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I have a Giant Escape N8.

Unfortunately the nexus 8 hub is damaged, the wheel is also damaged, so I need to replace the whole wheel and the nexus 8. The chain also needs to be replaced, and I suspect the front crank might be in for a change as well.

Can I instead install a rear derailleur in place of the internal hub, as I need to replace the whole wheel anyway? What would I need to replace to make this work?

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    This is getting real close to "economically unfeasible" You might be best to sell it as a parts/donor and buy a replacement bike. Sorry.
    – Criggie
    Jun 13 '17 at 20:15
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It depends on the spacing and shape of the dropouts. As I remember, Nexus 8 is 120mm OLD spacing on the frame. That stands for "Over Locknut Distance". It's the distance between the rear dropouts. Most geared hubs are going to use either 130 or 135mm OLD. So if it's not already that wide, and it's a steel frame, it may be able to be cold set that wide, if it's aluminum, I wouldn't really chance it.

The mounting for the rear derailleur itself is going to be the other big hurdle. Does the frame have a derailleur hole next to the axle for threading on a direct mount derailleur? If not, a hanger that matches the dropout style may be in order. Depending on the type of dropouts(front facing, rear facing, etc) it may be as simple as installing a derailleur that has the hanger built into it, or you may have to buy a "problem solver" part that adds a hanger to the frame.

The last hurdle you'll run into, you say you may need to replace your cranks and chain, that's wonderful news. Because you'll need to get a chain that is compatible with whatever speed shifting system you are looking to install, and a crank(or at least chainring) that is also compatible with that chain.

Then you just install all of that, in the process altering the frame to match if necessary, and install a shifter that works with the derailleur and you're good to go.

Usually, this alteration is more hassle and cost than it's worth. It's usually more worthwhile to get a new 8-speed Nexus hub or buy a bike with gears. But that's completely up to you.

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  • Yeah I see this will be a big hassle. The frame is aluminium and doesn't have any holes for the derailleur. I was thinking about this because the bike is only 3 years and the hub is gone, I serviced it twice a year so I don't know how the bike got to this state. Do you have any advice to not let a bike go like this?
    – simao
    Jun 13 '17 at 19:50
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    Nexus 8 should be 132 mm OLD, so no respacing required. See this chart. The easiest thing to do is put in another IGH, or go single speed.
    – Batman
    Jun 13 '17 at 19:53
  • That removes one hassle, but still a pain. Jun 13 '17 at 20:05
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    OLD, doesn't that stand for Over Locknut DISTANCE?
    – Carel
    Jun 14 '17 at 17:19
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    @Carel You know what? It looks like I've always misquoted that, I'll edit it in my answer. I mean really, I've trained many mechanics in the last 18 years, and always said diameter. But yeah, just looked it up, and it's distance. Jun 14 '17 at 17:39
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This isn't going to be nice, because the frame doesn't have a derailleur hanger built in, or routing for the derailleur (which you'd have to hack on with clamp cable stops or something).

On a normal frame, one would install either a derailleur with a built in claw (e.g. Shimano Tourney RD8153)

enter image description here

or an adapter claw (e.g. SunRace Rear Derailleur Adaptor Claw)

enter image description here .

(Pictures from Sheldon Brown's site)

But your bike doesn't have horizontal dropouts -- it has forkends. So, you could try a chain tug with a derailleur hanger on it: enter image description here

This one is from Problem Solvers and is about 30 USD, but there are others from SunXCD, Origin8 among others. Then, bolt on a derailleur as usual.


Note that even if you get a derailleur on using the chain tug with derailleur hanger, you still need:

  • Wheel
  • Derailleur
  • Cassette/freewheel
  • Shifters
  • Cable routing
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  • Nice Visuals Batman! I like it Jun 13 '17 at 20:07

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