Just trying to sort things out in my mind as I get confused very easily 🙂
I currently have a CdF with Sora (9 speed) set up with 50/34 front and 11-32 rear. If I wanted to keep it as a double and lower the gearing for low speed pootletouring I have two options - either change the front or rear (or possibly both).
If I wanted to change the front only - could I just put on a MTB crankset (e.g Deore 40/28 or 38/40) and it should work fine with my existing Sora STIs and Sora front mech. Does it matter if it says the crankset is for 10 speed ? (I'm presumimg not).
If I wanted to change the rear set up, I believe my existing 32T is the largest I can fit with a Sora rear mech? (has anyone tried larger?) so I would have to change to a deore 9 spd rear mech if ! wanted 11-36. Again would this work fine with the Sora 9 spd STI. I'm fairly certain this is okay 🙂
Have a play with [url= http://sheldonbrown.com/gears/ ]this[/url]... 34-32 is a pretty low gear 🙂
I spent alot of time thinking about this as I might get a CDF 10 next year
I'll tell you what I know and add dome questions
As far as I can see the easiest is a 36 tooth rear block and new rear mech. I'm sure the STI will work
There are potential problems with the front. I think you do need a 9 speed
double and they are hard to find in say Deore unless its say 22 - 36 which sounds a bit spinney even for me
The second problem is I don't know if the front mech will work with rings of that size
Lets hope some one else can shed some light on this
Lazy bike - No, it's not that low. No gears are too low for touring. Trust me.
I can see what the OP is after, I'd go as low as possible, personally, at the sacrifice of top speed.
Jerry, I'd change to the Deore mech (m592 is it? There's a specific one for the 36t cassette) and get the lower geared of the two crank sets you've listed. Probably need a Deere front mech as well, but give it a go with the one you've got first. No reason it shouldn't all work fine. 🙂
34-32 at 50rpm is just over 4mph..I know op said pootletouring.. 🙂
Stick a triple on if you genuinely want to tour. As PeterPoddy said no gears are too low for real touring. I run an SLX triple with 26/36/48 rings.
I'm running a CDF with a triple up front 22-32-42 and then a 12-36 on the rear. Bike is used for bike packing in Wales both on and off road. Believe me the extra low gears are really useful when it's loaded at 60lb for grinding up the Welsh mountain tracks.
My bad was assuming road riding...
sod that.. 🙂Believe me the extra low gears are really useful when it's loaded at 60lb for grinding up the Welsh mountain tracks.
34-32 at 50rpm is just over 4mph..I know op said pootletouring.
Which is true. Maybe a shade over.
I suppose I'm an obstinate git and probably like to keep my cadence at 80 or so
I get confused very easily
Don't be so hard on yourself! 😀
There is a difference in chain line between road double (43.5mm) and mtb triple (47.5mm) cranksets, you may think you can get around this by using an mtb front mech but they need a different cable pull so if you try your road sti shifters then you'll run into problems, it can be made to work but it's very picky and will just end up causing you grief with chain rub in the middle of nowhere when you're fully laden down with 20kg of luggage and trying to climb a 1:4 gradient in the pissing rain as a gale howls down on you.
Your best option is to buy a road triple crankset and a single triple sti shifter and possibly front mech if yours does not have the correct range.
You and Bookwyse should get a job with the CTT...you're really selling this touring lark! 🙂with chain rub in the middle of nowhere when you're fully laden down with 20kg of luggage and trying to climb a 1:4 gradient in the pissing rain as a gale howls down on you.
34-32 at 50rpm is just over 4mph..I know op said pootletouring..
I'm quite often down to nearly half that speed. But then I tow a trailer.
I run 22-32-44 with 11-34 cassette on a 26in bike. Full MTB 9 speed gearing. Perfect. 🙂
OP is a whippet like athlete build, PP, unlike you and I!
My triple slx runs withe tiagra sti units and a tiagra front mech. No dramas with chain rub here. I thought most traditional touring bikes ran this set up without any issue?
There is a difference in chain line between road double (43.5mm) and mtb triple (47.5mm) cranksets, you may think you can get around this by using an mtb front mech but they need a different cable pull so if you try your road sti shifters then you'll run into problems
I thought with 9 speed it was all compatible. Like johnyboy666 says there plenty of touring bikes that do this. Thorn cyles for example
Here is another example?
[img] 
[/img]
Thanks for the replies chaps 🙂
Just to clarify - I actually do have a triple. I built up a Kaffenback 2 over the summer with mainly 9spd sora (STIs, front and rear mechs and 11-32 cassette ) coupled to a stronglight 28/38/48 crankset which I will probably use for light touring. At the moment it's not quite set up right as I've got some chain rub in the middle ring which I'm hoping to fettle out. It disappears when I put a bit of sideways pressure on the big lever, which I think means I need a bit more cable tension (i.e. moving the lever moves the mech outboard a tadge and the noise disappears). Maybe I should give up on STIs and use bar end friction levers 🙂
Stronglight also do the crankset in 46/34/24 so I could lower the gearing more if I felt the need (hopefully the front mech would work with the low tooth count of the smaller ring).
The original post was whether I could make a lower geared pootletouring CdF with a double (more out of curiosity unless it was really simple and cheap).
CFH - I might possibly be more svelte than you but I bet I'm older with worse posture both on and off a bike 🙂 Someone once described their posture as that of a wok smuggler and I expect my back looks a lot like that 🙂
Mr Poddy - I'm suprised you didn't suggest that I buy a Tour de Fer. 🙂 I'd quite like to see one of those in the flesh.
I know what you look like. We've met. 😀
jerrys
As I'm looking into getting some sort of versatile road bike. Howl about a quick summary of the pros and cons of the CDA verses Kaffenback
Cap'n - in which case you must be Charlie and I claim my prize?
a stronglight 28/38/48 crankset which I will probably use for light touring. At the moment it's not quite set up right as I've got some chain rub in the middle ring which I'm hoping to fettle out.
this *might* be to do with the 10T difference between middle and top. some mechs can be fussy on the middle top jump.
info here http://www.peterwhitecycles.com/chainrings.asp but be cautios - i think some of it refers to previous incarnations of DA/ultegra.
Thomthumb - thanks for the link. Don't think this is the issue though as my set up is the same as what Spa use on their tourer.
ampthill - it would be a comparison between the Kaff and the CdF (not CDA). I'm probably not to person to ask though because before last year I hadn't ridden any bike for about 8 years and the last drop bar bike I rode was in the late 70's and it only had 5 gears. Consequently any bike feels good compared to that !
jerrys oh the irony
My road bike has a 5 speed screw on block. The frame was an 18 birthday present 30 years ago! But it just feels way to cramped now