Replacement for 7 speed Shimano derailleur

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So i got my wife a 7 speed bike that was barely used it still had the factory grease on the chain.

So the first problem was that the rear derailleur wanted to hit the spokes of the wheel if I put it into lower gears so I thought I know how to fix that, shorten the chain.
So I removed 5 links and took it for a spin around the block. I only made it halfway around the block when I tried to shift it to the highest gear and then back to the lowest the derailleur hit the spokes and tore it apart and bent the mount for the fender.

So now I'm on a search to find a new good derailleur that doesn't cost more than the bicycle.
It is a huffy Norwood.
Any ideas I don't know anything about compatibility. Also I we'll have to replace the chain because it twisted several links what is a good cheap chain that I can go with?
We are not avid riders we just ride every now and then for fun. No long distances or crazy terrain just literally Sunday riding.

20190914_113659.jpg
 
Unless I am misunderstanding the problem, it seems that you misunderstand derailleurs. Either it was bent and needed bent back or replaced, OR it just needed the adjustment screw turned so it stopped at the last gear alignment instead of continuing to move into the spokes. Removing chain links should never be needed. This is the thing about cheap department store bikes, often they are not adjusted correctly, just slapped together.

Which model of Shimano is it? Maybe get the same thing, probably costs about $15-$20 if you shop around for the best price. However the cost of that plus the chain... I'd be tempted to keep an eye on craigslist ads for a better quality, used bike. They can often be had for around $50.
 
If the bike was like new the odds of the chain being 5 links long is very small. Hitting the spokes in 1st has nothing to do with the chain, as said it's either a simple adjustment of the L screw or something is bent, either the derailleur or the hanger.

It looks like this one on Amazon: Shimano 7 spd and this chain will work: 7 spd chain so you'll have around $30 in parts. There are 2 different mounts used on rear mechs, make sure you get the same.

You'll want to count the links the chain had before you cut it and make the new chain that length. Do you have a chain tool like this? chain tool It's pretty hard to press a chain apart and get back together with the correct spacing without one. If you just squeeze it back together you'll bind the chain.

A bicycle drive line isn't rocket science but there is some knowledge needed to get it to work properly. Probably a ton of Youtube videos how to adjust the rear mech. You mentioned something bent on the frame? If the frame is bent where the derailleur mounts you've got a problem, it's difficult to get it lined back up correctly if you don't know what you're doing. It can be done with an adjustable wrench and trial and error.

You can try to get it all back together with Youtube help, you could find a friend who knows bikes to put it back together and teach you, or you could take it to a shop.

FWIW this was a $99 bike at Walmart.

Good luck.
 
I misstated some of that. The chain was very much too long and it seems that is normal for new cheap bikes. I thought that shortening the chain would bring the derailleur up and farther from the spokes which it did just not nearly enough.
I knew the derailleur was shot but i thought i could make it last until i could order a new one that is where i was wrong
I wont be paying a bike shop because i dont want to i got a 10$ bike for my wife partly as a project.

I just wondered if anyone who knows more than me would have any idea if i can just buy the first derailleur that says for 7 speeds that i see or if it is more specific than that.
I did not get a chance to tune the derailleur because it got distroyed far to soon .
I remember the thrashed junk bikes i rode as a kid had all metal gears and frames on there derailleurs and i would like to find some like that again. Weight doesn't matter to me.
And about the chain i saw someone on here mentioned a reasonable priced chain that was durable but i dont remember where i read it.

I want to tinker on this bike and i dont pay for mechanical work that is what i get paid for. ...€
 
Originally Posted by AZjeff
If the bike was like new the odds of the chain being 5 links long is very small. Hitting the spokes in 1st has nothing to do with the chain, as said it's either a simple adjustment of the L screw or something is bent, either the derailleur or the hanger.

It looks like this one on Amazon: Shimano 7 spd and this chain will work: 7 spd chain so you'll have around $30 in parts. There are 2 different mounts used on rear mechs, make sure you get the same.

