Alfine gearing and chain choices for a Fat Bike?

I want to build my first Fat Bike with an Alfine hub. I’ve only had a quick spin on one so am not certain of what sprocket-ring combination to go for.

The crank set is currently 22 32 44. I’m after a gearing range which will be best suited for a spinny pedalling. There are a couple of rear sprocket options 18T or 20T. Will I need a wider chain ring? What chain should I use?

I want to use the bike for some bike packing in the hills and for coastal riding.

Can anyone suggest a sensible gearing combination?

What low % high gear do you want? Is it an 8 or 11 hub – they have different ranges?

Once you’ve answered these it will be easy to work out what you need. 3/32 chain will work fine.

IIRC druidscotroutes had this set up.

Al, it’s an eight speed Alfine. I’d rather maximise the climbing potential of low gearing that have a tall gear for top speed.

wow – that will be a heavy wheel!

I have an alfine-8 on my ‘odd do it all bike’ thingy – 700c wheels.
I’ve put a 20th rear sprocket, paired with a 42th ring. The 18th that was on the rear was just too tall to pull the trailer/camping gear when fully loaded.
Of course, if you are building from the ground up, then just use whatever the alfine comes with, and buy a front chainring to suit (SS chainring, unramped etc)

DrP

Why not run just a single 32T up front and then a 22T on the back. then you wont have to use a nasty chain tensioner.

I run 32 x 21 and have very nearly as low a gear as my double chainring conventional bike (22T granny)…… and I haven’t run out of top end gears yet

I had an Alfine 8 with 32:20 on my Pugsley which got me up most things, only having to get off and push in deep snow or very slippery mud. If you want it spinny I’d be inclined to go 32:22 or even 30:22 if you can get a chainring. I was looking for more of a compromise between spinny and cruising along so kept a ‘longer’ gear.

Also depends on your fitness and the terrain you’ll be riding on

Shimano have a “lowest recommended” ratio IIRC – work from that.

ndthornton – Member
wow – that will be a heavy wheel

Not as much as you might think.

I’ve got 32 front and 22 (i think) rear – works great on my Pugsley

Shimano have a “lowest recommended” ratio IIRC – work from that.

there are 2 schools of thought on that one 🙂

9:Zero:7 with a NuVinci and 42:28, spins out at 20-25km/hr

No chain.

Speak to Sideways Tim.. he’s pretty switched on with these kinda things..

Thanks folks.

Will an Alfine only use the sprockets listed by Shimano?

I will make up an order later but so far I’m thinking of going with…

On one list only 18T or 20T Sprockets.

http://www.on-one.co.uk/i/q/SKSHALF/shimano-alfine-sprocket-with-chain-guide

Chainring I’m thinking one of these with 32T

http://www.on-one.co.uk/i/q/CROOSS/on-one-stainless-chainring

Chain

http://www.on-one.co.uk/i/q/CHKM710SL/kmc-k710sl-1-8-inch-chain

With an 18t on the alfine the output range is equivalent to a 11-32 cassette -ish. So stick a 20t on and the output range drops a %age (equivalent to the difference in ratio of the previous gearing).

Any shimano or sturmey (apparently) hub gear sprocket will fit, tho you might need to watch the cable/shoft arm on the hub as with bigger sprockets apparently it can foul. On-one are not the cheapest tho. Also, i think 8 speed chains work (anyone?) and tend to be cheaper than 1/8 for some reason.

Nexus sprockets fit also and there is a much wider range
20, 21, 22, 23

Quick reply.. last winter I ran my 11 speed Alfine with a double ring up front and using the Alfine chain tensioner. I’ve completly ignored Shimanos gearing recommendation (which only applies to the 11 speed in any case) and had no issues at all. I didn’t get around to refitting it this winter. It’s a pretty hefty wheel right enough and that makes it a bit of a drag on certain terrain (which is why I run 2×9 the rest of the year.

The Nexus sprockets also fit, so you have more choice.

Use the gearing calculator on Sheldons site if you want to play around with numbers.

Fatbikes definitely play well with low gearing – all that traction. However, there are a few stories of knackered Alfines once they’ve been heavily used in coastal conditions

However, there are a few stories of knackered Alfines once they’ve been heavily used in coastal conditions

I spoke to Coastkid about shoreline Alfine durability. He used as part bike part submarine, so I’m not wholly surprised at its limited life expectancy.

I like the simplicity of the straight chainline, low maintenance and reduced chances of tearing a mech off through heather.

Depends on your fitness I guess.

I’ve 2x alfines, a Pompino with 44:20 which would be way too high for you and a 456 with 32:20 which is brilliant. I’d suggest you go 32:22 as a start, I’m 220lb and get up 99% of everything I do with my 3×9.

The benefit to nexus sprockets which hasn’t been mentioned is that unlike the Alfine, they are off-set – so brilliant if your chainline is a little off. I’m still using a whipperman? Anti rust SS chain thing for the last 5.5 years, in fact none of my 2 alfine drivechains has been changed.

I understand the risk with heather but short cage shadow mechs are tucked pretty much out of the way.

Quick bump for a singlespeed chain recommendation.

There are few shit chains and no amazing ones Pete.

KMC Z610HX is what I use on both my singlespeed and my Alfine bike.

There are few shit chains and no amazing ones Pete.

Hit me with an OK non shit one name.

Try sjs for the full range of alfine, nexus and sturmey archer sprockets. The sa ones need a track chain iirc.

mcmoonter – Member 
There are few shit chains and no amazing ones Pete.
Hit me with an OK non shit one name.

The one that I use – KMC. Anything but a SRAM PC-1, that is a shit chain IME.

Try sjs for the full range of alfine

Thanks for the tip, I ended up getting everything from them.

Awaits the postman.

Awaits the postman 🙂

I need an 8spd Alfine Pug again, ace for long grass green lanes in summer…
And a SS pug for simplicity…
And a Steampunk ratrod pub pug for giggles…

😀

Mcmoonter, I will be selling an 8 speed Alfine and shifter on a 26 inch DT swiss rim (in the next week). £50.00 if you are interested. 6 months old
email me steph dot madde at o2 dot co dot uk if interested

Steve

Monkeysfeet – YGM