Rode a fat bike for the first time at Coed-Y-Brenin last week and am smitten!

So much so the I’ve taken advantage of some offers on On-Ones web-site and am now awaiting delivery of a Fatty Trail, forks and wheels.

Intent is to build it up from the spares bin. I’ve plenty of gears, brakes, bars and so on but there are a few bits I’ll need.

I’ve a set of square taper cranks but no BB – does anyone know what spindle length is required? Can’t find anything on O-O website though I’ll drop them an email.

And then tyres? Jumbo Jims seem pretty ubiquitous. O-O Floaters seem to get good comments and are a fair bit cheaper for a pair. Which others to consider? Price is important as I’m trying to keep the budget for this under control!

Any advice welcome

Al

JJs are really good til it gets muddy- I think of them as a fat Nobby Nic basically. The 4.8 is a bit more capable but I’m not sure if that’ll fit in your bike?

Thanks Northwind. Yep 4.8s too big

I run NNs on my regular bike and am happy enough with them, so JJs would seem an obvious choice. How do the floaters compare, £40 saving pays for the headset!

The floaters are pretty awesome. They’re a bit baggy on the oo rims & I can’t decide if it’s them or the rims that are to blame.

I was happy with Floaters until I tried Bontrager Hodags.
If I hadn’t tried different tyres I guess I would still be happy.
All the tyres I’ve tried on my OO rims have been loose.

JJ’s are pretty good all rounders for normal trail riding and trail centres, they’re also pretty good on sand and are very light & roll fast(for a fattie)

I’m happy with my floaters.
They were very loose on the on one rims, but are incredibly tight on my ican rims.

So seems most are happy with JJs or Floaters. Reckon I’ll save a few quid and go with the floaters

Anyone any idea on BB spindle length required?

I have some used Floaters which are yours for £20 in a poppy box and if you arrange collection.
Can send pictures if you like.

I’m new to this also and with Floaters on my Dune. Due to not being tubeless my first trip out was very pingy and slippy (it was wet) at 12psi. Tubeless now and down to 8psi and it feels much better (dry though this time).
All in all its the rigid fork that is taking some getting used to, the bike just rides like a bike.
But, and maybe I’ve just been unlucky, it seems to collect dog shit wherever I go..

Thanks Zippykona – that’s too good an offer to turn down. I’ll drop you an email. Whereabouts are you?

And with 1×10 I’ve had to drop to a 30t up front, 11_42 cassette.

I’m in Surrey.

zippykona – emails sent

If you read the spec sheet for the trail it states 100mm BB size – make of this what you will! Welcome to the club btw 😀

Yep – I got the BB shell is 100mm. What I’m trying to find out is the spindle length required to get the right chainline. I’ve seen versions from 142 – 164 mm

flashinthepan – Member
Yep – I got the BB shell is 100mm. What I’m trying to find out is the spindle length required to get the right chainline. I’ve seen versions from 142 – 164 mm

Ah, that I couldn’t tell you – sorry!

Spindle length is dependant on the cranks. If you can find out the length required for a regular bb shell you should be able to to work it out.

Just thought I’d post up my impressions of the fat bike ride at C-Y-B

I was in Snowdonia on a family holiday, we were at C-Y-B for a quiet walk.

My lads (teenagers) saw a Trek Farley for hire for the day. It didn’t take much persuasion for me to take it out.

We did the blue (Minotaur) trail as it consists of a few loops off a main fire-road (back to the visitor centre) which meant we could take turns on the bike and pick up the walking group on the fire-road. I guess we all had about 2 hours actually riding it. For those that don’t know (I didn’t) the blue at C-Y-B is pretty tame and has a good solid surface right through. No major features, but it rolls up and down, lots of rollers and a few switchbacks

Anyhow, how did it ride? Well, like a bike!

Point it down, even down a small gradient and it picks up speed and the massive tyres give amazing confidence.

I didn’t miss a suspension fork at all – plenty of squish and cushioning from that tyre.

Cornering requires a different technique as you have to consciously turn the bars rather than leaning. Once you get this it’s surprisingly nimble. There was no tendency for the for the front wheel to ‘tuck in’ on the uphill switchbacks (unlike my Anthem).

It does need more effort to accelerate out of turn and uphill, so will reward riders who are able to carry their speed through features and corners.

And even though it wasn’t particularly muddy that big rear tyre did throw up an awful lot of crap -be prepared to get mucky!

Overall I loved it and it offers a different experience. I wouldn’t spend mega bucks on one, but then again I have just bought a frame forks and wheels so who knows where the upgrade itch will take me.

YoKaiser – Yes, makes sense.

The BB I have for the sq taper cranks is 73 x 122. So I’d need 100 x 149?

I’ve seen a 100 x 149.5 so maybe this?

