Muddy builds a fat bike at last. The On-One Fatty with Rockshox Bluto forks.

The origins.

About three years ago I was on Cannock Chase in Staffordshire. Saw a group of riders, and amongst them were three bikes with massive tyres. They looked utterly pointless and hard work. The riders on those bikes looked to be having the most fun out of the group.

I had to have one. Yet with four bikes, no snow where I live, and only working part time, I couldn't justify it. Well until On-One had a sale on, and I managed to get a Fatty for £149.

The build.

Silly me. Made the assumption that some bits from my other bikes would fit. Not a chance. Rear hub, 170mm; Front hub, 150mm. Even the front mech needed an adaptor. In short all I could use from my stash was a saddle, handlebars, seatpost and pedals. Not much is it?

I've built up lots of bikes from the frame up, so understand builds. This one involved some slight head scratching, and sourcing of components from all over the place, yet it all went together in a logical fashion and I quite enjoyed it all. Even so it still took me two years, as there was no rush. Ended up as a result with a bike built from a strange mix of bits.

  • Home made front mudguard from a bleach bottle.
  • Used handlebars and stem.
  • $1 bargain bucket items from Decathlon.
  • New transmission from CRC. Went 2x10 in the end. Hills you see.
  • Hand build wheels by a Specialized team mechanic.
  • Rockshox Bluto.
To my eyes it all looks reasonably factory. It weighs 35lb though. Needs to go on a diet.

Sportsman pub at night

It has probably cost around £1,400 to build. On-One are now selling this frame off as a complete build for around £800. So mine is no bargain.

So, how does it ride?

My first outing, a night ride to the Sportsman pub, was a mix of disappointment and joy. I live at the bottom of a hill, so every ride starts with a two mile climb. This bike so does not like roads. It was hard work and I was puffing by the time I got to the top. Then hitting the off-road bridleways we have, the bike did not seem comfortable at all. I'd only put 9psi into the tyres, and they were quite squishy at that. Under braking the front tyre would squirm away as if flat.

If I stopped pedaling, the bike would slow appreciably.

Hmm, not happy. Too much like hard work this.

However it would climb gravel with no loss of traction, and deep, muddy puddles were dispatched with ease. And with gravity on my side, it picked up speed well enough. Also the double top tube configuration meant a happy nesting place for my battery.

After three hours I was knackered. Not a good start was it? The bike wasn't even comfortable; no better than any other of my hard tails.

And my use of old parts bin stuff meant that the carbon handlebars, at 660mm wide, were way too narrow.

The next morning.

You know those trail centre breaks you do? On the third day your arms ache and legs feel like lead? That's how I felt wheeling the bike out the next morning.

Ah well, my bike now best crack on.

That climb was still horrid. When I got to the top though, I was on a mission. My mate PP was at Box Hill and I was due to meet him en route somewhere. Did not want to meet him locally, so I pushed on.

Well now, that's interesting. Instead of the bike slowing, and being draggy, it felt much more alive. So the trick is to keep pushing? OK, game on. Up for that.

Bit of effort, bit of a push, and the bike starts to move. Still not fast, but better than coasting to a stop and starting all over again style of last night.


Those big tyres do find grip. Rocks, mud and sand all disappear under them. Yet the bike would not suit a learner or somebody looking for an easy ride. It takes effort to turn, using a lot of body English. Under braking my bike gives an effect similar to a tank slapper on a motorbike. Sometimes the trail just grabs those tyres, and sweeps left or right on a whim.

In short it is not an easy ride. You have to be on it to get the best out of the bike.

Headley Heath.

By the time 8 miles was up, I was being aggressive with the bike. Lots of un-fine manual inputs, real muscle work to get it to do anything. Doing this everything was fine. 

Bumped into PP just outside of Box Hill, so we did a loop of Headley. Now Headley is, in effect, a beach. Lots of sand, lots of gravel. It has some steep slopes, all covered in sand and rubble. The first one I flew down, really fast. Got to the bottom, PP was way back. 

Waited, he caught up, went off again.

Next slope I flew down, with STRAVA putting me in the top 20%. Waited at the bottom. PP must have a puncture? Nope, he came down asking about those rocks!

Sorry? Rocks?


Found a few muddy slopes that I've never been able to ride before. Bike just clawed my way up on this device. That was a giggle. One big slope near home, that on my other bike I set a KOM on, only went and matched it on this bike, first time out.


Build one of these, and you are not a wilting violet. People literally come up to you and say "what the f*** is that!"


The bike can be fast in the right conditions. Put some effort in to the ride, grab it by the scruff of the neck, and you can keep up with mates, even get ahead some parts. Surprisingly far ahead as well. On my second ride I set three fastest STRAVA times. That takes it out of you though, a real work out. Overall I'd say, and this may well come as no surprise Dear Reader, that it's best suited to low traction, slower conditions. Snow, mud and ice basically. How funny is that? Those short night rides out into the snow? This bike would be like a Ferrari then; on top of it's game. You'd have a laugh.

Of the bikes I built, some were dogs. The downhill only one especially bad. I'm man enough to admit when things have gone wrong, and sell them on. This bike falls into the utterly brilliant category.... In the right conditions. I like it, really do.