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I want to know whether my frame is compatible with any kind of derailleur hanger, as I want to install standard gears. Due to my Nexus 8 speed hub being really quite uncomfortable and faulty since getting the bike (it gradually got worse).

I can just invest into a Rohloff hub and all will be well, but that's a big chunk of money for me. I'd prefer to switch (if I can) to a simple derailleur system, which I can easily maintain too.

See this link for my exact bike, it's possible to zoom in on the rear dropout too, as below:

I know there's no direct fixture for a hanger, but are there alternative ways to fit hangers onto frames like this?

enter image description here

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    Your other option is to buy an entire derailleur bike - would probably still be cheaper than a rolhoff hub.
    – Criggie ♦
    Commented Mar 17, 2021 at 20:40
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    What's the warranty situation on your Nexus hub? Sounds like the first thing to do is to try to get Shimano to fix/service it.
    – thosphor
    Commented Mar 18, 2021 at 11:47
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    @thosphor I'm around 1 year and 6 months into it. I believe all shimano parts have 2 year warranty so yes this is an option. Been trying to contact my nearest Shimano servicing centre, however the last two times I called there was no answer. I'll keep trying though.
    – rhysmatthew
    Commented Mar 19, 2021 at 0:24
  • @Criggie I'm thinking about doing this to be honest, if I can sell my current one to help me out I should be okay, it's just getting it working and sellable.
    – rhysmatthew
    Commented Mar 19, 2021 at 0:25
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    @Criggie - Long awaited update, but Shimano did warranty the hub with new internals and my frame was warrantied because of a crack too. I then sold the bike and built myself a custom Surly bike with a derailleur setup (a lot happier tbh). In the future I will definitely give Rohloff a go but not yet. Thanks for your advice.
    – rhysmatthew
    Commented Aug 24, 2021 at 9:39

4 Answers 4

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There is no good way. One could imagine ways of contriving a low-end claw-type derailleur on. Don't do that.

Nexus hubs are usually reliable. In some places in the world, there are lot running around without issue. That you've had chronic issues suggests either damage, defect, or a setup issue.

Some number of Nexus and Alfine bikes have made it into the world with mismatched cassette joints and shifters from the factory. It is a maddening problem until you've figured it out.

There are steps between what you have now and Rohloff, if it came to replacing the hub. I recommend taking it to a shop that really knows internal hubs. They are robust but have their quirks and unique procedures and things to check.

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  • Thanks for your reply, I hoped there would be a way but I think you're correct here. I should of explained further though in regards to the Nexus hub. It's only when I'm climbing hills or putting a lot of pressure onto it. It seems to snag on the inside and makes a loud clicking noise every second or so (has become quite frustrating). I've replaced the cable too and re-aligned the yellow dots, which helped slightly but now it's still being faulty. It slowly got worse upon buying the bike, Rutland Cycles wouldn't exchange it either as it was a couple weeks over the warranty period.
    – rhysmatthew
    Commented Mar 19, 2021 at 0:41
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    @rhysmatthew The hub has a 2 year warranty from the purchase date from Shimano, if you're still in that period. The reason I recommend taking it someplace that really knows internal hubs is that Shimano IGHs are more serviceable and parts-supported than people sometimes realize if there's an issue. Sometimes things break and can actually be fixed pretty easily. It's viewed as byzantine and impossible by some shops, but all you really do is pull the core, break it down into its subassemblies, clean everything and look for the broken thing, order that and put it back together lubed.
    – Nathan Knutson
    Commented Mar 19, 2021 at 0:49
  • Long awaited update, but Shimano did warranty the hub with new internals and my frame was warrantied because of a crack too. I then sold the bike and built myself a custom Surly bike with a derailleur setup (a lot happier tbh). In the future I will definitely give Rohloff a go but not yet. Thanks for your advice.
    – rhysmatthew
    Commented Aug 24, 2021 at 9:40
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I've never tried them, but some suppliers such as Wheels offer an emergency hanger which is held in place by the clamping of the quick release. while such a solution may allow you to attach any modern derailleur to your bike, it would not be easy to live with, as removing and reinstalling the rear wheel would become an ordeal. Also, the shifting on many systems may suffer from the derailleur mount being further outboard than intended.

I'm not sure whether this relates to your hub's specific problem, but aside from the cassette joint issue Nathan mentioned (and I will note there is a dedicated cassette joint for belt drives), Shimano internal gear hubs can suffer as a result of excessive belt tension, and some manufacturers have shipped Alfine bikes with belt tensions too high from the factory. The correct tension for a single speed belt drive may be too high for an Alfine hub. Most of the belt-drive related posts on the S-Tec forum relate clicking in Alfine hubs to too high tension.

