For reasons diverse, I’ve ’29er’d’ the front of my fat-bike. This morning was spent building the wheel, and this afternoon testing it.
It works quite nicely for the more rocky bits – especially with drop-offs aplenty (something that the unsophisticated ‘squish’ that a fat front tyre doesn’t do beyond a certain speed). As a set-up it does ‘plough’ into soft-deep pea gravel unless you’re careful, the difference from a standard ‘thin-thin’ mountain bike being that the fat-rear allows you to rescue yourself. And once jumps get beyond a certain height, the lack of the ‘proper’ rear-squish provided by a dual-suss bike is noticeable.
Summary – A good compromise that warrants lots more attention…
For the technically minded (geeks unite!):
Fork – 2012 RockShox Reba DualAir RLT 29 100mm. (and yes, I will cut the steerer – eventually)
Wheel – Hope Pro2 Evo QR 32H hub with Velocity P35 700c rim, DT Comp spokes and brass nipples. Maxxis Ardent 29×2.4″ tyre (tubed at the moment, though I may try tubeless at some point). 160mm disc rotor, though once I get my hands on the correct adaptor, it will be 183mm as on the fat-front wheel.
How long I’ll hang onto both the fork and the wheel once Sarah gets her ‘one-frame-to-rule-them-all’ will be interesting to watch ;-)
bicyclenomad 
Now all you need is a Rohloff hub with a P35 29er wheel. :-) Do you notice the wider Q factor of the fatbike? It seems to be an issue for some people but not others. I predict both you and Sarah will have 29er wheels for your respective fatbikes eventually.
Gary – I’m likely to get one of the Surly Rabbit Hole rims when they’re available without a Krampus attached – whether I build it SingleSpeed or on a Rohloff is dependent on being able to justify a second Rohloff… I also quite like the fat-tail thing so may well ‘stick’ at that!
I don’t actually notice the Q factor at all – it actually feels more stable and controlled – thought that’s difficult to separate from the 26er vs 29er (or near enough) experience. The ‘fat-tail’ is more like the full-fat with more front squish and thinner tyres than the dual-squish 26er if you know what I mean. It allows me to plough through rock-gardens with less thought and more directness than the full-fat. Guess it’s a lazy mind option :-)
I guess I hadn’t thought of that one. Looks fun.
Does is steer a little lighter than fat tire at low pressure? Less of that weird feeling when you’ve guess wrong and taken out too much air?
Most people start with a 29er and go for fat-front with a fork swap.
For me, I’d noticed that with rock-gardens and drop-offs that weren’t ‘jumpable’ – that fat-front was slowing things down. I could take a different line, but was losing some of the fun. Hence the choice of suspension fork and relatively full-volume 29er wheel/tyre.
The steering is lighter – especially on pavement where a low-pressure front fat-wheel is most noticeable. Unless I’m on pavement, the time I usually notice I’ve taken out too much air is when I try to corner too fast (and get the ‘squirm’) or ride too fast through rock patches and bottom out on the rim; rather than steering as such.
Tom
What the !!?? Clearly I need to get home (-; Gary: my fat bike if I ever get around to it has always been intended to have a set of 29er wheels as well as fat wheels. I don’t think I’ll be copying the fat tail look however….
It doesn’t look half as silly (see what I did there?) as I thought it might. Well done, Tom! Always the innovator!
Scott
Out of curiosity, is Sarah’s bike expected to be built 135mm-offset? Tom, with all the recent considerations of things, would you change any specs on the next custom fat-build?
Nicholas
Sarah’s will be symmetrical 135. Given her light weight she likely won’t need more than HuDus or Nates on MargeLites when going ‘fat’ with an internally geared hub.
From mine, I’m still uncertain whether I would have gone symmetrical, as I wanted to be able run wider rims – that would be my only temptation
BTW, nice looking frame bag! I see you have a divider ‘half’ way up. :-))
I did this a year ago by mistake. I was goofing around in the shed with various bike bits and found I fitted a kona p2 29er fork with a hoped 29er wheel onto the front of my Pugsley. I found the handling at speed on pavement an improvement , it actually went round corners like a real bike. I reckon shocks would be even better. I should have taken taken some pics, it certainly looked different . I can’t see it being a trend ‘tho but I’ve been wrong many times before. BTW, nice bike.
[…] am definitely the weakest link – and only possibly because my fat-tail is inherently the slowest bike by far. It comes as a relief when the final few kilometres down […]
I have contemplated this combination a few times in the past. Front is where suspension and steering precision is most needed. Fat rear gives traction where it is most needed, and some squish so that a hard tail is workable. Any updates on your impressions on this set up? Seems like it would be good for technical, rocky trails yes?
You have the right of it – technical rocky terrain is why I went this way. Conditions have been very dry and soft recently so I’ve actually been using ‘double-fat’ more – life’s cooling down a bit now, and with some rain, I expect to swap things around again. This ‘Fat Tail’ also makes paved sections better with less rolling resistance and a better steering feel.