Update 31st October 2005

My Sugar has been over here now since Feb and so the Inbred is back to single speed mode, Ive also upgraded to a Hope mini 185mm disk on the front. I love it! Its the bike I use most frequently and there is only one of the local rides that Ive not yet attempted on it that Ive done a few times on a geared bike, but next time... Apart from that, I can pretty much ride all the trails I used a geared bike on. Many of the ascents are on bitumen or fire-road so they are OK on the single speed.

Update 29th June 2004

Well, we've moved from flat Western Australia to not so flat Bagneres de Bigorre in the French Pyrenees. I've copped out and put gears on my Inbred, at least while I wait for my sugar to get shipped over from Australia. I used On-One's Gimp gear hanger, works fine with a bit of filing to get the fittings to match the width of the dropouts so that the wheel holds properly. Getting the front mech to work properly hasnt been so easy as there is no cable stop on the seat-tube. However, I have managed use the clamp part from an old front mech as a cable stop by removing everything from the clamp and then drilling a small hole for the cable to go through and boring out the top part of the hole (not all the way through) for the cable housing to sit in. This works well. I think there may be some after-market cable stops available, but not in any of the bike shops in this neck of the woods.
Geared Inbred rear mech. front mech.

Update 20th January 2004
Inbred is still going strong, Ive upgraded the forks to 2003 80mm Marzocchi Marathon S. These forks are great, slightly heavy but the bomb-proof construction and performance are well worth the weight penalty.

September 2003
Had loads of fun riding in various parts of Spain and France over the summer: (More on our trip to Spain)
Mountain biking in La Pedriza regional park 50km north of Madrid
riding in the Sierra Mariola

2002 ON*ONE Inbred single speed frame

Why single speed?

If youíre reading this, you must have at least considered the idea of a single speed bike. Thereís something hard to define about the appeal of a single speed bike, possibly itís the simplicity or the fact that itís a reasonable excuse to get yet another bike, but thereís no denying that, once the bug bites you, thereís no turning back. The Inbred is now the third single speed bike Iíve owned and I wouldnít be without one.

What is the On-One Inbred?

On-one and Inbred logos

Designed in the UK and built in Taiwan, the Inbred is a well designed, good quality, CrMo steel frame at a reasonable price. On-One make several frames including a dirt jumper, BMX and single speed commuter. The Inbred comes in a variety of different guises including a disk specific, eccentric bottom-bracket version and a geared version; if youíre looking for something a little more up-market, itís also available in titanium.


The design of the Inbred reflects its UK heritage - good tyre clearances, forward facing seat-tube slot and guides for an enclosed rear brake cable are features useful in muddy conditions but also good for a bullet-proof and dependable single speed.

Another key feature of these frames is the long top-tube and short stem combination. This design has been followed by several manufacturers over the last three or four years. The overall effect is to maintain the cockpit length (saddle to bar distance) but shift the riderís weight back on the bike. This gives the bike a more stable and confident feel, yet, with slightly adjusted riding technique, nimble handling. Iíve been riding this style of frame for four years and wouldnít go back.

The five-piece rear-triangle is similar to that found on DeKerf frames, giving good torsional and lateral stiffness whilst maintaining some vertical compliance. This means no loss of power with some of the harshness taken out of the trail.

Beefy, horizontal rear dropouts which provide about 1" of horizontal adjustment for the rear wheel, give plenty of scope for running a flip-flop rear hub with up to around a 4 tooth difference in freewheel sizes.

Set up can be anything between low and fast for XC racing and more upright free-ride / single track thrasher but above all, itís a bike to be ridden.

The frame weighs in at 4.75lb. Not super light compared with most aluminium frames, but then that is probably an unfair comparison. CrMo steel frames last indefinitely whereas aluminium frames have a limited lifespan mainly due to material fatigue. My CrMo Marin Team is now over 12 years old and still going strong, getting daily use commuting to and from work.

Finally there are rack/mudguard eyelets if needed and mounts for two water bottles.

On-One Inbred single speed

Bike build

Components were chosen to compliment the frameís durability giving a solid dependable ride at the expense of super-lightness. Final bike weight was respectable, tipping the scales at just over 24lb.

The absence of an expensive drive train allows some scope to spec. higher quality components for the rest of the bike. The King headseat is simply the best, as is the Thompson seatpost. The Surly flip-flop rear hub is a dependable performer at a reasonable price. It gives the option of running two freewheels, though Iíve not used this feature as I prefer to run the shortest possible chain in a 32x16 gearing. A non-shifting front chainring should be used and Blackspire do a nice solid 32t downhill chainring. I stuck with standard 175mm cranks though many single speed riders use 180mm. The bars are reasonably wide 1" XC risers on a short stem, giving quite an upright riding position and plenty of leverage when stomping up hills. Originally I had a 100mm, 10į rise stem, but I swapped this for a 90mm, 25į rise to give a nice upright, cruisy riding position.

