chain ring for rohloff

mazza

i orderd my thorn raven yesterday and im not sure about the chain ring ive ordered 44 tooth in not sure weather its too high a gear ratio and the low gears will not be low enough. i can change my order so any advice will be helpfull.

Unknown

With Thorn you have a 100 day money back guarantee.

what are the ratios

My 11th gear is 68nch and I find that OK/

george

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mazza

i ordered i yesterday they havent made it up yet im not reaaly up on gear ratios but on the order form it says 44t thorn 110mm 5am reversable single ring black

daviddd

Well I chose an ultra-low Rohloff ratio of 36x16 - roughly an 18" gear minimum. I suffered a little in the Alps with a deralleur 30x28 which is a good bit higher, and wanted to make sure this wouldn't happen in my forthcoming Oz circuit. I'll be hauling 45kg with the Raven's weight included and plan to go offroad for days at a time. I tested the Raven out on a 1 in 3 track and sailed up in bottom gear lol.
I also suffer from weak foot muscles due to spinal injury so a very low gear is much easier for me, so maybe this is not good advice for you mazza.. With the 36x16 I can still pedal up to 30mph @ cadence of 90 in top and that's quite enough.

Alpine Tour July 2006:
http://www.crazyguyonabike.com/doc/?o=l ... =1914&v=9d
Forthcoming lap of Australia:http://www.davidddinoz.blogspot.com/

mazza

i think i went up same hill on 40-16 and i got up it all right so idecided to go for the higher ratio but im not sure how much difernce it will make

julk

As has been said the 100 day guarantee covers money back, but Thorn will also make changes which you need to the bike to get the best fit for you and your cycling style - like getting the chainring size to suit your intended riding.

I would say 44 is at the fitter end of the cycling scale with a thorn raven.
I got a 38x16 myself with a view to loaded pannier touring in some hilly areas and find it ok.

It is easiest to move from a larger to a smaller chainring since you also need to shorten the chain at the same time.
Going from a smaller to larger chainring you will need to add in some spare chain.

I hope this helps.

geocycle

I went for a 40 which is about right for me. As well as getting the extremes right you should think about getting 11th (the direct drive) as your cruising gear. With a 44 you might find you use the slightly noisy 6th and 7th more than had you selected a smaller chain ring. Best is to try it, I'm sure SJS will swap it if it's not right.

mazza

thanks for that info i will ring them back on monday and ask the guys there to may ne change it as i first chose the 38x16 with help from andrew the sales person

ankev1

Geocycle,

if you regard the direct 11th as the cruising gear, how much do you expect to be using 13th and 14th? I find that most of the time on the flat, I'm in the range of 10-12th. Do you regard 13th & 14th as essentially downhill gears? I hardly ever use them. BTW my bike's a recumbent if that makes any difference.

geocycle

Ankev1, I also tend to use 10-12th most of the time, I use 13th and 14th for downhills, tailwinds, or if I've a train to catch! I find 11th with 42 x 16 suits my normal speed and cadence. This will be different for each rider, I am very uncompetitive and tour for the sake of the journey.

pw2389

I have a 38x16 combination. Usually this is fine but last month in Scotland I found that fully laden (2 front panniers, 2 rear panniers, barbag, tent on rack) that I wasn't able to get up quite a few gradients (that said some were 25%) and had to walk up :-( Mind you, I'm not fit and my legs aren't strong so could have done with more preparatory training!

So, a 44 ring sounds pretty demanding to me but maybe fine for your legs.

daviddd

What should be remembered is that leg / foot injuries are more likely to happen when straining on the pedals - pulling heavy weights up steep hills for example - hence my choice of 36 x 16.
It's actually an 'illegal' combination acc to Rohloff, but only because it 'might' fail the test of forces on the gearbox applied by 2 supreme athletes on a tandem - which is the cos. exacting (and somewhat overbaked) yardstick.
One can always work on increasing cadence - as I say I can cruise at 28mph or so without 'spinning out', which is fast enough fully laden. I probably spend most time in 11th or 12th gear.

Alpine Tour July 2006:
http://www.crazyguyonabike.com/doc/?o=l ... =1914&v=9d
Forthcoming lap of Australia:http://www.davidddinoz.blogspot.com/

strat

Iuse a 42 x 16 and find it just right, I live in the North Downs area which has quite a few short sharp hills and get up ok. I do not carry much gear though.

Michael Falk

I've been touring with a 38X17. For the Alps I don't think I could've had a too low a gear, steep & long hills & I try to avoid being in agony. I ride at about 90 rpm & on the flats with a big tailwind I cruise along in 12th or 13th. On a decent downhill I wouldn't mind having a higher gear available but while touring I'm happy to coast.

I'd rather have the low gear insurance for steep hills than the luxury of a high gear for those fast cycling times when I could just be coasting, resting & enjoying the scenery.

Michael

daviddd

Michael Falk wrote:

I've been touring with a 38X17. For the Alps I don't think I could've had a too low a gear, steep & long hills & I try to avoid being in agony. I ride at about 90 rpm & on the flats with a big tailwind I cruise along in 12th or 13th. On a decent downhill I wouldn't mind having a higher gear available but while touring I'm happy to coast.

I'd rather have the low gear insurance for steep hills than the luxury of a high gear for those fast cycling times when I could just be coasting, resting & enjoying the scenery.

Michael

absolutely right....