ThermionicScott 

My guess it's to limit the number of different cogs they need to make. I have a similar "gripe" about the spacing of Shimano's 13-15-17-19-21-24-28 "M" cassette (I would much prefer 13-15-17-19-22-25-28) and 13-15-17-20-24-29-34 "K" cassette (13-15-18-21-25-29-34 would be better.) I put "gripe" in quotes because it doesn't seem to be as much of a problem when I'm on the road.

Some of the cheap new 5-speed 14-28 freewheels go 14-17-21-24-28 which looks fine until you graph it.

John E

If you are a dim bulb, I am equally dim -- that 19-24 jump comes right in the sweet spot of high-use gears, and it reminds me of the stupid 70s standard Schwinn Paramount 14-16-18-23-26 freewheel, which is my own favorite six-speed 14-16-18-20-23-26 with a gaping hole right in the middle of the progression.

pastorbobnlnh 

Actually, most are notched or come with splines.

When considering only the major vintage players in the '60s-'70s, Regina, Atom, Maillard, Suntour and Shimano, yes the first two used threaded and they are interchangeable. Maillard used a combination of threaded and notched. Suntour was all over the place with both threaded and notched, and Shimano mostly used splines, but also had notched and threaded cogs.

I've been thinking this through: With the correct kind of press and die cutter, modern SRAM, Shimano, Sunrace, etc., cassette cogs could have the center cut to form compatible freewheel cogs. The same press with different die cutting tools could be employed to make cogs for existing Suntour, Shimano, some Regina, and Sachs freewheel bodies. This might be the ultimate solution, especially for those elusive 23T, 25T, and 26T cogs.

crank_addict

IMHO, I wouldn't freak about it.

Different story though on race car chassis. All purpose built race cars have limited longevity and for intended use. Then there's the expected crash including how quickly and easy can they be repaired. Even way back and in the case of Chapman, the master of 'cutting' weight, by running coolant water thru the chassis tubes I don't think he cared about corrosion or concerns for the racecraft's many years later survival. As for the tubes change in properties during fabrication, some way back then may or may not have cared. Build them and get them out the out the door to teams. Debateable, but probably one of the reasons Lotus gambled with lightweight but sacrificed dependability.

--- back on topic: My LBS owner mentioned his collection of FW and cogsets is going for decorative art applications in his house. LOL.

Lenton58 

Well ... you have a point that I could have expected to be raised — and you do know your race cars!

As for the topic: in your opinion should I bend my Simplon-Romani — originally 120 — to 130 and then bend the DO's back parallel on the alignment bells. Then I can go bonkers in the free-hub playground and forget the bloodletting hunt for vintage stuff.I welcome more of your opinion. Maybe all of us should just get on with it and bend the stays out. We'll not all of us. Who is going to do that to a late 50's Cellini or a 1938 Bates!?

(BTW — as an aside, my friend found that Chapman's welders were not the most skilled — and showed me the evidence. I was rather shocked! But then it was not a team F-1 machine ... maybe an an F2 and reduced to Formula Junior.)

John E

... and replace the chain when it has elongated by 0.5% (1/16" per 24 half-links, per Sheldon Brown's recommendation).

jimmuller 

If I recall correctly, Colin Chapman was once quoted as saying on the ideal race car everything should break just as it crossed the finish line. Don't think I would have wanted to race for him! Of course, practicality always gets in the way.

But to justify this post by getting back to freewheels, my Motobecane has a conventional 5-speed, 14-28 paired to a somewhat custom compact double crank, 47-34. Most of my other bikes have 6-speeds with compact double cranks. The most radical (for me) is the Masi's 14-34 6-speed with a 47-42 half-step crank. The riding styles are different, but I can live them just fine, thank you. For example, yesterday morning I took the Moto out for 24 quick (at least for me) miles, 16mph, 1550ft of climbing. I used the full gear range, but spent most of the time on the big-24, big-20, and big-17 combinations. Would another cog have made much difference? Probably not. Most of the time I was running at my aerobic limit. When I needed a higher or lower gear I had one available.

At least the bike didn't break, it simply braked, as I reach home.

gaucho777 

I share Pastor Bob's sentiment that it is well worth overhauling an old freewheel. There are lots of lightly used freewheels that can be salvaged and given new life. It really is not as challenging as Sheldon makes it sound. I do keep my eyes out for those elusive 24t-26t Regina cogs. I'm not overly worried about freewheel supply though, as I have been gathering spare freewheels (have added a few more since this photo was taken).

jyl

I have spent some more time persuing eBay for 7 speed FWs and my conclusion is I should HTFU and learn to push a 13-21 over any hill, since that flavor of vintage FW is still fairly accessible. Failing that, my alternatives are (1) move to Florida, (2) triplize my bikes, (3) buy a dozen Sunrace 13-25 FWs while they are cheap. Or, (4) insinuate myself into gaucho777's last will and testament.

bikemore 

Sachs FW come up on ebay from time to time. Often they are of the 13-19 or 13-21 variety, but you still see 13-28 or 13-26 go for reasonable prices. They spin fairly quietly, but I have to admit to favoring the Dura Ace ones so I haven't actually run one.