4.8 JJs must be pretty close to fitting, at least at the front (I’m presuming you bought a Carbon Fatty fork). If it is marginal, you could always use http://nextdaytyres.co.uk/details.aspx/SCHWALBE-TREAD-CUTTER/1960 to trim the knobs a little.

Or try and source the new 4.4″ JJs. 😉

jumbo jims
good points
light weight .
rool ok on tarmac

bad points
no grip on foots and rocks
no much grip on grass and mud
wear out quick on roads .

Cornering requires a different technique as you have to consciously turn the bars rather than leaning.

Go faster – you can then counter steer like on a motorbike. 😀

Enjoy the new bike. Fat bikes are fun because bikes are fun.

From a personal point of view I’d recommend a tyre pressure gauge, something like a topeak Smarthead if you want digital or an accu gauge for analogue. It makes playing around with psi and finding your sweet spot much easier.

Here is great for info and so is the UK fat bike forum.

I came across this link about fat tyre pressures – http://lacemine29.blogspot.com/2016/01/fat-tire-pressures-for-snow.html Probably not too far out as a starting point, adjust by 0.5psi until you are happy.

They are definitely different but I went from 29er to semi-fat to fat so it didn’t seem quite so “out there” in the way that some people describe, presumably those who missed out the semi-fat step.

Some have said that getting on to the UK fat bike forum can take a while but for me it was about 48hrs from sending the request to registering. Could just depend on when the moderator gets round to things.

I’ve sent 4/5 requests to the Fat forum since getting the Dune, nothing

I tried the 1psi for ever 10kg of kitted up rider. It gave me the perfect base point.

Keep persisting with the UK Forum. It’s been a great place for helpful information IME.

Woohoo, postie had presents today!

Fatty Trail frame in grey / orange
Fatty carbon forks in black / orange
Emmental Rims on El Guappo hubs

For some reason On One have generously included rim ‘tape’ for 4 wheels.

Nice looking frame, lighter than I expected. Forks too, they seem incredibly light but probably just because I’m used to a suspension fork.

Slightly disappointed with the headtube arrangement. It’s set up for an integrated headset. Nothing wrong with them, just I’ve got plenty of headset bits and pieces but nothing that will fit. Anyway ordered (from CRC) a Cane Creek 40 IS42/28.6 – IS52/30 which seemed to be pretty much all I could find.

Unfortunately I’ll not get the frame till Christmas as it’s from my Mrs, but at least that gives me a bit of breathing room to try to source (cheaply!) a few bits I need – mainly a crankset

Did you buy a bung as well for the carbon fork, namely http://www.planetx.co.uk/i/q/FSPXFCENT/planet-x-carbon-fork-bung-(team-alu-carbon-fatty-fork) {which has now gone up another £5 since the weekend to £15, I got mine for £5 mid summer}

Unless they changed the design, the outboard side o the freehub isn’t sealed very well. Take the cassette lockring off, and smear some grease in there!

Get a digital or low pressure (30 psi max) gauge as suggested. 1 psi is a huge difference. I run 8 psi front, 9 rear IIRC.

As goat says, you need the bung for the carbon fork, a star nut will not work.

I have a Fatty from the first batch (nearly 4 years ago!) and love it!

BB – I run middleburn square taper on my fatty trail. Like you was unsure on chain line and BB size, my best guess was 145mm needed. Ridewill sold 142 or 147 and nothing in between so bought both. 142 is what I’ve gone with chain line fine I’m running 1×10. Clearance to Chainstays fine, clearance to tyre is OK albeit only just (floater).

bri-72 – many thanks

The cranks I’m planning to use (hopefully only briefly) are OE Suntours. BB they came with was 124.5mm for use on a 70mm BB shell. Simple maths teals me I need a 154.5 spindle to use with a 100mm shell. Sound right?

How was your experience of ordering from Ridewill? I’m always tentative about ordering from abroad

Hmmmm.
For cranks I have gone with a simpler set of info..
100mm shell ( it’s the usual ht2 bearings but the connecting plastic tube is longer)
Rear hub spacing as this defines the chain line…

So
“I need a set of cranks for a fatbike, 100mm Bb shell and 190 rear spacing” *

*your rear spacing may differ, mine is 190mm

70mm sounds odd BB shells usually 68 or 73 on ‘normal’ bikes, but I essentially did the same calc as you added 32 (100-68) to the stated spindle size for my chainset. If you’re running 1×10 I don’t think you need to be exact, my example above shows I’ve gone for a bb 3mm narrower than should be and has gone fine.

Ridewill used a couple of times and been just fine, from memory any price shown always has 20% vat added as well s shipping, so pricing not always as cheap as first appears. Suspect brexit and exchange rates won’t have helped pricing.

If you take a look at the One Up website there is an interesting article on correct chainline. I found this usefull for converting my Voodoo Wazoo to 1x. Using the standard cranks I have to mount my chainring where the original granny ring was.