Got in a fast 30 miles today - first ride of the season for the gold Colnago Mexico. I was about a mile from home when I accelerated hard out of a bend on the Sammamish River Trail and my chain began to grind, then hop along madly. I shifted over a few cogs and everything was okay. Hmmm...

When I got home and took a good look, this is what I found:



I was pretty sure I'd broken the cog - but not 100% because although I've done it three times before, those other times were all alloy cogs - this bad boy is all steel. @pastorbobnlnh I need a rescue (this thing is almost NOS, be a shame not to just replace the cog and put it right back to use).

I'll admit it felt kinda cool to know my body is still capable of breaking things

DD

Gotta get that leg torque under control DD.

Im glad it was the rear derailleur that snapped.

He! Nice work! We have broken sprockets on the tandem, but tben there are two of us.

Nice work!

Took it off, cleaned it up and took a couple more pics:





DD

What brand of freewheel is that?


Edit: oops, never mind. We were both posting at the same time.

Geez is that all? When I clicked on this post I expected to see a cracked drive side dropout or something....

CX freewheel is it? They did fail on occasion. The Regina Oro was much more reliable IME. I had a few CX's and never had a failure myself, but I remember a couple of them coming into the LBS in broken condition BITD.

Alloy freewheels were a different story. Good for like 3 rides... I remember one dude shearing all the teeth off of a cog on one of those Zeus things..

Nicely done!

Magnus Bäckstedt would be proud of you, you can now be called Drillium Dude, destroyer of freewheels

Put on an old stretched chain. it will all be good.

Remind me never to get in a city limit sprint with you.

Hydrogen embrittlement maybe? Did you by chance soak the FW in a solvent for cleaning? I know it is newish, but a lot of us clean NOS components to get rid of the old grease in them and replace with new.....

I mostly run Oros and Extras. I will look, but I'm fairly certain there's one more CX - or maybe a BX. Were BXs suspect, too?

The alloy ones I broke were on a Regina (alloy America, in the same way this broke) and I did in two Everest Novas by splitting the collars at the threaded portion in two separate incidents. I was standing up for the second one...

Swore off alloy after that.

DD

But still! I hate when this happens - it's always a huge surprise. I almost went off the trail as a result

DD

You'd have to ask Pastor Bob. He did an overhaul on this unit last year. I know his basic technique, but not the specifics regarding solvents and the like.

I wonder what it was about the cog metal that was different from the Oros and Extras that came before (and apparently had little/no issues)?

There's every chance I can get a new cog in there and be good as new, but I am going to have to put this on a bike I use for easy days. Trouble is, sometimes easy days (like today was supposed to be!) have a way of turning into hammer-time rides

DD

Jeff is totes gonna kick our ass up Hurricane Ridge this summer. Just sayin'

Time to start training.

DD! You monster! You Hard Man! I think there is still time to get you in the peloton for the TdF!

If I'm not mistaken this is your Regina CX freewheel pictured on the bottom of my home page (https://www.freewheelspa.com/).

With the additional pictures, I see that it is a 14T A1 or three splined sprocket. It will be interesting to see where the split occurs. There's a good chance I can replace it. Unfortunately (for you-not me), I'm on my annual post Easter break and far away from the snow, salt and sand of NH's spring roads, so the Spa is on shore leave.

I won't be back until after April 29th, but you can send it my way and the local PO will keep it under lock and key until I return.

All the sprockets were cleaned the same, IIRC, in a water-based-ultrasonic metal approved cleaning solution. Because they were NOS, I might have just cleaned them with hot soapy Dawn dish detergent. My guess is there was a weak spot between the splines. Only a metallurgist with a microscope would be able to tell us for certain.

Too cool, totally worth it.

This is the sort of thing for which pics or it didn't happen was created.

Get thee to the velodrome.
That sort of torque needs to be tapped!
Brent

Honestly I don't know what the story is on the BX freewheels. Oros and CX were sold in LBS's as aftermarket components. It went straight from oro to CX, with no BX in between. I definitely remember this. CX were the cool new thing, and they were oddly quiet.

Perhaps the BX was on OEM only item. Or maybe they were introduced in the late 80s as a lower priced freewheel? Not sure. I was going to college then and not paying much attention to bike stuff. Anyone know?

In my neck of the woods, alloy freewheels were considered special race only, kind of like 28h wheels.

Beast mode ---- engaged

Yes.... [MENTION=168558]Drillium Dude[/MENTION] - but did you “break” a sweat?!


Sorry, I can’t help myself....

Come on Bob, don't be a Myth buster...