I have not been able to find one nor any indication of one and my understanding was that 32/23 was the lowest allowable. My 22/18 is well lower than that. I didn't stand on the pedals tho
Bike Forum
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Alfine Hubs
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Posted 2 years ago #
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i work in a shop and we have an Alfine built into a black 317 as in my previous pic, not the same but another one for sale including shifter fitting kit and cog for £225. if your iunterested let me know.
Posted 2 years ago # -
Someone remind me and I will look into the min/max sprocket size at work in the morning.
Posted 2 years ago # -
Sadly having done the maths I don't think the range is quite big enough for me. This is due to my desire for a lowest gear of 22 30 equivilant.
Oh well its a great concept.....
Posted 2 years ago # -
ampthill - alfine on 32 / 23 gearing give a bottom gear of 22 / 30 equivalent with a top gear of 32 /14 equivalent. according to the fine calculator some chap whose name I forgot gave me.
Posted 2 years ago # -
go look at weight weenies. someone on here weighed their hub at 1.6 kgs
I was curious!
ampthill - alfine on 32 / 23 gearing give a bottom gear of 22 / 30 equivalent with a top gear of 32 /14 equivalent. according to the fine calculator some chap whose name I forgot gave me.
OK, this time I was bored and curious!
I've heard the 32:20 min gear ratio thing loads of times, can anyone point me in the direction of an official Shimano document that sets this lower limit, the only time I've read this is in reviews and on forums. I currently run 32:20 but in the past I've happily stood on the pedals with 32:22.
Can't remember who/where it was, but I spoke to someone about this who had already enquired via Shimano about this... Basically, anything down to 32/20 is deemed as ok, anything lower and don't expect to be able to warranty it if anything goes wrong... If they can of course prove it. I don't think it's a set in stone thing, more of a min. recommendation that they go by, rather than using a min. weight limit. Of course, they could go the other way and say that you are free to use whatever gearing you want, but nobody over 10 stone can ride one...
One guy in the states was running a 26/22 setup on his apparently. At 18 stone and riding big hills all day, he managed to strip the clutches on his, which is the torque related issue that Shimano are warning against. To be fair though, I think (can't be 100% sure) he got it fixed under warranty. But of course he had to send it back, and that's a load of hassle etc.
Think of it more like this... At 18 stone would you run a set of coil sprung forks with the Standard Medium strength Spring, or would you buy the Extra Firm spring before riding it? At 12st I can get away with the medium, and won't kill my forks, but if I were 18st I'm going to exert a lot more force on it. Rockshox isn't saying they wouldn't fix my fork if I ran it undersprung, but you could pretty much guarantee I'd bugger it up in a short space of time if it was that severely undersprung if you get my drift...
So my advice based on that is if you're a big guy, don't expect to be able to gear it down that much... If you're similar weight to myself, you can probably get away with doing what TJ did and running a 22T up front if you so desire...
Sadly having done the maths I don't think the range is quite big enough for me. This is due to my desire for a lowest gear of 22 30 equivilant.
Using a 34/22 on mine gives me an equivalent bottom gear of 22/27... Was worried it'd kill me, but honestly, it's like 1 gear difference on a 9spd cassette... Try it, it'll put hairs on your chest if nothing else!
Does the hub feel good pedalling in a gear. Or is it a bit soggy and ineffiecient feeling?
VERY direct, not at all mushy. I've ridden plenty of freehubs on "normal" hubs before that are a lot less direct and feel mushy in comparison.
Again, anyone else wants the gear calculator spreadsheet, just email me... Email is in my profile...
Posted 2 years ago # -
I normally run single speed 32/18 on my 29er but round these parts are very hilly and you get no rest when your out with a group so i took a punt and bought a built alfine wheel running it the same 32/18 set up.yes you have to back of for it change gear sometimes if under load but it aint that bad. I tend to just keep it in 4th and only use other gears on killer hills or fast road keeping up.
Recommended? yes.
