Derailleur Pulley Tension

Anna

Well-Known Member
Region
USA
Disappointed that I have not been able to sort this out… I recently had a bad flat (rear tire). After making the repair I tried reinstalling my wheel and chain. The pulley mechanism stays horizontal. I have tried manipulating the chain… 😕. I did shift to the highest ⚙️ gear before removing the wheel. Perhaps a photo will clarify the problem… Thank you friends in advance. 🚴‍♀️
2A319E31-AC19-445D-88E6-B0A38453A380.jpeg
 
With the bike upside down on handlebars & seat, you crank the pedals and shift the shifter until the chain moves to the largest sprocket. If the takeup moves til it is almost fully retracted, you are fine. If the chain won't move, it is likely trapped between the smallest sprocket and the frame. Has to be moved with a screwdriver onto the smallest sprocket.
I usually change the tire with the chain somewhere in the middle sprocket. Then when I put the axle back in the chain loop, sometimes I have to wind up the spring on the takeup with a pair of chanl-lock pliers as my hands are not very strong. Compared to most men, I mean. Keeps my hands clean by not handling the oily chain. If I need to move the chain while the wheel & sprocket are in the air, I lift it with a flat blade screwdriver. Or hook it with the open end of the 15 mm wrench.
If you can't turn the bike upside down because of the display, you bought the wrong bike. I can't help you. I installed my display so it could be swung down after loosening screws for chain & tire maintenance. Some people have been known to spend $$$ to buy "bike stands" that hold the bike with the wheels in the air seat up. How those people change a tube out on the road is not explained to me. I roll the bike over, sometimes leaning it against a tree or a cable TV generator box or something. As I can't lift all of my 94 lb bike at once, a stand would help me not at all. I'd need a crane to lift the bike onto the stand. Maybe I should have been born with bigger arms, but then I'd be rock wall climbing or lifting weights or swimming or something instead of riding a bike.
I have to say I learned bike maintenance by doing it, not by watching videos on U-tube. Nor was there anybody to watch. Bike club members laugh at me as they blast by at 3 times my speed, or run stop signs all around me. I see them standing around sometimes waiting for the sag wagon to do the maintenance.
 
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With the bike upside down on handlebars & seat, you crank the pedals and shift the shifter until the chain moves to the largest sprocket. If the takeup moves til it is almost fully retracted, you are fine. If the chain won't move, it is likely trapped between the smallest sprocket and the frame. Has to be moved with a screwdriver onto the smallest sprocket.
I usually change the tire with the chain somewhere in the middle sprocket. Then when I put the axle back in the chain loop, sometimes I have to wind up the spring on the takeup with a pair of chanl-lock pliers as my hands are not very strong. Compared to most men, I mean. Keeps my hands clean by not handling the oily chain. If I need to move the chain while the wheel & sprocket are in the air, I lift it with a flat blade screwdriver. Or hook it with the open end of the 15 mm wrench.
If you can't turn the bike upside down because of the display, you bought the wrong bike. I can't help you. I installed my display so it could be swung down after loosening screws for chain & tire maintenance. Some people have been known to spend $$$ to buy "bike stands" that hold the bike with the wheels in the air seat up. How those people change a tube out on the road is not explained to me. I roll the bike over, sometimes leaning it against a tree or a cable TV generator box or something. As I can't lift all of my 94 lb bike at once, a stand would help me not at all. I'd need a crane to lift the bike onto the stand. Maybe I should have been born with bigger arms, but then I'd be rock wall climbing or lifting weights or swimming or something instead of riding a bike.
I have to say I learned bike maintenance by doing it, not by watching videos on U-tube. Nor was there anybody to watch. Bike club members laugh at me as they blast by at 3 times my speed, or run stop signs all around me. I see them standing around sometimes waiting for the sag wagon to do the maintenance.
Thank you for the tips. I have done the above and will run through it again. I must have missed something. 😉
 
By the looks of the picture, with the chain in the highest gear ratio on the cassette cluster, that is where you want the chain to be when removing your rear wheel to make the flat repairs.