Darth Lefty 

I'm thinking it wouldn't be prohibitive to make threaded FW cogs out of freehub cogs, at least at ultra 6/7 spacing which is par with 8 speed. Making splined ones would be worse in small batches (machining the splined hole more difficult than threading) and better in large ones (stamping splined hole easier than threading)

gaucho777 

I'm glad this thread came up when it did. It prompted me to search and find another back-up 26t Regina cog.

rootboy 

OK.
She has 7 more of these. She says. Helluva deal for a very scarce size in a very good freewheel. Keep an eye on her auctions.
Regina 5 Speed Free Wheel Italian Thread Road Racing | eBay

This public service message is brought to you by an unabashed Regina fan who is related to the seller no way, no how.

gaucho777 

Make that 6 more.

Dave Mayer

Nope. I have 2 bike Co-ops within a few blocks. At any one time, they have bins that are overflowing with 100 pounds of decent old freewheels. And there is our local recycling depot, which 'compresses' 150 old bikes per week. And then there is Ebay, scavenging and creativity.

Creativity: for example, you can replace most of the cogs on 6/7 speed Dura-Ace and Shimano 600 freewheels with cogs from their current inexpensive offerings. This takes some hammering and a little grinding. The transplanted Hyperglide cogs shift better than the old Uniglide ones.

Or if you have an old Sachs freewheel, by grinding off one of the 4 tabs, you can double the life of most of the cogs by flipping them. No apparent deterioration in shifting.

And keep in mind that 90% of the bikes sold to this date still use freewheels. Freewheels will likely be around forever.

jyl

Now you're just rubbing it in.

jyl

I forgot what enablers you guys are.

Since starting this thread I have bought two Sunrace 13-25 online, a Winner, a Winner Pro, and a Sachs (8 speed!), so my freewheel hoard now looks like this plus a few more in the bin and the in-transit Sunraci.



Two of these are just "weigh-in" freewheels, being aluminum and installed just to weigh the bike. One is a wide range monstrosity that I decline to ride until another decade passes. The rest are 12-17, 13-19, and 13-21 "HTFU" freewheels. And there may be one "reasonable freewheel" for a not over strong, 50 plus guy. Maybe.

I am hoping at some point to take them apart and figure out how I might be able to get a couple more reasonable freewheels from the mess.

Cassave

It's actually easier than that. Both laser and abrasive waterjet cutting could be used to profile a freehub cog bore to an old freewheel configuration. The only tooling needed would be a holding fixture that centers the cog and properly "clocks" it for it's position. No distortions induced by stamping or fine blanking and equal tolerance control.

No hard tooling required, only an IGES file or similar.

pastorbobnlnh 

Probably with @ftwelder 's help, a centering and holding jig could be made. Let me look into a shop that does this sort of cutting.

Thanks for the great idea.

JohnDThompson 

Zeus was ahead of the game in this area: all the cogs were splined, with the same spline pattern, except the final cog, which was threaded and held the rest in place. No spacers were needed, as the cogs were machined to provide the intended clearance. And the bodies could be removed from the hubs using either the then-ubiquitous Regina 2-prong remover, or the superior splined remover later adopted by Regina, Everest, Atom, etc.

old's'cool

Amen brother!

Amen brother.

gaucho777 

As long as this silly trend continues, there will be a bountiful supply of unwanted freewheels.

gaucho777 

Pastor Bob: If you build it, the cog orders will come.

pastorbobnlnh 

This really does give me something to think about.

For a few years now I had wished there was a way to mate a modified freehub outer body to a freewheel inner body in order to use cassette cogs on a freewheel. Of course this could never be done because of the smaller size of the freehub. Why I never thought about adapting cassette cogs to fit a freewheel body until now? Well--- I guess I needed this thread (insert "Smack Yourself In The Head" emoticon here)!

If @jonwvara can find a machine shop to manufacture new 122BCD and 144BCD triplizer chainrings, why can't I find a means to modify cassette cogs? I'll probably start with the spline pattern that fits Shimano and Sunrace bodies. I'm guessing this will also work on the other modern freewheel bodies but will need to verify this at some point. It would seem that 25T and 26T are the most requested, so I'll need to find a source for those cassette cogs.

I think I have found my retirement business. Don't any of you C&Vers go stealing my idea!

SJX426 

I just started searching for IRD freewheels and was having difficulty finding them. I am concerned they will be discontinued. What is avaialable may be NOS. IRD still has a reference to their freewheels but don't id the tooth count.

@pastorbobnlnh This is a crazy idea but I was wondering if an EDM tool could be made to modify cogs. First step would be to mill out the min ID needed and then EDM the spline configuration. Shouldn't take too long depending on how many cogs you do at once. Registering to the center line of the cogs could be a challenge or not. Just create a fixture with indexed holes for alignment pins for tooth count (cog sizes)The tool could be easy to make but a bit expensive if copper. It been about 20 years since my exposure to this process and I don't know if it is improved or not. I created a tool for placing splines in an AL block machined for a Yamaha Vision handle bar mount. Worked out well! Should take a picture of the tool the next time I run into it.

Other alternative methods might be water jet or lazer. The material is thin enough that it might actually work with enough precision. Been too long and don't really know how viable these from a precision perspective.