Posted 2 years ago # -
So my advice based on that is if you're a big guy, don't expect to be able to gear it down that much... If you're similar weight to myself, you can probably get away with doing what TJ did and running a 22T up front if you so desire...
surely it's a power rather than a weight issue?
you might be a hefty chap but have weedy legs??Posted 2 years ago # -
It's weight AND power. Lots of power but little weight would be fine and lots of weight but little power ditto. Heavy riders with lots of power will be really bad (that's me then!). Typically though bigger guys will be more powerful though their power to weight ratio will be lower which makes them less good at hill climbing.
Posted 2 years ago # -
surely it's a power rather than a weight issue?
It's a torque issue, not power...
Torque kills gearboxs and clutches (which is what the Alfine is) not Power...
A Big heavy guy is going to exert a lot more toque on the hub than a much smaller guy, simply by standing on the pedals! OK, Lance Armstrong might exert even more torque again still by being a superhuman with an incredibly efficient pedalling technique, but none of us are that I suspect!
Power = Torque x (Rotational) Speed
Remember that!
So Power is kind of irrelevant if the speed is increased. A Big Guy churning the pedals at 50rpm but applying 100Nm of torque is producing the same Power as a small guy spinning the pedals at 100rpm but only applying 50Nm of torque.
The Big Guy is going to kill/wear out things much faster though!
Posted 2 years ago # -
Typically though bigger guys will be more powerful though their power to weight ratio will be lower which makes them less good at hill climbing.
if their less good at getting the power down for hill climbing they're obviously inexperienced riders so it shouldn't affect the hub if you know how to climb???Posted 2 years ago # -
if their less good at getting the power down for hill climbing they're obviously inexperienced riders so it shouldn't affect the hub if you know how to climb???EH?
Climbing ability/efficiency has more to do with Power/Weight ratio, as clubber mentioned, than technique really. For a given climb at least, where we're assuming something quite long and not technical.
And again, as Clubber mentioned, a big guy is likely to have a lower Power/Weight ratio than a smaller guy of similar fitness.
Experience and skill would only come into play on a technical climb.
Posted 2 years ago # -
I have an alfine on my commuter / trainer.
Done about 8-10000 miles on it now, with no serious problems.Its very very good for a high milage bike, and if you can't be fannied with maintenance.
It does distribute a lot of the weight to the rear of the bike - not sure if I would want that on a mountain bike. It is heavy too.
Posted 2 years ago # -
what i'm trying to get across is that surely a "big" rider can ride light with experience.
Posted 2 years ago # -
Reading about a bit the Description on the IO seems to suggests the Alfine hub produces the equivalent of an 11-38t cassette in terms of gearing range, I also found the Alfine group’s own crankset which is apparently available in either 39 or 45 tooth flavours, suggesting shimano haven’t quite gotten their heads away from the higher geared Nexus tow path pootling application with Alfine, despite what a lot of people are using it for…
My guess would be (and it is a guess) that one of the mid range gears (4th or 5th ) is 1:1 so whatever your “input gearing” ratio; 32/20, 32/23, 39/28, 45/30? You will actually be running this gear in the middle of your range with the alfine and your range is basically +/– 3-4 steps this ratio either side, maybe ~20% a step?
I’m currently using a 32/22 chainset with an 11-28t 8speed cassette I was mulling over switching to a 36/22 chainset with an 11-32 cassette to give me a wider gearing range (currently it ranges from ~ 75-20 “Gear inches” with the changes I’m considering I’d get ~ 85-18 Gear inches, and a bit less “ratio replication” assuming I’ve calculated correctly) as it is I spend 95% of my time in the “mid” ring and run out of gears on the flat/road, and use the granny if I’m faced with a nasty climb as the top 4 sprockets are my get out of jail climbing gears, I like having at least a couple of easy gears in reserve, and I could live without a massivly Grr gear but wouldn’t want to be any worse off than my current 11-32 top ratio…
I know you’ll never get the range of a double or triple x8/9 speed but just how far off of producing a similar gearing spead would an Alfine be? In terms of ultimate top and bottom end gearing? I presume if you want a get out of jail climbing gear you have to sacrifice the taller gears and vice-versa, but is it a massive amount?
