Author Topic: Fat bike hubs  (Read 8106 times)

quixoticgeek

  • Mostly Harmless
Fat bike hubs
« on: 25 November, 2018, 10:17:18 pm »

What's the widest sensible tyre size you can run with a 148 OLN hub?

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Fat bike hubs
« Reply #1 on: 25 November, 2018, 11:38:31 pm »
I think that at that width the hub will not limit tyre width as much as the available space between the chainstays will; rim width may also come into it.

Torslanda

  • Professional Gobshite
  • Just a tart for retro kit . . .
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Re: Fat bike hubs
« Reply #2 on: 25 November, 2018, 11:46:07 pm »
148 is generally described as 'boost' axle and (usually) a 12mm bolt thru.

Fat bike is 175(ish?) although charge fit fat 80mm rims to the 'Cooker' with 4"tyres and use a 135mm QR hub and build an asymmetric rear triangle.

Unless the frame is designed for fat or 'plus' tyres you would normallyexpect 2.3/2.4 tyres to be the maximum width to retain a safe margin of mud clearance
VELOMANCER

Well that's the more blunt way of putting it but as usual he's dead right.

quixoticgeek

  • Mostly Harmless
Re: Fat bike hubs
« Reply #3 on: 26 November, 2018, 12:49:10 am »

I should have been clearer. Was thinking of adding a fat bike to my stable, and it would be built from scratch. So was idly wondering about hub spacings, as it seems 148 is the largest Shimano make.

So if the frame is built for what ever size is chosen, with a 148 oln hub, what are the options for max tyre width ?

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

PaulF

  • "World's Scariest Barman"
  • It's only impossible if you stop to think about it
Re: Fat bike hubs
« Reply #4 on: 26 November, 2018, 05:20:13 am »
I’d look beyond Shimano for your hubs; 148 is merely plump. For example I have Hope Fatsno on my fatbike which is 170 at the rear.

Torslanda

  • Professional Gobshite
  • Just a tart for retro kit . . .
    • John's Bikes
Re: Fat bike hubs
« Reply #5 on: 26 November, 2018, 08:54:41 am »
OK. Have a look at the fatbikes de jour. I think you'll find they are based around 80-100mm rim width and a 4" wide tyre, mostly 26". Front axle spacing is 120(ish) rear 175(ish). Lots of hub manufactureres to choose from.

As mentioned the Charge Cooker uses a 135 rear hub with an asymmetric rear triangle - necessary because the tyre necessitates a 100mm BB shell for the chainline to clear the rear tyre.

VELOMANCER

Well that's the more blunt way of putting it but as usual he's dead right.

PaulF

  • "World's Scariest Barman"
  • It's only impossible if you stop to think about it
Re: Fat bike hubs
« Reply #6 on: 26 November, 2018, 09:43:12 am »
135 rear hubs are what the original fatbike, the Surly Pugsley had as that was what was available at the time. That required an offset rear triangle and wheel to allow the chain to clear the tyre with a 100mm BB. They're a bit of an oddity and most modern fatbikes have a wider hub and symmetrical rear end.

The fork on the Pugsley was similarly offset to allow front and rear wheels to be swapped.

Gus

  • Loosing weight stone by stone
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Re: Fat bike hubs
« Reply #7 on: 26 November, 2018, 07:06:37 pm »
135 rear hubs are what the original fatbike, the Surly Pugsley had as that was what was available at the time. That required an offset rear triangle and wheel to allow the chain to clear the tyre with a 100mm BB. They're a bit of an oddity and most modern fatbikes have a wider hub and symmetrical rear end.

The fork on the Pugsley was similarly offset to allow front and rear wheels to be swapped.

That's how my pugsley are. Have swapped fork for a Moonlander Offset fork and 4" tures. men

Re: Fat bike hubs
« Reply #8 on: 27 November, 2018, 10:10:22 am »
Aside from the interim 135mm "standard" which was really just to allow component manufacturers to catch up you have two main rear hub standards based around 175mm and 190mm. The wider width is to allow full 5" tyres but you need cranks with a wider Q-factor to clear them. Generally 80mm rims are fine for most purposes unless you are riding a lot on soft snow/sand when 100mm rims and 5" tyres give you the maximum flotation.

My bike came with Industry Nine hubs - the previous owner had had a falling out with Hope. There's also DT Swiss and Halo who do fat specific hubs, haven't seen one from Chris King though there were rumours that they were making one.

Incidentally the UK fat bike forum has been resurrected, it's at fat-bike.co.uk. Hopefully it will be longer lived than the old one.

quixoticgeek

  • Mostly Harmless
Re: Fat bike hubs
« Reply #9 on: 27 November, 2018, 10:15:06 am »
Aside from the interim 135mm "standard" which was really just to allow component manufacturers to catch up you have two main rear hub standards based around 175mm and 190mm. The wider width is to allow full 5" tyres but you need cranks with a wider Q-factor to clear them. Generally 80mm rims are fine for most purposes unless you are riding a lot on soft snow/sand when 100mm rims and 5" tyres give you the maximum flotation.

My bike came with Industry Nine hubs - the previous owner had had a falling out with Hope. There's also DT Swiss and Halo who do fat specific hubs, haven't seen one from Chris King though there were rumours that they were making one.

Incidentally the UK fat bike forum has been resurrected, it's at fat-bike.co.uk. Hopefully it will be longer lived than the old one.

I'm not a fan of hope hubs, they are waaaaay too loud (even the newer shimano hubs are a bit loud to my tastes). What are Industry nine and Dt swiss like?

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Fat bike hubs
« Reply #10 on: 27 November, 2018, 12:43:50 pm »
I'll admit I'm a Hope fan (not all their stuff). Industry Nine are similar to Hope as regards noise, never come across anyone on any type of bike using DT Swiss so no idea about them. Those that do say they use them like them though that may be them justifying the price ;D

Industry Nine (and to a lesser extent Hope) are field serviceable. You can quieten, but not silence, Hope Hubs by removing the freehub and adding more grease.