There should be a small toggle switch on the derailleur body, with an on-off setting. This is for the derailleur clutch. When removing the wheel for flat tire repairs, putting that clutch to the "off" position eases the clutch tension, allowing you to move the derailleur cage easier when lifting the tire off the frame. Don't forget to put the clutch setting back to "on" after repairs are made; this will prevent the chain from bouncing and scratching your chain stay when you hit a bump in the road. Removing the chain off the cassette with that clutch engaged can be tough and I suspect you did not release the clutch tension.

If you can't remove your display to flip your bike over & make repairs, you can always go with my "poor man's bike stand", consisting of a simple strap under your saddle. All you need is a good tree limb or something similiar to hold the weight of the bike.

100_5305.JPG

Poor Man's EBike Stand......about a dollar twenty five at Harbor Freight.

100_5307.JPG

Shimano XT derailleur. Note above the Shimano name you will see "On". There is a plastic grey toggle switch placed in the down position, to "Off". This is to relieve spring tension inside the derailleur clutch, allowing you to easier swing the derailleur cage when moving the wheel off the chain & frame. When repairs are done, place gray toggle clutch switch to the "On" position.....
 
First there is no such thing as a good flat. They are all bad. You can take the long link of the derailleur and push it down with your hand. You can also pivot the entire derailleur on the pivot bolt on the hanger by the frame. That chain may be locked between the frame and the small gear if you tightened the axle with the chain not being on a gear. Loosen the axle and you may have to drop the wheel again to loosen the chain. Then pivot the derailleur at both places and you will have a ton of slack available to put the chain on. On some bikes, it's easier to get all the slack available and take it off the pedal chainring. That makes it even easier by the back cassette and then easier to slip it on the chainring. Just be aware that there are narrow-wide chainrings and the chain must be on the correct indexing.
 
By the looks of the picture, with the chain in the highest gear ratio on the cassette cluster, that is where you want the chain to be when removing your rear wheel to make the flat repairs.

There should be a small toggle switch on the derailleur body, with an on-off setting. This is for the derailleur clutch. When removing the wheel for flat tire repairs, putting that clutch to the "off" position eases the clutch tension, allowing you to move the derailleur cage easier when lifting the tire off the frame. Don't forget to put the clutch setting back to "on" after repairs are made; this will prevent the chain from bouncing and scratching your chain stay when you hit a bump in the road. Removing the chain off the cassette with that clutch engaged can be tough and I suspect you did not release the clutch tension.

If you can't remove your display to flip your bike over & make repairs, you can always go with my "poor man's bike stand", consisting of a simple strap under your saddle. All you need is a good tree limb or something similiar to hold the weight of the bike.

View attachment 90855
Poor Man's EBike Stand......about a dollar twenty five at Harbor Freight.

View attachment 90856
Shimano XT derailleur. Note above the Shimano name you will see "On". There is a plastic grey toggle switch placed in the down position, to "Off". This is to relieve spring tension inside the derailleur clutch, allowing you to easier swing the derailleur cage when moving the wheel off the chain & frame. When repairs are done, place gray toggle clutch switch to the "On" position.....
Great photos! I can see my chain is thread through like yours. Yes, I did turn the clutch to off while doing my repairs and I am using a bike stand (I used to hand it precariously in the garage). I had the bike in the highest gear. I just put the clutch to ‘on‘ and it is running through the gears but the position of the pulley ’thingy’ is still straight behind where it should not be. 3 hours to the bike shop…. Still trying. I have a hunch it might be a simple fix. 🤔🚴‍♀️
 
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First there is no such thing as a good flat. They are all bad. You can take the long link of the derailleur and push it down with your hand. You can also pivot the entire derailleur on the pivot bolt on the hanger by the frame. That chain may be locked between the frame and the small gear if you tightened the axle with the chain not being on a gear. Loosen the axle and you may have to drop the wheel again to loosen the chain. Then pivot the derailleur at both places and you will have a ton of slack available to put the chain on. On some bikes, it's easier to get all the slack available and take it off the pedal chainring. That makes it even easier by the back cassette and then easier to slip it on the chainring. Just be aware that there are narrow-wide chainrings and the chain must be on the correct indexing.
Yes, I had better check the narrow-wide issue! When I manually pull the pulley system into position the chain is very slack! 😳🚴‍♀️
BE66ED02-C5A8-4399-A65F-1ABAF35E3F5D.jpeg
 
By the looks of the picture, with the chain in the highest gear ratio on the cassette cluster, that is where you want the chain to be when removing your rear wheel to make the flat repairs.

