Rohloff Gear Ratios - Possible to get wider setup?

[Psamathe]

I'm in early stages of considering upgrading my ICE Sprint X Tour to a Rohloff.

Currently I've triple at front, 10-speed at back. Following advice I got here when purchasing I'm very happy with the gearing I have which gives me 16" to 103" (gear inches). Low enough for hills and high enough for as fast as I'll need to go. Maybe a bit lower than 16" would be helpful as all my cycling to-date has been East Anglia and Netherlands (without hills).

I'm vaguely in early stages of thinking about Rohloff but checking and the range is limited. Closest I can get would be with a 36 chainwheel giving 16.2” to 85”. Happy with low but 85" is a bit low.

I did wonder about a double at the front and maybe a short derailleur that doesn't move at the rear to act as a chain tensioner that accommodates the difference from the front but even if it does work t all seems a bit of a bodge.

I've never been keen on the Slumpfh things (sorry about spelling).

Are there any alternatives or ways to get a wider range?

Ian

[[XAP]Bob]

A front changer and a short derailleur are perfectly valid approaches.

Tiger will be along in a moment - IIRC he has a schlumpf up front with two chainrings, as well as two sprockets on the hub.

I'm getting a rolhoff set up for the mango, which will be paired with the schlumpf HSD - cutover will be a little over 25mph, and will stay in the top half (the more efficient half) of the hub for higher speeds (obviously overdrive is the lower efficiency of the shlumpf, so I hope taking out one gear train at the back somewhat compensates)

[slowster]

If you only use the 16" gear when on tour with the extra weight of panniers, one option might be to fit a smaller sprocket to the Rohloff for day to day riding, and a larger sprocket when on tour. Obviously that would not give you the wider range you are seeking, but it might be a good compromise, since the sprockets are relatively inexpensive, easily changed, and the set-up would keep the basic simplicity of a hub gear like the Rohloff. I assume you would need a chain tensioner anyway with a recumbent trike, which should be sufficient to cope with the small teeth difference between the sprockets.

The link below is an illustration of switching between the standard supplied 16t sprocket and a 19t sprocket, combined with a 42t chainring (I would generally choose larger chainrings and sprockets where possible). The 16t gives 19"-100" and 19t gives 16"-85".

http://www.gear-calculator.com/?GR=RLSH ... 6&UF2=2075*

* I've set the wheel size to give the 16"-85" range you mention as a baseline: it may not be the actual wheel size of your trike, but it demonstrates the relative effect of changing the sprocket.

[PH]

I'm a Rohloff fan, but my opinion is if you start using multiple sprockets or chainrings, much of the advantage is thrown away.
It is possible, the handbook gives the options and we've had similar threads before:
viewtopic.php?f=24&t=140937

EDIT - I haven't found the thread, maybe it was elsewhere, there was someone on an upright tourer with double chanring and Rohloff tensioner, but no front mech, changing by hand depending on what sort of day it was going to be.

[Psamathe]

My reasons for thinking about a major expense (it's not just the hub but a new wheel, new shifting system, cables, etc.) is that on recent tour loaded I was finding

• the rear derailleur was not changing nicely and jumping gears sometimes. I was often cycling along twisting the cable adjuster (which is very conveniently located on the steering bars) but no adjustment seemed to improve it. Unloaded and it was fine so I assume my playing/setting was not disaster.

• also I was finding I was often ending up stopped somewhere in a very wrong gear. I appreciate this is "user failure" but not something that happens cycling around at home

• the rear derailleur never grounded, neither did the frame but my side panniers did on quite a few occasions (no damage, not serious) and they were not hanging below the height of the frame or derailleur. The pannier grounding was often on ramps particularly when trike titled not going straight up ramp. Also that the rear derailleur is close to the wheel and thus less affected by tipping but it did concern me as it is low, even on a 26" rear wheel

So it certainly is not a need and it is a lot of money to justify and the oil change/service frequency is a concern (particularly for longer tours I'll hopefully be doing in future).

Ian

[Psamathe]

A front changer and a short derailleur are perfectly valid approaches.

Tiger will be along in a moment - IIRC he has a schlumpf up front with two chainrings, as well as two sprockets on the hub.

I'm getting a rolhoff set up for the mango, which will be paired with the schlumpf HSD - cutover will be a little over 25mph, and will stay in the top half (the more efficient half) of the hub for higher speeds (obviously overdrive is the lower efficiency of the shlumpf, so I hope taking out one gear train at the back somewhat compensates)

I've only ever seen pics of the schlumpf but I'd always had the impression it has a single chainring with some gearing between crank arms and the chainring. Maybe I have the wrong impression.

So far I've only discussed options with ICE and they only offer limited configurations e.g. 30T or 42T chainrings but they do say you can fit a chainring of your choice so onlyhttps://forum.cyclinguk.org/viewtopic.php?t=153532 constrained on what they stock or supply.