Crank detail

Rear dropouts and hub detail

Brakes are Avid 2.0s. As far as rim brakes are concerned, you canít go past Avid: simple, dependable and relatively light. All three of my bikes have Avid brakes and they are way better than the Shimano parallel action V-brakes where the pivots wear out in a couple of seasons. The typically dry conditions in Western Australia donít really warrant disk brakes, though if you lived in wetter and muddier places, this could be worth considering on the front. If you were planning to run disks front and rear, it would be wise to get the disk specific Inbred frame. This frame has vertical dropouts so that the disk can be aligned correctly and the chain tension is adjusted using an eccentric bottom bracket - like on a tandem timing chain.

The ride

Thereís something about the ride on a steel frame thatís hard to pin down; returning to one after four or five years on a aluminium hardtail is like getting home and slipping into your favourite old slippers after a hard day at work - it just feels right. Its comfortable, yet active and responsive.

What makes the Inbred different from many other bikes is the length of the top tube. Itís amazing how much difference an inch makes. However, since I road my first Gary Fisher bike with his Genesis geometry, Iíve been a convert to this "long top-tube, short stem" style of geometry. One of the effects is to shift the body back a little on the bike - inspiring greater stability and confidence when descending. However you also gain greater rear wheel traction when climbing and the short stem greatly improves steering precision. The only slight drawback is that there is a little less weight on the front wheel, so you need to lean a little forward when cornering and take care to pull back on the bars rather than up when climbing - though, since the majority of climbing is done out of the saddle on a single speed, this really isnít an issue.

The bike has a pretty neutral feel, allowing you to chuck it around the single track. High-speed, sweeping corners are a real blast as are technical descents - the longer top-tube giving you plenty of confidence to let it rip.

The reasonably low bike weight and stiff rear-triangle gives good acceleration out of corners, and just concentrating on pedalling and not having to worry about shifting gears will tend to leave your mates on geared bikes in your wake.

32x16 seems the defacto standard gearing for single speeds. This ratio is ideal in Western Australia where most of the trails are pretty flat single track. The Inbred is a good climber, in that your legs will give out before you lose traction. Long open flats or pedally downhills will have you spinning like a loon if youíre trying to keep up with geared bikes, but youíre much better off freewheeling and taking in the view. Gently undulating single track or technical descents are the ideal tracks for single speeds, though itís actually quite surprising what gradients you can get up when 32x16 is your only option other than walking (though thereís nothing wrong with that!)

Riding a single speed (for an old fart like me) is like winding back the years to when you were ten or so, thrashing about on a knackered old bike and grinning a lot!


If you like the idea of a single speed and want a quality, purpose built frame, the Inbred should be on your shortlist. Itís a comfortable, well-mannered steel frame, with all the features you will need, that should give you many years of dependable use.

It is a long frame, so you might need to adapt your riding style a little if youíre not used to this type of geometry. However, Iím certain that once youíve tried it, you wont look back.

Highly recommended! Performance 5/5. Value 5/5.

Facts and figures


Frame 2002 On-One Inbred DN6 CrMo Steel
Colour White
Size Medium - 18" centre to top
Forks 2004 Marzocchi Marathon S (coil), 100mm travel
Wheels Mavic F519 32h, 3X Sapin spokes, Surly flip-flop rear hub and WTB Laser disc front
Tyres Front and rear: Michelin Mud 2.1"
Brakes Front: Hope mini 185mm disc; Rear: Avid 2.0 brake and lever
Headset Chris King
Stem Titec BigAl 90mm, 0į rise
Bars Answer Pro Taper XC 1" riser
Seat post Thompson Elite 27.2mm x 410mm
Saddle WTB, sstx comfort zone
Chainset Bontrager Race Lite 4-arm 175mm Backspire 32t
Pedals Specialised clipless
BB Shimano UN72 (XT) 68mm x 113mm
Chain Diamondback BMX
Cassette Dicta 16t BMX freewheel
Other I botle cage

Frame geometry, medium - 18" frame

Seat-tube centre to top 18"
Effective top-tube length 23.7"
Chainstay length 16.4 - 17.5"
Head Angle 71į
Seat Angle 73į
BB Height 11.9"
Standover 29.4"
Head tube length 105mm
Fork length 400mm
Frame weight 2.16kg (4.75lb)
Fork weight 1.61kg (3.54lb)*
Bike weight 10.95kg (24.1lb)*
* these weights are for the original setup without gears and with Manitou forks which are lighter than the Marzocchis

email me: fastfish666@DONTSPAMMEyahooyahoo.co.uk