There should be a small toggle switch on the derailleur body, with an on-off setting. This is for the derailleur clutch. When removing the wheel for flat tire repairs, putting that clutch to the "off" position eases the clutch tension, allowing you to move the derailleur cage easier when lifting the tire off the frame. Don't forget to put the clutch setting back to "on" after repairs are made; this will prevent the chain from bouncing and scratching your chain stay when you hit a bump in the road. Removing the chain off the cassette with that clutch engaged can be tough and I suspect you did not release the clutch tension.

If you can't remove your display to flip your bike over & make repairs, you can always go with my "poor man's bike stand", consisting of a simple strap under your saddle. All you need is a good tree limb or something similiar to hold the weight of the bike.

View attachment 90855
Poor Man's EBike Stand......about a dollar twenty five at Harbor Freight.

View attachment 90856
Shimano XT derailleur. Note above the Shimano name you will see "On". There is a plastic grey toggle switch placed in the down position, to "Off". This is to relieve spring tension inside the derailleur clutch, allowing you to easier swing the derailleur cage when moving the wheel off the chain & frame. When repairs are done, place gray toggle clutch switch to the "On" position.....
Another try and it worked in “off”! 😁. Thank you! 🚴‍♀️
 
First there is no such thing as a good flat. They are all bad. You can take the long link of the derailleur and push it down with your hand. You can also pivot the entire derailleur on the pivot bolt on the hanger by the frame. That chain may be locked between the frame and the small gear if you tightened the axle with the chain not being on a gear. Loosen the axle and you may have to drop the wheel again to loosen the chain. Then pivot the derailleur at both places and you will have a ton of slack available to put the chain on. On some bikes, it's easier to get all the slack available and take it off the pedal chainring. That makes it even easier by the back cassette and then easier to slip it on the chainring. Just be aware that there are narrow-wide chainrings and the chain must be on the correct indexing.
Problem fixed! Now I’m noticing the wheel is no longer “true”. (“No good flat.”) I don’t think I’ll tackle the spoke adjustments. Nope… fixing the flat must have fiddled with the rim. Tire was on really tight! Thank you for your good help. 😬🚴‍♀️
 
Problem fixed! Now I’m noticing the wheel is no longer “true”. (“No good flat.”) I don’t think I’ll tackle the spoke adjustments. Nope… fixing the flat must have fiddled with the rim. Tire was on really tight! Thank you for your good help. 😬🚴‍♀️
Anna, if you know your rim was true prior to getting this flat, is it possible you rode for a distance on the flat tire, bending the rim in the process? I believe rims don't go out of true just on fixing a flat tire.

It's possible that the tire bead did not seat onto the rim properly. Visually check the tire for any abnormal looking bulge at the tire bead/rim interface, all the way around and both sides. If this is a presta tire tube, ensure the tube was installed with the valve centered in the rim hole and locked in place with the locking nut. If not, the valve can want to walk out of position.
 
Anna, if you know your rim was true prior to getting this flat, is it possible you rode for a distance on the flat tire, bending the rim in the process? I believe rims don't go out of true just on fixing a flat tire.

It's possible that the tire bead did not seat onto the rim properly. Visually check the tire for any abnormal looking bulge at the tire bead/rim interface, all the way around and both sides. If this is a presta tire tube, ensure the tube was installed with the valve centered in the rim hole and locked in place with the locking nut. If not, the valve can want to walk out of position.
Shall do! Yes, it is possible coming up the last hill that I rode on the rim unaware… 😬Great help! Thank you. 🚴‍♀️
 
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