, transfer it before fitting the 'new' body.

Not sure what all that black 'stuff' is on the hub shell. Is it just cake on grease? Or is there a plastic or rubber spacer on there? It and the lack of the washer may be restricting the freehub body from spinning.

Clean off what you can and post a pic, so we can see what's there.

dddd

Those freehub bodies aren't made for that hub at all, they are supposed to be secured using a hollow bolt that the axle passes through.

I don't know why one even fits on there, possibly it was modified!

I would find a complete 7s freehub (or complete wheel) for this repair.

Even among HG freehubs, many do not interchange parts-wise with others, the cassette won't be at the right distance from the spokes and the cone, spacers, seals and such also won't fit properly.

When I have swapped freehub bodies, it's either the identical part or a similar one complete with all of the axle hardware to go with it. I have had difficulty swapping random freehub bodies for the above reasons, even though the splines were identical. Adding/subtracting the washer never fixed a problem with a mis-fitting freehub body.

Your particular style of (internal/external threaded) 7s freehub body is special in that a 10s cassette can be mounted on it with the right (11t-size, long-threaded) lock ring nesting into the recess of a 12t smallest cog.

Jeff Wills

This. The hub shell has a tubular support that pressed into the cassette body instead of a hollow bolt that screws into the hub shell. This is typical of mid-‘80’s Uniglide hubs. Since the cassette body has already been replaced and it has expired your best bet may be to unlace the wheel and lace in a new (er) hub.

Sorry to be a downer but… it’s toast.

wrk101

I always find replacement freehubs in the form of a wheel. Pick up a used wheel at a co-op, or even pick up a complete bike. Depending on condition, you might swap entire wheel(s) which avoids any compatibility issues.

Whenever I scrap a a set of wheels, I save cassettes, freewheels, free hubs and entire hubs. Just scrapped a set this morning.

WheelyTheGreat

This old freehub is a tiny little bit loose, regardless how strong you tighten the freehub’s inner cone. I read somewhere that it might be because the the inner washer is missing (I checked, and it wasn’t there). As a result, when assembled, the cassette „wobbles“ a little while pedaling.

The new freehub body spins all right (with my finger as an axis). I bought it online as a NOS Shimano 105 part.

The old freehub was assembled by a friend of mine, who says there wasn’t a spacer shim between the freehub body and the freehub. Neither was there spacer delivered with the new one.

WheelyTheGreat

As far as I know, there is now washer required. Even if it was needed, this would have nothing to do with my problem: the seemingly identical freehub doesn‘t fit on the rear hub‘s interface

WheelyTheGreat

That all black stuff is just some grease. Otherwise, you are right: only the cover and bearings are holding the rear hub. But there is definitely no washer required between the FH and the flanges.

WheelyTheGreat

I guess you’re right. I‘m just kind of eager to learn about this old stuff and standards and I‘m ready to invest some time for that. I‘m currently making the bike ready for a bike trip I‘m having in a couple of weeks and want to get the old beast to roll as smooth as it gets

masi61

I'm curious to see a picture of your hub. It is hard to tell from your description if the freehub body is held on with a bolt or if it is one of the older ones where the bolt is imbedded in the FH body itself. I like 7 speed Uniglide stuff, it is very well made and generally durable and re-buildable but as others have said, it is important to stick with the exact model for replacement. I put a UG/HG freehub onto a 7 speed uniglide only hub and it did fit but there was some slight incompatibility with the rubber seals making riding it in the rain not quite as water tight as it should have been.

KCT1986

If your original post is correct, the link is for the spec sheet. This seems to be the only 105 that used that freehub attachment style.

SI-M-98-000-00-ENG.pdf (shimano.com)

The original freehub body was 'press-fit' onto the hub shell.

As mentioned previously, the freehub body that you removed was not original. It was a HG style with one narrow spline out the outside for cassette alignment, a HG feature.

The body that you removed may not have been designed for a press-fit and just slid on the shell. Did you have to use the tool to pull it off? See how the original body was removed per the linked doc. If the tool was not needed, then the balls/cone was the only thing holding the freehub body against the hub shell.

If the body that you are now trying to install is going part way onto the shell and meeting resistance, it may need to be pressed on per the instructions. Per the instructions, this is done by using the 2 washer included with the removal tool. The washers go between the cone on the axle and the bearing cup without the ball bearings installed. The cones are tightened to push the freehub body onto the hub shell. The force used was not very high, see the torque spec, (relatively low). The cones/axle is then removed and ball bearings installed.

Of course, this was with the original freehub body designed for the hub. With the freehub body that you have, this may not work.

WheelyTheGreat

I‘ll upload some pictures of the hub later this week. Now I have assembled everything back and will try to make the best out of the weather

WheelyTheGreat

Wow, this definitely gives me some insights. To your question: no, I didn’t have to use any tool to remove the freehub body from the hub. So I guess you‘re right about the originality of the freehub.

And big Thanks for the link!

WheelyTheGreat

I finally found some time to take a picture of the rear hub. Is anyone familiar withe exact type of it?