SA 3sp: Auto changing 1<->2 gear
09-02-10, 11:25 AM
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SA 3sp: Auto changing 1<->2 gear
When im in first gear on my SA 3sp (1950's) it randomly switches back and forth between 1st and 2nd gear. I know that can be caused by a worn ring but are there any other causes? It started rather suddenly.
09-02-10, 01:18 PM
#2
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Too much cable tension, such that 1st is just at the edge of second? But this doesn't make sense, since it would require some release of cable.
I suppose if the frame were flexing a little in such a way as to make a little slack in the cable. But how?
Wait. Do I have it right? Taut cable, low gear; slack cable, hi gear, right?
OK. Some combination of cable tension and frame flex. That's my (possible) answer.
I suppose if the frame were flexing a little in such a way as to make a little slack in the cable. But how?
Wait. Do I have it right? Taut cable, low gear; slack cable, hi gear, right?
OK. Some combination of cable tension and frame flex. That's my (possible) answer.
09-02-10, 01:45 PM
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From the Sturmey documentation:
Self changing between 1st and 2nd Gear 1. Worn gear ring pawls 1. Replace
Self changing between 1st and 2nd Gear 1. Worn gear ring pawls 1. Replace
09-02-10, 03:05 PM
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09-02-10, 03:21 PM
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Could be a worn/weak shifter spring too.
Aaron
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Webshots is bailing out, if you find any of my posts with corrupt picture files and want to see them corrected please let me know. :(
ISO: A late 1980's Giant Iguana MTB frameset (or complete bike) 23" Red with yellow graphics.
"Cycling should be a way of life, not a hobby.
RIDE, YOU FOOL, RIDE!"_Nicodemus
"Steel: nearly a thousand years of metallurgical development
Aluminum: barely a hundred
Which one would you rather have under your butt at 30mph?"_krazygluon
09-02-10, 06:23 PM
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