Rohloff

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Shoogle
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Rohloff

Post by Shoogle »

I had my Rohloff wheel built by Big Al at Wheelcraft. Although he's a master wheel builder, he doesn't know much about Rohloffs. Anyway, it came with an OEM plate, but, although I have a Genesis Longitude, with track ends, I can't get the chain tight enough without pulling the stub bit too far back out of the drop out (I didn't think it would work). I have been using it, but the chain's so slack it often comes off . So, do I need a monkey bone, speedbone or some other kind of bone, and an OEM2 plate? I have a disc brake on the chainstay. I did look at 531colin's post on his Rohloff conversion but he's using QR and I'm threaded. Like 531colin, it's had a Tongsheng TSDZ2 fitted, but that's working fine and my chainline's fine.
Attachments
Chain.jpg
Dropout.jpg
slowster
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Re: Rohloff

Post by slowster »

531colin's thread, in particular this post - viewtopic.php?p=1562181#p1562181, shows exactly what you should do, i.e. fit an OEM2 with its supplied bolt. No need for a Monkeybone or Speedbone. You just need to determine which version of the OEM2 axleplate you need - there are two listed on SJS's website for TS (nutted axle) Rohloff hubs, one of which has a longer thread. I suggest you check the Rohloff manual, because the answer is likely to be in there. If a hard copy of the manual was not supplied with your hub/wheel, you can download it as a pdf from Rohloff's website.

https://www.sjscycles.co.uk/hub-spares/ ... ded-8228l/

https://www.sjscycles.co.uk/hub-spares/ ... oem2-8228/
rogerzilla
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Re: Rohloff

Post by rogerzilla »

Don't you just need a better ring and sprocket combination or (cheaper) a half link?
slowster
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Re: Rohloff

Post by slowster »

Incidentally, the routing of the cables to the external gear box looks sub-optimal. I suggest you re-route the cables along the downtube and chainstay.

If you want to keep the cables running down the seatstay, then I would rotate the gear box anti-clockwise to reduce the bends in the cable. The 12 bolt holes in the Axleplate allow the gear box to be rotated in 30 degree increments, and you may have to try a couple of positions to see how far the gear box can be rotated anti-clockwise and determine the optimum position. The time to do that would be when you fit the new OEM2 Axleplate.
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Shoogle
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Re: Rohloff

Post by Shoogle »

I'll try the OEM2 plate, similar to 531 colin's. The cable routing is just temporary 'til I get eveything sorted. I do want it up the seat stay though. To Rogerzilla: I shouldn't have to alter the gear ratios to get a tight chain. I have the largest rear sprocket - 21, so I can't go anywhere with that. Finally, I'm not familiar with half link.
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simonineaston
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Re: Rohloff

Post by simonineaston »

Sheldon describes the half link on this page here.
S
(on the look out for Armageddon, on board a Brompton nano & ever-changing Moultons)
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Shoogle
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Re: Rohloff

Post by Shoogle »

Thanks Simon. I hadn't even heard of half link 'til last week. Don't think it's for me.
PT1029
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Re: Rohloff

Post by PT1029 »

A half link has bent plates so it is outer plates at one end, and inner plates at the other end. This means you can alter the chain length by 1 link rather than a pair of links. an example here: -
https://www.sjscycles.co.uk/chains/kmc- ... ting-link/

If you push the pins in and out in the right order, you can with trail and error make your own (need a vice for bending the plates). I have done such for the linking chain on our runabout tandem. It hasn't broken yet, and not too far to walk to get home (or to get home on hind quarters doing the pedalling...!). I did this with a cheapish chain however, I doubt you could do it DIY with a fancy pressed over pin end type of chain though.

All that said, you have almost no chain adjustment, as you can't move the wheel back (the non turn thingy will be out of the drop out), and you need to keep some spare dropout in front of the axle to allow you to slacken/derail the chain to get the wheel out.

Question.
Are the dropouts designed to take the rotational forces of the Rohloff axle? The drop outs don't look super sturdy for such forces. I have seen a photo of a similar but longer dropout having been spread open by the forces of the Rohloff axle.
bent dropout.jpg
If you can rig it so the dropout does not take the stress, it should be ok.
PH
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Re: Rohloff

Post by PH »

slowster wrote: 27 May 2022, 6:52pm 531colin's thread, in particular this post - viewtopic.php?p=1562181#p1562181, shows exactly what you should do, i.e. fit an OEM2 with its supplied bolt. No need for a Monkeybone or Speedbone. You just need to determine which version of the OEM2 axleplate you need - there are two listed on SJS's website for TS (nutted axle) Rohloff hubs, one of which has a longer thread. I suggest you check the Rohloff manual, because the answer is likely to be in there. If a hard copy of the manual was not supplied with your hub/wheel, you can download it as a pdf from Rohloff's website.
I'm at a bit of a loss to understand where you're suggesting the torque bolt goes? I can't see a slot on that dropout that would allow it to move as the chain was adjusted.
PH
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Re: Rohloff

