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Discussion Starter · #1 ·
I am looking for replacement cogs for my DA 7 speed free hub. Is there any ready source of new replacements parts for a group this old? I would prefer new as this is a bike that I actually ride. New would last longer that used. Of course, lightly wore used is the next best option.

The bike in question is circa 1990 (or there about). My frequently used cogs are starting to wear out; new chain skips under heavy load.

Thank you in advance for your help.
 

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Stogaguy said:
I am looking for replacement cogs for my DA 7 speed free hub. Is there any ready source of new replacements parts for a group this old? I would prefer new as this is a bike that I actually ride. New would last longer that used. Of course, lightly wore used is the next best option.

The bike in question is circa 1990 (or there about). My frequently used cogs are starting to wear out; new chain skips under heavy load.

Thank you in advance for your help.

Are you talking about the Uniglide cogs??

If so a new DA 7 speed cassette is damned near impossible to find cheap.... I have tried. There is one on eBay for 90 fricken dollars!?!?!

The issue is the final cog.... the threading is different on the DA hub than all the other uniglide hubs. So, threaded cogs for DA Uniglide hubs are not cheap or easy to come by.

However, I have 43 Uniglide cogs that will be here this week that I got from a guy that converted to HG. I am only going to need about 10 of them so if you need some of the following let me know...however, I will not have any extra threaded DA cogs.

These are all Uniglide cogs. The first number is the tooth count and the second is how many of each.... I'll post a pic if you are interested in when they arrive.

>12x1 (non DA screw on)
> 13x6 (with built in spacer)
> 14x4
> 15x5
> 15x1 (with built in spacer)
> 15x1 (DA)
> 16x4
> 17x2
> 17x1
> 18x3
> 19x4
> 20x1
> 20x1 (DA)
> 21x3
> 22x1 (DA)
> 23x1
> 24x1 (DA)
> 26x1
 

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I forgot about another auction I am watching that may have some more bits... including some threaded cogs.

What are you looking for specifically and maybe we can split the booty :)
 

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Dave Hickey said:
Try loosescrews.com.. That had a bunch of uniglide DA cogs

Loosescrews did not have any 7 or 8 speed DA threaded cogs, nor did it have any DA 7 or 8 speed cassettes. Do you know if the 6 speed ones work if you add another cog or a spacer?
 

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Discussion Starter · #7 ·
Pardon my ignorance

I do not know if my bike is Uniglide or Hyperglide. Perhaps you can tell me.

There are no model numbers on the freehub that I can see. I would post pics but do not have a digital camera at my disposal. So a description will have to do.

My bike has 7 speed indexed down tube shifters. My derailleur is marked RD 7401, with 6S-7S SIS marked on the cage. My parts were purchased as a group so I believe that would make my freehub a 7401 as well. I believe this to be the Shimano’s first 7 speed freehub. The cogs are individual as opposed to being fixed together into a cassette.

The largest five cogs slide onto the splines of the freehub body with separate spacers in between the second position cog (second to the smallest) has a built in spacer, which I beleive is a proprietary Shimano design. The first position cog (smallest) is threaded onto the freehub body and holds all the other cogs in place. All of the cogs have the teeth twisted so the leading edge of the tooth is further outboard than the following edge. The cogs for the five largest positions are marked with the number of teeth follow by the word index, e.g “21 index”. The second position cogs are marked in the following format “14 index 7-8S”. The threaded (first position) cogs are marked “7S LC” or “7-8S NE”.

Based on this description, what do I have? What cogs are compatible with my system? Must they be Shimano or are there other brands that will do as well? The cogs that I need to replace are all of the “flat” (largest five positions type).
 

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You can also use Hyperglide cogs, if you file down the wider spline. All splines on Uniglide freehub bodies are the same size, while Hyperglide has one spline that's wider, to ensure that the ramps on the cogs all line up the same way. That won't help you with your last cog, which is threaded on Uniglide cassettes. Hyperglide uses a separate lockring.

The cheapest option would be to replace the freehub body with a 7 speed STX-RC hyperglide one.

http://sheldonbrown.com/harris/k7.html#bodies

Then you would be able to buy 7 speed hyperglide cassettes, which will likely be available forever, or nearly so.

