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Sachs 7 speed freewheel

Old 11-29-23, 08:52 AM
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Sachs 7 speed freewheel

I’m curious about this old Sachs 7 speed freewheel. At first glance I assumed the teeth were damaged, but then I checked the same NOS freewheel on ebay and it would appear that these teeth being machined this way was an intentional design. I would assume that they thought it would help with shifting. Anyone know the history behind these? The first image is from the bike I just purchased, the second image (not installed) is from ebay.


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Old 11-29-23, 08:56 AM
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Sachs Maillard Freewheel
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Old 11-29-23, 10:21 AM
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There was a tiny elf at the Sachs/Sedis factory with a grinder. He loved to scar the cog teeth. The Sacks folk saw that it didn't do any harm, finding that elf was going to be hard and punishing him would not be popular if word got out. So they just made it quite clear - you can grind the teeth but only so much and do it uniformly.

And completely off topic - I see you have both the fender and rack running to your one dropout eye. I've been doing the same forever, but - I always place the rack strut next to the dropout and the fender strut(s) outside. I learned long ago that a heavy load on the rack and any slippage at all at the bolt and the bolt bent or broke. With the strut next to the dropout, the bolt is loaded in pure shear where it is the strongest and the nut has a far easier time of staying tight. (Yes, modern bikes like yours have better dropout quality, etc. than many of my bikes back then, but still ... And I still always bolt up my fenders outside any rack.)
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Old 11-29-23, 11:09 AM
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This freewheel looks perfectly normal - factory spec teeth. It's been about 10 years since I rode this type of Sachs freewheel, but I remember it shifting well, on par with Hyperglide, and better than Uniglide.

Unfortunately the cogs tend to wear quickly, as the steel seems to be softer than the super-hard material in Dura-Ace freewheel cogs. I've flipped these Sachs cogs when they got worn, with little apparent effect on shift quality. Of course this only applies to the non-threaded (bigger) cogs. Grinding of one of the 4 inside cog splines is required to make this fit.
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Old 11-29-23, 11:13 AM
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Originally Posted by 79pmooney
There was a tiny elf at the Sachs/Sedis factory with a grinder. He loved to scar the cog teeth. The Sacks folk saw that it didn't do any harm, finding that elf was going to be hard and punishing him would not be popular if word got out. So they just made it quite clear - you can grind the teeth but only so much and do it uniformly.

And completely off topic - I see you have both the fender and rack running to your one dropout eye. I've been doing the same forever, but - I always place the rack strut next to the dropout and the fender strut(s) outside. I learned long ago that a heavy load on the rack and any slippage at all at the bolt and the bolt bent or broke. With the strut next to the dropout, the bolt is loaded in pure shear where it is the strongest and the nut has a far easier time of staying tight. (Yes, modern bikes like yours have better dropout quality, etc. than many of my bikes back then, but still ... And I still always bolt up my fenders outside any rack.)
Good catch! I just bought the bike yesterday, 1983 Specialized Expedition. I would never mount a rack like that either and will take mental note about it when tearing it down and rebuilding properly.

Quite the innovative elf from back in the day! 😁
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Old 11-30-23, 01:56 PM
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...this is from the grand era of steel bike weight weenies. They probably did it to save weight.
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Old 12-04-23, 10:55 AM
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As the notches are on the trailing edge of all the teeth, you can presume they were cut deliberately cut to aid shifting. A-B tests against freewheels by SunTour and SunRace would tell us if they are effective.
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