Post by PH »

In the absence of a slot for the torque bolt, I'd use a Monkeybone, very straightforward, adjust the brake for the new wheel position and the OEM2 plate fits perfectly. Or use a tensioner, it's not my preferred option, but it's no big deal either, I have one on my folder and the only difference I notice is it's something else needs cleaning.
If you need a threaded OEM2 plate I have one spare (Half price?), standard length, my Surly has odd dropouts and is better with the long version.
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531colin
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Re: Rohloff

Post by 531colin »

Just fit a chain tensioner, and the OEM torque arm with the bolt in the handy dropout slot

One dark wet cold night you will puncture.
..........with a chain tensioner "all" you have to do is .....
put it in gear 14
undo the external cable box
unhook the chain from the chainwheel
undo the axle Q/R (or nuts.....why nuts?)
pull the wheel out of the dropouts, unhook the chain and you have the un-encumbered wheel in your hand

Re-assembly is pretty much the reverse.....
hang the chain on the sprocket
slide the wheel into the dropouts; use the cable box arm to guide the torque arm onto its bolt head on the dropout (my modified ISO adapter makes engaging the torque arm with its bolt head almost automatic)
slide the wheel all the way forward until it stops, and do up the Q/R (or nuts)
hang the chain on the chainwheel
re-connect the external cable box

I can hear all the neat freaks and purists saying how you don't need a chain tensioner, its an added complication.....
but among all the inherent complications of the Rohloff and disc brakes, the chain tensioner is a dead simple bit of kit which makes all the other stuff easy to live with ......well, easier, anyway.

Do you really, really want to be faffing about trying to position the wheel to get the chain tension right, then moving the disc brake a couple of millimetres to line up properly? If the chain tension is really right you have to be able to move the wheel forward to get the chain off.

Lifes too short! I bung the wheel in until it stops, and all the alignments are back exactly where they all started.

ImageIMG_5321 by 531colin, on Flickr

ImageIMG_5310 by 531colin, on Flickr

Pictures show the torque arm and its associated bolt in the dropout slot, and my modofied ISO adapter to locate the arm on the bolt head
theres a bit of white paper behind the dropout in the second picture, trying to show the torque arm location clearly.....its seen better in the first picture, taken from the wheel side of the dropout

Brucey was a bit cautious about using the Longitude dropout slot for the torque reaction arm, he reckoned there was a possibility of the slot opening up, and if you really wanted to use it, you should fill in the cutouts in the dropout with bits of ali. filed up and glued in.
cycle tramp
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Re: Rohloff

Post by cycle tramp »

If I remember rightly when I borrowed a rohloff, you can unbolt the plate with the stubby bit from the rest of the hub.

If that is still the case then you could unbolt the plate and then swing it 180 degrees and bolt it back to the hub. By doing this you've effectively swapped positions of the stubb and the wheel bolts allowing for better chain adjustment...

..although I'm with 531Colin, just get a chain tensioner... and if that was my frame in 531Colin's photo I'd think about getting some wax oil in the frame via the breather hole. How big is that hole...?!?
Motorhead: god was never on your sidehttps://www.google.com/search?ie=UTF-8&client=m ... +your+side
slowster
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Re: Rohloff

Post by slowster »

PH wrote: 27 May 2022, 9:03pm I'm at a bit of a loss to understand where you're suggesting the torque bolt goes? I can't see a slot on that dropout that would allow it to move as the chain was adjusted.
You are right. I had completely forgotten that 531colin is using a chain tensioner, and so did not need to be able to adjust for chain wear. In fact I had forgotten much of what I myself had posted.

On balance I think I would prefer 531colin's set-up with a chain tensioner to using a half-link with the existing OEM1 Axleplate.
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Shoogle
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Re: Rohloff

Post by Shoogle »

Threaded axle because, according to the Rohloff manual: "Threaded axle TS - The Rohloff SPEEDHUB 500/14 versions with a threaded axle are required for frames with horizontal dropout slots", although 531 colin has the same bike with QR.
531 colin's original post about the Rohloff went to 6 pages!
pwa
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Re: Rohloff

Post by pwa »

Has the OP made sure the chain is not simply too long? It isn't unusual to have to take off a few links to get the length within the range that will work. I'm guessing that process has been gone through and no more can be taken off without the wheel being impossible to remove with an intact chain?

Incidentally, the end result when all is working well (and if no chain tensioner is employed) should be a chain with a tiny bit of slop still present. It won't run well with a very taut chain.
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