You'll want to count the links the chain had before you cut it and make the new chain that length. Do you have a chain tool like this? chain tool It's pretty hard to press a chain apart and get back together with the correct spacing without one. If you just squeeze it back together you'll bind the chain.

A bicycle drive line isn't rocket science but there is some knowledge needed to get it to work properly. Probably a ton of Youtube videos how to adjust the rear mech. You mentioned something bent on the frame? If the frame is bent where the derailleur mounts you've got a problem, it's difficult to get it lined back up correctly if you don't know what you're doing. It can be done with an adjustable wrench and trial and error.

You can try to get it all back together with Youtube help, you could find a friend who knows bikes to put it back together and teach you, or you could take it to a shop.

FWIW this was a $99 bike at Walmart.

Good luck.

The part that was bent was the frame of the derailleur itself.
 
Just make sure it mounts the same as what's on the bike. It most likely has a plate that fits under the axle nut. The other way is a separate mounting bolt that has it's own hole near the axle. Can't tell from your pic. Tourney rear shifters can have either mount.

You don't want the chain so tight that if she would shift into the large front and large rear sprockets that the chain is under extreme tension and bends things up again.
 
Originally Posted by AZjeff
Just make sure it mounts the same as what's on the bike. It most likely has a plate that fits under the axle nut. The other way is a separate mounting bolt that has it's own hole near the axle. Can't tell from your pic. Tourney rear shifters can have either mount.

You don't want the chain so tight that if she would shift into the large front and large rear sprockets that the chain is under extreme tension and bends things up again.


That makes sense. Well Amazon here i come
 
I will check the hanger but the old derailleur was really sloppy in the pivot. I had never seen one that poorly made. I think either the previous owner hit it somehow or i tore it up cramming it into my tahoe on top of my tools to get it home. The bike still had the sale sticker on the frame when i got it. Its just a cheap bike but i would rather tinker than ride anyway so it should be a good one for us. ...€
 
Originally Posted by Zahndkile
Are stainless steel chains any good? This bike is living outside so i thought i might go stainless.


I sold a handful of them back in the day and never received a complaint, but no first hand experience. Why don't you go with something like Amsoil HDMP for a chain lube if you are worried about exposure? Or fluid film?
 
If it's a low end bike then storing outside will be rough on everything else also. Not that it's kind to a high end bike either, but, the cables will eventual degrade too.
 
Originally Posted by MrQuackers
I would upgrade at least to the Altus.

Tourney is junk.

I was about to say the same thing. But a bike that uses Tourney likely won't be able to use Shimano's nicer parts. For one, Huffys and Dorel's mass-market lines(Schwinn/Mongoose) don't have a separate rear derailleur mount. Only the flimsy Tourney stamped steel mount and t-bolt for the drop-out. Just get another Tourney rear mechanism and a SRAM 7-speed chain with a quick link, no tools required to install the new chain but you still need one to "cut" the chain to the original length(but since the SRAM quick link is a functional link, cut the new chain with one less outer link) and to remove the old chain.

Then you will need to adjust the travel limit screws and cable tension to ensure smooth shifts. You can find a video on YouTube on how to do this.
 
I am at Fred Meyer right now perusing the bicycles. Lookie here, a Schwinn Suburban with a Tourney derailleur and the frame actually has a mount tang for it.

Nice looking bike on sale for $188

Not your 70's Suburban

TOURNEYonSchwinnSuburban.jpg
 
I am at Fred Meyer right now perusing the bicycles. Lookie here, a Schwinn Suburban with a Tourney derailleur and the frame actually has a mount tang for it.

Nice looking bike on sale for $188

Not your 70's Suburban

View attachment 17019

The bike term is "derailleur hanger", if you're talking about that black painted aluminum thing connecting the derailleur with the hub bolt. The idea is if you hit a rock or log or other thing with the derailleur hard enough, you'll mess up the derailleur and hanger, both of which are substantially cheaper than a new frame.

Generally speaking, you'll want to set the chain length to (paraphrased from "Zinn and the Art of Mountain Bike Maintenance") overlap by one full link (complete link pair) where the chain comes together when it's on the largest chainring and largest cog, and is NOT threaded through either derailleur.
 
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