You could also put on a 8/9/10 speed body, but you'd have to respace the hub and redish the wheel.

--Shannon
 

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Discussion Starter · #10 · (Edited)
Strategy / Follow-up question

Thank you everyone for your informative responses. After reading your advice and Sheldon Brown’s articles on this subject, I decided on the following strategy:

  1. Flip the cogs: According to Sheldon, worn Uniglide cogs (for the largest 5 positions) can be flipped over (installed “backwards”) and will run just “like new”. This is a quick, easy, and cheep fix. However, given the twist in the teeth, this just sounds a bit goofy. Does anyone have experience doing this? If so, how did it work? Provided this actually works, this is the route that I will go in the short term.
  2. Convert to Hyperdrive: Long term, I will convert the hub to Hyperglide by changing the freehub body. This solves the parts availability problem long term. If properly executed, this will also create a level of interoperability with any future road bike that I purchase. I will admit that I do not like the idea of putting “non-period” components on what is arguably now a retro-classic. However, my primary goal is to ride the thing, not treat it like a museum piece.
 

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Stogaguy said:
Thank you everyone for your informative responses. After reading your advice and Sheldon Brown’s articles on this subject, I decided on the following strategy:

  1. Flip the cogs: According to Sheldon, worn Uniglide cogs (for the largest 5 positions) can be flipped over (installed “backwards”) and will run just “like new”. This is a quick, easy, and cheep fix. However, given the twist in the teeth, this just sounds a bit goofy. Does anyone have experience doing this? If so, how did it work? Provided this actually works, this is the route that I will go in the short term.
  2. Convert to Hyperdrive: Long term, I will convert the hub to Hyperglide by changing the freehub body. This solves the parts availability problem long term. If properly executed, this will also create a level of interoperability with any future road bike that I purchase. I will admit that I do not like the idea of putting “non-period” components on what is arguably now a retro-classic. However, my primary goal is to ride the thing, not treat it like a museum piece.
First, let me know how the flip around thing works. If it doesn't work well send me a note for the cogs sizes you may be interested in and I will sell them to you for cheap. I am not looking to make any money, just recoop some costs of a batch of more than I really needed.

Second, I thought that converting to HG would be a good cost effective idea, but the catch is you need a pre-1997 Dura Ace HG Hub Body and a special Shimano tool made specifically for removing the hub body, both of which are difficult to come by and are likely as expensive as just getting a new hub. The post-1997 Dura Ace hub bodies are fastened by a bolt that won't work on "our" older hubs.

By the way, if anyone is interested in a 7400 series 8 speed Dura Ace hub set PM me. The rear is a Uniglide with a 130mm drop out. I got these on eBay before I realized what a pain they would be to find cassettes for. I am going to keep my 7 speed hub with a 126mm dropout since it was already built into a wheel, but the 8 speed hubset is for sale. I am hoping to be able to offer a working cassette made from my batch of cogs as well. We'll see after they come in.
 

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Discussion Starter · #12 ·
Testing the "flip thing"

handsomerob, to test the “flip thing”, I just flipped all of my five largest cogs. While it sounds counterintuitive, this does not change the orientation of the twist on the teeth as I feared. As a result, I see no reason why this procedure will not work. I will repost if I encounter any problems on my ride today.

Thank you for your offer to share your wealth of Uniglide cogs cheap. I appreciate it. However, I remain committed to the Hyperglide conversion strategy. I agree that there will be some costs associated with the conversion. However, the most important issue for me is interoperability going forward. The Shimano tool required for freehub removal on pre 1997 DA hubs, TL-FH10, seems to be readily available from Harris Cyclery and others. Harris seems to have compatible Hyperglide freewheel bodies available as well.
 

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Part of my question to Sheldon Brown

"Anyway, I believe that I need two Dura Ace freehub bodies in order to convert them, which also requires borrowing the special tool to take the hub apart. First question is do you have any more of these compatible freehub bodies for sale, if so how much are they, and lastly can I still borrow the tool to complete the job"

From Sheldon Brown himself about a month ago when I was having these same issues.... (who responded to my email to him in 10 minutes!!!)

