Crank gear won't shift down
07-16-09, 05:37 AM
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Crank gear won't shift down
I'm having some problems with my crank gear. When I'm trying to shift down the wire just gets loose and the front derailleur doesn't move. If I push it hard with my foot it usually shifts down. Shifting up works fine, but it feels like there's much resistance. What should I do?
07-16-09, 08:12 AM
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I can't see how tightening the cable would help. When shifting down the tension in the cable is released so the derailleur can move freely down to the position below and is then stopped by the cable, now with tension. Isn't that right? My theory is that the spring that forces the derailleur down is stuck in some way, but I have absolutely no idea on how to fix it.
07-16-09, 08:54 AM
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Bicycle Repair Man !!!
Clean and lube the derailer...also check that your cables are moving freely through the housings.
After that, check the limiter screw on the derailer.
After that, check the limiter screw on the derailer.
07-16-09, 10:54 AM
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How old is the derailleur?
Is it under warranty?
Has it been damaged?
Try lubrication.
Check the cable routing under the bottom bracket.
You may need a new one.
Al
Is it under warranty?
Has it been damaged?
Try lubrication.
Check the cable routing under the bottom bracket.
You may need a new one.
Al
07-16-09, 04:29 PM
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It's getting quite a few years old now and it has defiantly no warranty anymore 
I've been trying to lubricate it without much luck. It seems like I can't to the problem area with the lubrication. Maybe it should take all the pieces apart to clean it properly. It seems hard though, if not impossible. Getting a new one might be good advice...
I've been trying to lubricate it without much luck. It seems like I can't to the problem area with the lubrication. Maybe it should take all the pieces apart to clean it properly. It seems hard though, if not impossible. Getting a new one might be good advice...
07-17-09, 05:12 AM
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If it were me, I'd orient the bike so I can drip kerosene or sometimes Liquid Wrench on the derailleur (even "bombing" it from above) then, if you can get the nozzle relatively close, blow the liquid farther into the part with air from a compressor.
07-17-09, 10:36 AM
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Yeah, this sounds to me like a road crud or corrosion issue. Fill the sucker with a light oil and exercise it manually to break up the gunk and get the oil into the moving parts.