Should I even be considering the alfine instead of yet another 2x8 setup or am I the “wrong sort” of rider?
Posted 2 years ago # -
An alfine produces the same gear spread as a 11/34 cassette. If used with 32 / 18 gearing the ratios are virtually identical to 32 chainring with an 11/34 cassette Obviously buy altering the ratios you move this up and down the scale. It is equivalent to a 1x9 not 2x9 hence I had to gear right down when I wanted granny gears for the 'puffer.
I believe one of the intermediate gears is 1.1 but strangely it is no direct drive and still goes thru the geartrain.
Ask maverickboy for his gearing calculator - it makes it easy to see.
Posted 2 years ago # -
The 11-34T spread is if you run the 18T sprocket. With a 20T sprocket you get 12-38T.
Posted 2 years ago # -
5th is 1:1
Posted 2 years ago # -
Mr P - that is a bit confusing IMO to put it that way - the gear spread is the same from the hub - you have just moved it up and down the range by altering the overall gearing. It doesn't matter if you alter the overall gearing at the chainring or sprocket.
Posted 2 years ago # -
Ok so if I’ve understood you correctly running an alfine with a 32/20 input ratio gives you a range of 69.3 – 21.9 Gear inches (with a 26” wheel) so quite a spinney range then…
I like the idea of an Alfine Hub but I think I’ll take the cheap option (for now) and just change my 2x8 setup… I’m sure they’ll up it’s range eventually…
Posted 2 years ago # -
cookea - do you want a copy of the calculator for gear ratios for the alfine??
32 / 20 is quite low. I went round GT in 32 /18 and tho I would have liked a lower gear I managed fine.
Posted 2 years ago # -
TJ- yes please
Posted 2 years ago # -
Thats the basic info - maverickboy made an excell spreadsheet that is very clever and has all the various ratios, gear inches and so on - you can change the size of the chainrings and see the effects on the ratios - its very clever but I need an e mail to send it to.
Posted 2 years ago # -
I like the MPH at RPM function of Sheldons calculator.
Posted 2 years ago # -
Ah - I didn't scroll down to the calculator.
Posted 2 years ago # -
It's alright looks like Sheldon has (had) all the info, I can just bang a new sheet on my existing Gear ratio calculator spreadsheet [/nerd] cheers
Posted 2 years ago # -
Ok so if I’ve understood you correctly running an alfine with a 32/20 input ratio gives you a range of 69.3 – 21.9 Gear inches (with a 26” wheel) so quite a spinney range then…
Approximately, yes... Depends on your tyre size though of course.
I like the MPH at RPM function of Sheldons calculator.
Drop me an email, I'll send you my spreadsheet... It's EVEN CLEVERER than Sheldon's calculator as you can input your own desired RPM values rather than just some presets. It even has all the info there for you on ONE PAGE so that you don't have to keep refreshing every time you want to change something, or view a different bit of information (which was what bugged me about Sheldon's site, so I created my own spreadsheet)!
It's alright looks like Sheldon has (had) all the info, I can just bang a new sheet on my existing Gear ratio calculator spreadsheet [/nerd] cheers
Happily send you mine mate... I'm not charging for it... You can just copy and paste any info out of it you want into your own sheet then should you desire... Just drop me an email (in my profile)...
The 11-34T spread is if you run the 18T sprocket. With a 20T sprocket you get 12-38T.
11.1-34.2 and 12.4-38.0 respectively if we're being pedantic!
Reading about a bit the Description on the IO seems to suggests the Alfine hub produces the equivalent of an 11-38t cassette in terms of gearing range
Hmmmm, that's misleading... Where's James from Genesis, he frequents here a lot... He was asking me at one point about being able to host my spreadsheet from their site for those with gearing questions about the Alfine...
what i'm trying to get across is that surely a "big" rider can ride light with experience.
Again, I'll repeat my eariler comment... EH?
How does experience defy the laws of gravity?
Posted 2 years ago # -
James is lurking here somewhere. I will point out the error.
Posted 2 years ago #
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