Alfine hub in Thorn Rohloff dropouts

[PH]

Before I start a new project - has anyone done this?  if so anything I should be aware of? 
I have the hub and the frame and can't see there being any issue, but before i spend any money, I thought I'd check.

[rualexander]

Haven't done it myself but no reason why it wouldn't work.
In fact, SJSC sold some of there Raven frames off a few years ago equipped with Alfine rather than Rohloff hubs.

[geocycle]

I bought an alfine equipped RST a good few years back. It was all very neat, no reason not to do it.

[martinf]

I have a couple of Thorn frames with Nexus 8 Premium hubs in them. One is a clearance Raven Tour that I used to build my "new" utility bike, the other a Raven Tour Step Through used as a visitor bike.

Nexus 8 Premium is very similar internally to an Alfine 8 with the same needle roller bearings in the planets that are claimed to give greater efficiency than the plain bearings in the standard Nexus 8 hubs. The main differences between Nexus 8 Premium and Alfine 8 when I bought mine were a lower quality finish and provision for a roller brake rather than a disk. Shifters were interchangeable, my wife prefers the Nexus twist grip while I prefer the Alfine Rapidfire (on flat bars) or the Jtek bar end Shifter (on flat bars). Current model Alfine 8 hubs now have a reversed shifting direction compared to Nexus 8 standard and Premium hubs.

The chainline is not the same as a Rohloff, it is further inboard on the Nexus 8 Premium. So I used dished sprockets to bring the chainline close to that of the Rohloff in order to use the same bottom-bracket axle and chainset. I am fairly sure the Alfine 8 has the same chainline, and I think the Alfine 11 is probably also the same, though I haven't had one of the latter to play with.

Cable routing is different. Rohloff's two cables go to the LHS, Shimano Alfine and Nexus single cables all go to the RHS. So a bit less neat as I use ziplock ties. I have the cable going along the chainstay, but with Shimano hubs it is easy to change the orientation by using different anti-turn washers (done this when fitting a Nexus 8 Premium to my wife's Brompton).

I have had no problems using the Shimano anti-turn washers in the Thorn dropouts designed for Rohloff.

My reasons for fitting Nexus 8 Premium rather than Alfine 8: significantly cheaper (they were on offer at SJS at about £70) and no need for a disk brake.

My reasons for not fitting an Alfine 11, apart from the higher price: the Alfine 11 is reputed to be less forgiving with respect to bad cable adjustment and generally more fragile than Shimano's 8-speed models (important considerations on a visitor bike). And I don't need the extra range on my utility bike.

Shimano hub gears are supposed to be less efficient than Rohloff, this is confirmed by test results such as the link below:

https://www.cyclingabout.com/speed-difference-testing-gearbox-systems/

But I believe this test used the standard Nexus 8 (they also label it Inter-8), which is supposed to be less efficient than Alfine 8 and Nexus 8 Premium. In practice I don't notice any difference in efficiency between my Nexus 8 Premium bike and my Rohloff tourer on short to medium length local rides. The Rohloff is better in very hilly areas due to the wider gear range and on longish rides due to the close and even gear spacing, where I occasionally find the 22.3% jump between gears 5 and 6 on the Nexus to be a minor nuisance. Alfine 11 has the same close and even gear spacing as Rohloff, except for the big jump between gears 1 and 2, which wouldn't be an issue for me as on steep hills I often change 2 or 3 gears at a time on the Rohloff.

[leftpoole]

Regarding the mentions of chainline.
I notice that the modern 'trend' is for a silly little chainwheel with a dinner plate sized rear sprocket on a 11 speed cassette. This obviously produces the sort of chainline abhorred by serious and indeed mostly sensible engineer type cyclists.
So what is a couple of mm out- on a hub geared bike?

[PH]

Thanks for the replies.  I'm familiar with the hub, just checking there was nothing I'd not considered when using with these dropouts.  Thanks for the chainline reminder martinf, I think the current sprocket lines up with the middle position on a road triple, and I have just such a chainset, though maybe not the right BB.
It's a boredom Covid lockdown project, resurrecting my crashed Mercury frame.  I don't particularly have a use for it, I might build it light and use it as a fine weather fitness bike, ir it might end up as a posh shopper.  Either way, SJS had a B grade fork cheap, I have the rear wheel and enough spares that it won't cost much, I might treat it to a powder coat if I find I'm using it.  Being crashed I didn't want to sell it, though having had a good look I'm happy using.

[PH]

Regarding the mentions of chainline.
...
So what is a couple of mm out- on a hub geared bike?

In the case here the difference between the Rohloff the frame is designed for and the std chainline of an Alfine is around 10mm, so well worth noting.
Otherwise a few mm is probably not that important, though the bearings will be under a constant, if small, strain that wasn't intended and the chain won't be running at it's optimum.  That will have some effect on efficiency, you can look at the tests done on cassettes to get an idea of how much/little.  It'll also have some effect on the wear rate of all three components, again probably small and in the case of the Alfine and the components I'm using here,  cheap enough not to really be a consideration.
But getting it perfect is a one off job, set it up once and that's it for life. That's easy enough with the correct choice of chainset, BB and sprocket, the question for me would be why wouldn't someone do that.

[martinf]

But getting it perfect is a one off job, set it up once and that's it for life. That's easy enough with the correct choice of chainset, BB and sprocket, the question for me would be why wouldn't someone do that.

It was dead easy for me.

I used the same model of bottom bracket and chainset as I had on my Rohloff-equipped Thorn Raven Tour, but mounted the chainring inside the tabs on the crank instead of outside. With a dished sprocket fitted so as to move the chainline out by a few mm, the resulting chainline with the Shimano hub was virtually correct. To get it as spot on as I could judge (builders rule used as a straight edge placed on the chainring) I slid the eccentric sideways by a very small amount. That would probably also work with the eccentric on the Mercury.