rosefarts

Before I mess it up.

Got the Uniglide cassette off no worries. Scrubbed the years of nicotine off the body, spokes, and rims. Now it's time to grease the bearings.

The assembly looks the same as most hubs except for some dimpled plastic caps that say "open" and "close".

What is that? A seal? Does it need to be turned to open before I grab the spanners? They're 35 years old and Uniglide, so if I break them, they're gone.

Speaking of Uniglide. Am I correct that according to Sheldon, I cannot do a HG freehub on this? The way I read it was that you can swap 6, 7, and 8 UG bodies but cannot put a HG on for Dura Ace.

So if I want to expand my 13-24 6 speed cluster, I need a Dremel tool, a 7 speed cassette that comes apart, and to guard my 13 tooth threaded cog with my life. This is a pretty cheap and viable option actually if it works.

Dan Burkhart 

In the open position, there is a small hole to admit a grease needle. moving to the closed position seals it off.

HillRider

According to the VeloBase web site there were 8-speed Uniglide/Hyperglide freehub bodies made for the 7400-series Dura Ace hubs as the FH-7403 model. Unfortunately, you are limited to freehub bodies specifically made for the 7400-series hubs as their mounting system is completely different from later 7700 Dura Ace, 105, Ultegra, etc. models.

Here is the VeloBase web page:

VeloBase.com - Component: Shimano FH-7403 / HB-7400, Dura-Ace 7400 (Hyperglide Rear)

speedevil 

I can say with certainty that the 7403 freehub will handle a 10 speed cassette. I had a set of very nice 7400 hubs with a 7401 freehub. Since 7403 freehubs are basically unobtanium, I was lucky enough to pick up a set of donor hubs with a 7403 freehub. To swap the freehubs you will need the special tool, I don't see any way to remove the freehub without it, except for destructive removal. Not recommended. I had to lace the 7403 hub into a wheel to produce enough torque to remove the freehub.

You may have to swap in a longer axle to have the 7403 work with a 10 speed cassette in a frame with 130mm rear dropout spacing. Even if your axle is the proper length for 130mm spacing, the tool to tighten/remove the cassette lockring will not fit over the cone locknut. You just have to tighten the cassette lockring before inserting the axle.

Also, the cone/locknut on the drive side will be recessed into the 7403 freehub, so you'll have to tighten them before inserting the axle and make your preload adjustments on the NDS. Not a big problem, you just have to alter your normal sequence.

rosefarts

Compatible within the 740x line and nothing else?

So I've got the bike together and rideable. It's actually pretty sweet as it sits. I'm going to leave the gearing as andi just not take this into the mountains.

I would like to get the UG freehub body off for lube. It's a 35 year old bike that has sat for 30. I'm absolutely certain that the freehub only has the lube it came with when new. Other than a specific tool that I probably can't get, can it be done? Can I inject light grease into it? Not the axle bearing (cleaned and lubed those already) but the freehub?

speedevil 

I don't think there is realistically any way to remove the freehub without the tool.

I can ship mine to you so that you can use it, as long as you ship it back when you're done. PM if you're interested.

rosefarts

I'll talk to my lbs tomorrow, if they can't do it, we'll make a plan.

speedevil 

OK. Before installing it into the hub, I lubed my 7403 by soaking it for a couple of days in a bath of Mobil 1 Synthetic gear oil. Then took it out and let it drain for another couple of days. That should take care of it for a very long time.

Interestingly, the Shimano docs for the 7400 hubs say that the threads on the freehub and the threads in the hub should be dry, no oil or grease on either. Seems odd to me not to use something when dissimilar metals are threaded together but I followed their instructions.

dedhed

https://www.bikeforums.net/bicycle-m...y-remover.html

https://si.shimano.com/pdfs/si/SI-N-...00-ENG_GER.pdf

Read this thread
https://www.bikeforums.net/classic-v...n-minutes.html

DaccordiDolan

The other thread is perfect - has sent me looking for 'square key steel' and I found a hardened steel tool quality lathe key - have used a bench grinder and ground it slight flatter at end to flatten end chamfer and it has just removed freehub when in a metal vice - perfect!
Lathe Chuck Key Imperial and Metric Variation Square Head Engineering Variation...7/16
see ebay
£8.49!

noglider 

I'm glad this thread was revived, as it is timely for me. I just built a wheel with a 7403 hub. Someone led me to believe I could put a 10-speed cassette on. I succeeded, but it was tricky. The last cog stuck out a lot, and it was hard to put the lock ring on. I jiggled a lot to make sure everything was compressed, and eventually, it went on.

Are there lock rings with deeper threads that can make me feel safer? I know it's probably safe enough.

I know I'll need some weird-azz tool to remove the freehub. A friend of mine might have one already.

icemilkcoffee 

Are you trying to put a 11t small cog on the 7403 freehub? The 11t small cog does not work with freehubs with full length splines. It only works with freehubs with splines that stop short of the end:

noglider 

It's not an 11-tooth. I know that for sure. I'm pretty sure it's a 12-tooth. And I'm not trying; I succeeded, so it's definitely not an 11-tooth. My freehub looks different from the two you pictured here. It has threads on the end, intended, I believe, for the old style cassette. I understand this was a transition-period hub meant for both styles.

icemilkcoffee 

Do the splines measure ~35mm long? If so it should take a 10 speed cassette. In fact 10 speed cassettes typically require a 1mm spacer behind the cassette because it is too narrow to fill that 35mm (10 speeed cassettes have the dished in backside)

KCT1986

The standard freehub body for the FH-7403 is a HG/UG body with both internal and external treads. Don't recall ever seeing a HG body that is different than that style that would attach to the 7400 series.

Because of the unique attachment system of the 7400 freehub system, only the 3 body styles designed for the series would attach (HG/UG; 7; or 8 speed UG with the smaller threaded outer sprocket).

As for the question about a longer treaded lockring, some of the 12 speed Shimano road lockrings are a little longer. Possibly because of the way that the outermost sprocket of the 12 speed interfaces with the 'next' sprocket. Also, some other brands of cassette lockrings comes with longer threads, especially aluminum lockrings.

Dave Mayer

I pulled one of my spare 7403 freehubs out and measured: 35mm. It only accepts cassettes with 12 and larger first position cogs.

noglider 

Thank you, everyone! I will measure the splines. I think I'll see how this lock ring holds up and won't seek a new one. I'll just make sure it's good and tight.

KCT1986

If the lockring is steel & serrated, and engages a couple of tread, it should be fine. Most of the force in the sprockets are rotational and supported by the splines.

About removing the freehub body, only necessary if maintenance is needed. Very hard to find a replacement that will work on the 74?? series, and only 1 style 'natively' takes a HG cassette (the one that you seem to already have).

noglider 

Super. Thanks again!