My worry about the schlumpf is that it is a very specialised thing and I assume low volume and vague concerns about longevity of solution (e.g. if it went wrong and company had suffered "tough times" ... The significant expense of the rolhoff becomes dependent on a specialised bit of kit from another company. Maybe I'm being paranoid but companies do come and go.

Ian

[PH]

the oil change/service frequency is a concern (particularly for longer tours I'll hopefully be doing in future).
Ian

It's 5,000km or annually, I've stuck to that for the warranty period, then been a bit more relaxed. They get done every year, I don't count all the km's, if it's been a wet winter I'll do an extra one in the spring, or before a long tour. Buy the oil in a decent quantity and it's a few quid per change, £2.80 for me though I haven't bought oil for a while.
If you're on a long tour, the kit and enough oil for a few changes can be packed in the same sort of space as an inner tube.

[slowster]

the oil change/service frequency is a concern (particularly for longer tours I'll hopefully be doing in future).

I don't understand that. It's a 5,000km (or 1 year, whichever is first) oil change interval. The procedure is fairly simple and straightforward, and the oil change kit does not take up much weight or space. Rohloff's own and Thorn's videos below show how easy it is.

[Psamathe]

the oil change/service frequency is a concern (particularly for longer tours I'll hopefully be doing in future).

I don't understand that. It's a 5,000km (or 1 year, whichever is first) oil change interval. The procedure is fairly simple and straightforward, and the oil change kit does not take up much weight or space. Rohloff's own and Thorn's videos below show how easy it is.
...

Comes in part from my lack of knowledge on Rohloffs (how to service and how much the distance can safely be pushed) and part from 3+ months touring at 1000+ per month and you're exceeding the limit.

If it can be DIY and you say parts small to carry then not an issue.

Ian

[UpWrong]

Sounds like a 34/44 compact double up front and a short cage derailleur at the back would do the job.

Incidentally, your RD shifting problems are likely to be a bent hanger. I've used my hanger alignment tool lots, although Brucey reckoned that screwing in a wheel on a threaded axle in the hanger to check and adjust alignment worked better.

[Tigerbiten]

If I was setting up a Rohloff on a bent trike without a Schlumpf drive on a bent trike ......

I would go for a 30/39/50 road triple.
That would give you 4 more gears up/down over the standard range.
On a 26" wheel then aim for as big a sprocket as possible.
So 30t / 1.9 = 16t sprocket for 13.6"-119" or a 17t at a push for 12.8"-112".
On a 20" wheel with a 13t sprocket that's only 12"-105".
If you plug the numbers into a gear calc, you'll see the overlaps line up offset by 2.
That make changing chainrings very predictable.
And the Rohloff chain tensioner will cope with the 20 tooth/10 link difference between chainrings.

If going for a double then something like 30/44 will give you 3 extra gears.
The big chainring needs to be 1.466x bigger than the small to line the overlaps up.

My twin chainrings also give my 3 extra and then you also add the 7 extra from the Schlumpf HSD for a grand total of 24 unique gears.

Luck ..........

[hercule]

You can use a derailleur/Sturmey 3 speed combo as I have done - it works well, you can certainly use up to a 10 speed cassette, maintenance is minimal and cost is low. I built a CS-RF3 hub into a Sun rim and have had a couple of years use out of it so far. It’s currently off the trike because it has become very rattly: this tends to happen with SA hub gears in small wheels but MickF of hereabouts has posted a fix… I just need to get around to doing it! Gives me a mind-boggling 81 gears and in particular a set of high top gears for charging downhill.

[Tigerbiten]

I looked into it fully ~12 year ago when I last upgraded my bent trike.

A plain derailleur setup gives around a 6x gear range.
A road triple and a Rohloff gives around a 8x gear range.
A SA hub plus all the works gives around a 10x gear range.
A Slumpf SD with twin chainrings and a Rohloff gives around a 13x gear range.
A Slumpf HSD with twin chainrings and a Rohloff gives around a 18x gear range.

Guess which one I picked ....
All I can say is "it's fun to pedal slowly downhill at 40 mph" ......

Luck ..........

[slowster]

When choosing the sprocket and chainring combination with a Rohloff, something to consider is what 11th gear will be. 11th gear is 1:1 drive, and the most efficient of the 14 gears, so ideally it should be your most used gear. If you know what gear you use most with your current derailleur gears, you can use the link I gave above to work out what sprocket and chainring combination(s) would give the same gear in the 11th gear position of a Rohloff.

It is not essential to have gear 11 as your most used gear, and for various reasons it is not the most used gear on my own bike, but it is preferable.

[Psamathe]

Many thanks all.

I'll reflect further but very reassuring to know I'm not limited to the configuration/gear range ICE provide. I still don't like the slumpfh stuff but it does see there are front derailleur options (which I'm fine with). I dislike the Microshift bar end shifters but it's the rear indexed one that is rubbish, the friction front one has been OK.

I'm definitely in a reflect, think, etc. so probably wouldn't be actually doing until early spring.

Thanks all.
Ian