Shifter Slipping Out of Lowest Gears
03-27-21, 05:22 PM
#1
Newbie
Thread Starter
Shifter Slipping Out of Lowest Gears
Hello folks,
During my ride today, I discovered my bike is having some shifting issues. It's an 80s Novara Randonee, with Suntour Symmetric downtube friction shifters. I'm not sure if Symmetric is the actual model name, but that's what it said on the housing. They're the ones that mount on top of the downtube and are supposed to automatically trim the FD when you shift the back. Anyway, the issue is that on the smallest chainring (28t), whenever I'm in a gear lower than the highest or second highest in the back, the shifter doesn't seem to have enough resistance to hold the derailleur there, and it will slip until the chain rests on the second smallest sprocket. This happens even when pedaling easy, not just under load. Anyone know what the issue could be? For reference, the rear derailleur is a medium cage Dura Ace with large jockey wheels and the cassette is a 7 speed 23-13. I bought this bike recently and this was only my second ride on it, so I haven't changed cables or adjusted derailleurs yet, though the previous owner knew his stuff with bikes and seemed to have treated it well. Thanks for any help.
During my ride today, I discovered my bike is having some shifting issues. It's an 80s Novara Randonee, with Suntour Symmetric downtube friction shifters. I'm not sure if Symmetric is the actual model name, but that's what it said on the housing. They're the ones that mount on top of the downtube and are supposed to automatically trim the FD when you shift the back. Anyway, the issue is that on the smallest chainring (28t), whenever I'm in a gear lower than the highest or second highest in the back, the shifter doesn't seem to have enough resistance to hold the derailleur there, and it will slip until the chain rests on the second smallest sprocket. This happens even when pedaling easy, not just under load. Anyone know what the issue could be? For reference, the rear derailleur is a medium cage Dura Ace with large jockey wheels and the cassette is a 7 speed 23-13. I bought this bike recently and this was only my second ride on it, so I haven't changed cables or adjusted derailleurs yet, though the previous owner knew his stuff with bikes and seemed to have treated it well. Thanks for any help.
03-27-21, 05:25 PM
#2
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Hello folks,
During my ride today, I discovered my bike is having some shifting issues. It's an 80s Novara Randonee, with Suntour Symmetric downtube friction shifters. I'm not sure if Symmetric is the actual model name, but that's what it said on the housing. They're the ones that mount on top of the downtube and are supposed to automatically trim the FD when you shift the back. Anyway, the issue is that on the smallest chainring (28t), whenever I'm in a gear lower than the highest or second highest in the back, the shifter doesn't seem to have enough resistance to hold the derailleur there, and it will slip until the chain rests on the second smallest sprocket. This happens even when pedaling easy, not just under load. Anyone know what the issue could be? For reference, the rear derailleur is a medium cage Dura Ace with large jockey wheels and the cassette is a 7 speed 23-13. I bought this bike recently and this was only my second ride on it, so I haven't changed cables or adjusted derailleurs yet, though the previous owner knew his stuff with bikes and seemed to have treated it well. Thanks for any help.
During my ride today, I discovered my bike is having some shifting issues. It's an 80s Novara Randonee, with Suntour Symmetric downtube friction shifters. I'm not sure if Symmetric is the actual model name, but that's what it said on the housing. They're the ones that mount on top of the downtube and are supposed to automatically trim the FD when you shift the back. Anyway, the issue is that on the smallest chainring (28t), whenever I'm in a gear lower than the highest or second highest in the back, the shifter doesn't seem to have enough resistance to hold the derailleur there, and it will slip until the chain rests on the second smallest sprocket. This happens even when pedaling easy, not just under load. Anyone know what the issue could be? For reference, the rear derailleur is a medium cage Dura Ace with large jockey wheels and the cassette is a 7 speed 23-13. I bought this bike recently and this was only my second ride on it, so I haven't changed cables or adjusted derailleurs yet, though the previous owner knew his stuff with bikes and seemed to have treated it well. Thanks for any help.
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Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
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03-27-21, 06:20 PM
#3
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The "Symmetric" shfter doesn't have a D-ring for tension adjustment, but it does have an Allen bolt that serves the same purpose. Part #9 in the diagram:
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03-27-21, 06:37 PM
#4
Newbie
Thread Starter
I tightened up the Allen bolt and gave it a spin on the trainer. That seems to have done the trick. Thanks.
03-27-21, 08:45 PM
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FWIW... friction shifters depend on enough friction to keep them in place. Too much and they are difficult to move. Too little and they don’t stay in place.
John
John