Consider this post from a Shimano product manager 7 years ago:

Current 8 speed hubs use roller clutches instead of pawls so they should be silent when pedaling forward. We hear this complaint a good amount when our hubs are used with belt drives. The heart of the issue seems to be that internally geared hubs like to have relatively low chain/belt tension and that belts need to be at relatively high tension to stay on. You may need to fine tune the belt tension a little differently than you generally would in order to make sure that you are at the very low end of the acceptable tension range recommended by Gates.

We've also seen issues with noise coming from the belt drive cog moving on the driver unit of the hub. It may be worthwhile to add a little grease to the cog/driver unit interface.

In these cases it can also be helpful to reach out to the companies that make the cog and belt (they may both be Gates but anyone could be making the cog).

While the Shimano recommendation seems to be to set the belt drive at the low end of the drive manufacturer's prescribed range, Alee Denham of CyclingAbout makes the case for running even lower belt tension on the basis of improved efficiency:

That said, if you use a particularly stiff frame, you can lower the belt tension below the recommendation. You didn’t hear this from me, but I’ve been slowly reducing the belt tension on my KOGA slowly over the last year, and frankly, it’s getting ridiculous. My belt can now touch my chainstay, it’s so far beyond the minimum that I can’t even measure it – and I’m a very strong rider, with a heavy load, riding up incredibly steep mountain roads.

At my approximate belt tension, and at the power outputs I push, my belt is likely running the same or lower friction than a chain. I only recommend trying this with a belt snubber fitted, which will make sure the belt stays on, even if the belt tries to skip.

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short direct answer:

Yes, you can, you just need to buy a derailleur hanger (for an example check this old answer) and then measure all the various components to get the correct chain line (it may involves changing the bottom bracket). My opinion: you have a frame ready to accept a belt, it is a waste to use it for a chain-nased drivetrain. You are probably better off by selling the current setup and buying a chain-based bicycle.

Check also this answer:

Answer to a question you didn't pose:

What you describe seems a specific issue with that very specific hub. I think the easiest is to change the rear hub: you have an unlucky one, a newer one would do wonder.

I really think the issue you have is specific to your hub, specifically your hub with serial number xyxyxyxy, not with the specific model of hub you have (or with the brand in general).

Disclaimer: I do not work for Shimano, I suggest swapping the hub with any hub, you mention Rolhoff but it is not the only alternative manufacturer ...

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    do you think it might be worth mentioning that the example hanger you linked (SRAM UDH) is a new hanger standard promulgated by SRAM to get more new bikes to share a common part (see Wheels Mfg's catalog of hundreds of hangers/dropouts) and not a universal retrofit?
    – Pisco
    Commented Mar 18, 2021 at 12:49
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    @Pisco Thanks, I did not know, the universal is in the name and is not an adjective, it tricked me!
    – EarlGrey
    Commented Mar 18, 2021 at 13:02
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    Thanks for the advice @EarlGrey. Shimano did warranty the hub with new internals in the end and my frame was warrantied because of a crack too. I then sold the bike and built myself a custom Surly bike with a derailleur setup (a lot happier tbh). In the future I will definitely give Rohloff a go but not yet.
    – rhysmatthew
    Commented Aug 24, 2021 at 9:58
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Your bike has a belt drive. That cannot run a derailleur setup at all - you would have to rebuild the bike with a chain.

That means buying a chainring, rear wheel, cassette, chain, derailleur, shifter, and cabling. This would be expensive.

Looking at the almost vertical dropout, there is no space to fit a claw hanger - it would force the axle down a bit and potentially out the bottom, risking the axle moving under load.

Hanger would end up angled backward too far which would make the rear mech angle backward too, which will reduce chain engagement on teeth of cogs.

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    True, but entry-level components are surprisingly cheap. Everything you’ve listed can be had for ~200 to 400€ at Shimano Alivio or Acera level. The bike costs more than 1000€ new. The main problem would be mounting rear and front derailleurs.
    – Michael
    Commented Mar 18, 2021 at 6:34
  • @Michael fair enough - I keep forgetting that pricing proportions are different around the world. If it works financially for OP, then that's a good idea
    – Criggie ♦
    Commented Mar 18, 2021 at 6:56
  • @Michael, exactly my thinking. If I can somehow get a hanger on there I could run a 1 by setup and save a ton of money. However it's looking like the best option is to sell and build a new bike from scratch. I kind of like that option though, just need to get this bike sellable.
    – rhysmatthew
    Commented Mar 19, 2021 at 0:32
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    @rhysmatthew You'd need a replacement rear wheel hub or maybe a complete wheel. Trying to put a cassette in the space where one drive belt pulley was, won't fit. Could you measure the OLD of the frame/wheel? If its 135 you're okay, if its weird then there may be bending of the frame too, which is only possible with steel.
    – Criggie ♦
    Commented Mar 19, 2021 at 5:47

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