"The info on the Website is correct. However, there are a couple of reasons why you shouldn't do this...

The Freehub body costs more than a complete modern _hub_. You would get better value for your money with a new Ultegra or 105 hub.

This modification only makes sense if the old Dura-Ace hub is already built up into a very nice wheel and you want to save the whole wheel. If it's just a loose, hub, it's a losing proposition.

Also, to do the swap, the hub needs to be built up into a wheel first, otherwise there's no way to hold the hub shell without damaging it while you unscrew the old Freehub body, which will be very snug indeed."

Also, I was not able to find any of the FW7403 hub bodies for sale.... how much are they?
 

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Discussion Starter · #14 ·
freehub body FW8808

Looks like the freehub body required is FW8808 currently listed at $69.95. Here is a link.

http://sheldonbrown.com/harris/k7.html#bodies

My hub is currently built into a wheel so there is no problem there. I see Sheldon’s point about just going with a new hub. However, I would like to save the DA hub so as to not break up the set. The biggest bummer for me seems to be that I will have to change my shifters and probably my rear derailleur. Thankfully, the “flip thing” gives me time to ponder my options…
 

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Stogaguy said:
The biggest bummer for me seems to be that I will have to change my shifters and probably my rear derailleur. Thankfully, the “flip thing” gives me time to ponder my options…
Why would you need to change either? You can put 7 speed cassettes on 8/9/10 speed freehub bodies, and as long as you've got 6/7/8 speed DA shifters, your 7-speed DA derailleur will index.

--Shannon
 

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Discussion Starter · #16 ·
May convert to 10 speed

Shannon, you are completely correct if I stay with 7 speed. However, I will eventually get another bike, most likely 10 speed. In the past, when I have owned more than one road bike, I have preferred to keep all of my wheels compatible with all of my bikes. Therefore, I am tempted to go the full 9 yards and convert to 10 speed. However, shifters could prove to be the fly in the ointment. Does anyone know if they make10 speed indexed down tube shifters?

On a separate but related note, flipping my worn Uniglide cogs worked like a charm. My drive train is quieter, shifts better and the skipping under heavy load is gone. I put about 10K miles on these cogs before flipping them so I am good for a while now. I am sure that I will wear out my “non-flipable” first and second position cogs before I wear out the one I just flipped.
 

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Discussion Starter · #18 ·
Conversion summary

Dave Hickey said:
An 8 speed cassette will index just fine with the existing parts too. The spacing between cogs is almost indentical between 7 and 8. 7 speed index shifters will "click" and extra position for the 8th cog...I've done this many times...and it works great.
Thanks Dave, that is good to know. So if I understand it correctly in order for me to Hyperglide I would need to do the following. Please note there are some questions in here.

7 Speed:
  1. Change to a Hyperglide freehub body: FW8946 (for 7 speed, 126 mm spacing) or FW8808 (for 8/9/10, 130 mm spacing, would require a spacer inboard of the cassette for 7 speed)
  2. Change to 7 speed Hyperglide cassette.
  3. All other drive train components remain the same.

8 Speed:
  1. Change to a Hyperglide freehub body FW8808 (for 8/9/10, 130 mm spacing)
  2. Change to 8 speed Hyperglide cassette.
  3. All other drive train components remain the same.

9 Speed:
  1. Change to a Hyperglide freehub body FW8808 (for 8/9/10, 130 mm spacing)
  2. Change to 9 speed Hyperglide cassette.
  3. Change to 9 speed chain
  4. Change to 9 speed shifters (down tube to utilize existing braze-ons, what is the part number?)
  5. Change to 1997 or later Shimano derailleur
  6. All other drive train components remain the same. (Is a 9 speed chain compatible with my DA7400 chainrings?)

10 Speed:
  1. Change to a Hyperglide freehub body FW8808 (for 8/9/10, 130 mm spacing)
  2. Change to 10 speed Hyperglide cassette.
  3. Change to 10 speed chain
  4. Change to 10 speed shifters (SL-7800)
  5. Change to 1997 or later Shimano derailleur
  6. All other drive train components remain the same. (Is a 10 speed chain compatible with my DA7400 chainrings?)
 
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