Originally Posted by
DannoXYZ
Chain tension is determined by length and in this photo, the derailleur cage is rotated all the way back and not under much tension:
The red pulley should actually be at a 45-degree angle (closer to the ground) relative to the other one. If you're not in the granny-ring up front, then you need to remove 2-4 links from the chain as it's too long and slack.
Sorry, typo on my part. It's most likely the derailleur hanger-bracket that's bent. But typically all the parts between the pulley-cage to hanger gets bent. Start with this photo:
Rotate the pulley-cage so that it's vertical, then pull outward to bend back into proper position. The two pulleys should be inline vertically, the lower one is currently bent inwards.
Originally Posted by
Homebrew01
The rim is probably a bit bent. You need to have even spoke tension to keep the rim straight. If a spoke is too loose or too tight due to damage or just bad tension, then the rim will either be pulled towards or away from the bad spoke(s).
If the axle bearings are loose, that can also cause wobbling, but spoke problems are the most common cause.
Originally Posted by
DannoXYZ
This may be due to loose rear-wheel bearings. They may just need to be adjusted.
However, your spokes are severely undertensioned. I can see at least one that has zero tension. The wheel may have previously been damaged into a taco shape and was trued back to look straight with vastly varying tensions. I suggest having a shop adjust the bearings (or learn to do it yourself). Then tighten up all the spokes evenly. If you squeeze two parallel spokes with your hand as hard as you can, they shouldn't bend together any more than 4-5mm. I suspect yours will move 10-20mm.
Here's a good site showing how to adjust hub-bearings: Park Tool - Hub Overhaul & Adjustment
Originally Posted by
DannoXYZ
How do you define "proper"? There's enough holy-war debates on chain oil here to realize that there's no one "right" lubricant. One of my requirements is longevity of drivetrain and I can get 7000-10000 miles out of a chain before 1/16" stretch.
Yeah, that reminds me there was a time (I was a kid then mind you - this bike is ~9 years old) when the front and rear wheels needed to be trued. I went to a backstreet cycle shop, and the guy did it for free. I was later aware of the fact that the moron who "fixed" my bike re-welded the wheel until it was straight. He didn't tru it >:/
Originally Posted by
DannoXYZ
Chain tension is determined by length and in this photo, the derailleur cage is rotated all the way back and not under much tension:
The red pulley should actually be at a 45-degree angle (closer to the ground) relative to the other one. If you're not in the granny-ring up front, then you need to remove 2-4 links from the chain as it's too long and slack.
Sorry, typo on my part. It's most likely the derailleur hanger-bracket that's bent. But typically all the parts between the pulley-cage to hanger gets bent. Start with this photo:
Rotate the pulley-cage so that it's vertical, then pull outward to bend back into proper position. The two pulleys should be inline vertically, the lower one is currently bent inwards.
Originally Posted by
Homebrew01
The rim is probably a bit bent. You need to have even spoke tension to keep the rim straight. If a spoke is too loose or too tight due to damage or just bad tension, then the rim will either be pulled towards or away from the bad spoke(s).
If the axle bearings are loose, that can also cause wobbling, but spoke problems are the most common cause.
Originally Posted by
DannoXYZ
This may be due to loose rear-wheel bearings. They may just need to be adjusted.
However, your spokes are severely undertensioned. I can see at least one that has zero tension. The wheel may have previously been damaged into a taco shape and was trued back to look straight with vastly varying tensions. I suggest having a shop adjust the bearings (or learn to do it yourself). Then tighten up all the spokes evenly. If you squeeze two parallel spokes with your hand as hard as you can, they shouldn't bend together any more than 4-5mm. I suspect yours will move 10-20mm.
Here's a good site showing how to adjust hub-bearings: Park Tool - Hub Overhaul & Adjustment
Originally Posted by
DannoXYZ
How do you define "proper"? There's enough holy-war debates on chain oil here to realize that there's no one "right" lubricant. One of my requirements is longevity of drivetrain and I can get 7000-10000 miles out of a chain before 1/16" stretch.
Just got back from Halfords (automotive/bike/camping shop which also deals with repairs) and on the way I realised that it was probably one of the bearings. Oh, and I forgot to mention that the rear mech is completely FUBAR - it's cracked and broken in a few places which is why it isn't a quick fix
Total cost of parts + labour of fixing the bike (incl. rear mech, bearings etc) comes to roughly £50.
Originally Posted by
DannoXYZ
Chain tension is determined by length and in this photo, the derailleur cage is rotated all the way back and not under much tension:
The red pulley should actually be at a 45-degree angle (closer to the ground) relative to the other one. If you're not in the granny-ring up front, then you need to remove 2-4 links from the chain as it's too long and slack.
Sorry, typo on my part. It's most likely the derailleur hanger-bracket that's bent. But typically all the parts between the pulley-cage to hanger gets bent. Start with this photo:
Rotate the pulley-cage so that it's vertical, then pull outward to bend back into proper position. The two pulleys should be inline vertically, the lower one is currently bent inwards.
Originally Posted by
Homebrew01
The rim is probably a bit bent. You need to have even spoke tension to keep the rim straight. If a spoke is too loose or too tight due to damage or just bad tension, then the rim will either be pulled towards or away from the bad spoke(s).
If the axle bearings are loose, that can also cause wobbling, but spoke problems are the most common cause.
Originally Posted by
DannoXYZ
This may be due to loose rear-wheel bearings. They may just need to be adjusted.
However, your spokes are severely undertensioned. I can see at least one that has zero tension. The wheel may have previously been damaged into a taco shape and was trued back to look straight with vastly varying tensions. I suggest having a shop adjust the bearings (or learn to do it yourself). Then tighten up all the spokes evenly. If you squeeze two parallel spokes with your hand as hard as you can, they shouldn't bend together any more than 4-5mm. I suspect yours will move 10-20mm.
Here's a good site showing how to adjust hub-bearings: Park Tool - Hub Overhaul & Adjustment
Originally Posted by
DannoXYZ
How do you define "proper"? There's enough holy-war debates on chain oil here to realize that there's no one "right" lubricant. One of my requirements is longevity of drivetrain and I can get 7000-10000 miles out of a chain before 1/16" stretch.
See above.
The oil I used is chain lube.
Cheers
