Bike Forums - View Single Post - Chain keeps falling off brand new Kona Rove (Shimano Sora)
Old 05-24-20, 09:05 PM
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Andrew R Stewart 
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I suspect there may be a few different things going on. The big ring chain drop is often an adjustment issue. Ft der twist, height and outward limit. But the shift to the small ring can sometimes be technique. Why would a shift lever release to the small ring act any different after a few times? Because the rider is also changing their pedal pressures. The classic is an attempt to shift down to the small ring with no result (but grinding) because the chain is too taught, too much pedal pressure. Rider moves lever back to large ring to stop grinding and tries again. But now their cadence is slowing and to keep momentum they push harder on the pedals (after all the reason to down shift is usually because of a hill or headwind). Attempt two does no better with the slower cadence (and that the shift gate takes longer to align with the even more tensioned chain). At some point of repeating this the rider, whether knowingly or not. shifts when the chain is relaxed enough to allow the der's return spring to overcome the chain tension, and the chain gets moved over enough to cause a shift.

Of course other issues contribute to these things. Like a well worn chain that now has a lot of lateral flex. Or a messed up shifter that won't release or move up as it should. Then there's the cable routing thing about the anchor bolt and it's tab's guide stub. Any thought about this? Andy
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