How to turn an old hardtail into a super commuter
If you have an old mountain bike or an unloved frame in the shed, this could be the perfect base for creating a super-commuter build.
With a few carefully chosen components, you can breathe new life into a bike otherwise doomed to gather dust.
And that’s exactly what we’ve done here, converting an old hardtail into a thoughtful commuter bike for the commute to work.
Let’s start with the frame.
You can convert any hardtail into a decent commuter bike, although the older it is the more likely you are to run into issues due to outdated ‘standards’.
We used a Stanton Sherpa 853 29er as the base for this build.
Originally reviewed on BikeRadar in 2016, it’s still a perfectly good frame but, with its non-Boost hub spacing, quick-release dropouts, lack of internal dropper post routing and relatively short reach, it no longer ready for trail chores.
Before planning your build, you’ll need to check if your frame’s head tube is sized for a tapered or straight steerer fork and what rear axle standard it requires (QR or bolt-on, Boost or non-Boost).
There is no need for front suspension on most trips. Instead, a rigid fork will save weight and be maintenance free.
If it has a slightly shorter axle-to-crown height than the fork originally fitted to your frame (allowing for sag), it will steepen the geometry a bit – which is not a bad thing for road climbs – without lowering the bottom bracket as much.
Most steel forks, like this one from Identiti, have straight steerer tubes, so will require a new lower headset cup or crown race adapter to fit modern frames. If you have the money, the likes of Kinesis, Ritchey and ENVE offer tapered carbon fiber models.
At the more affordable end of the market, Carbon Cycles offers eXotic tapered alloy or carbon forks, starting from under £100.
3. Transmission and brakes
The beauty of a build like this is that you can use whatever old bits you have – in this case, a Shimano 10-speed drivetrain and some Hope plugs.
Unless they’re worn out and need replacing, your bike’s current parts should be up to snuff. MTB brakes and gears will work well for commuting, although you’ll probably want to fit a larger chainring.
Flat pedals are a good choice for a bike that’s going to be a general runaround, with clip-on pedals a better bet for longer rides.
- Plateau : Narrow/Wide Race Face Chainring, 38t
4. Finishing kit
As for the finishing kit, a stiff seatpost will suffice, and requires less maintenance than a dropper, so no changes are needed here.
Any old handlebar is fine, but consider cutting it off to squeeze through traffic. You may want a longer than usual stem to slow down the handling, with most rides having higher speeds and fewer sharp turns than MTB rides.
Don’t forget a bell – the Knog Oi here is kind and unobtrusive, and it’s a godsend on split paths, where a slight “ting” gets a better reaction than a shout or cough.
We opted for a brown saddle and grips to add a bit of urban class.
- Bell: Knog Oi classic bell
- Saddle: R Series Gusset Saddle
- Handles: Deity Knuckleduster Grips
Most commuting doesn’t require big tires on wide rims – they’ll just slow you down. You can fit an older set of cross-country hoops, or – on a 29er like this – lighter, faster road bike wheels (700c and 29er rims are the same diameter), if you like. find cheap.
However, watch the hub spacing – newer road wheels may have 10x135mm (QR) or 12x142mm (non-Boost, bolt-on) MTB compatible axles, but older ones may be 10x130mm or 12x135mm .
Also check to see if they have Center Lock or six-bolt rotor mounts (a problem we encountered, solved with the use of an adapter). You can still run an MTB cassette on a road hub, with a spacer.
- Adapter: Aztec Center Lock Adapter
If the rims are narrow enough, you will have the choice between road, gravel or slick/semi-slick MTB tires. Just make sure the tire size and internal rim width are compatible (WTB has a good guide).
For a short ride, you can use any rubber you have available, even semi-bald MTB treads.
If you go further or ride every day, faster tires will get you there faster and with less effort. We went for the balance of speed and grip provided by some Pirelli gravel tires. A tubeless setup is a good way to reduce flats.
- Tires: Pirelli Cinturato Gravel H 700x40c tires
UK law requires you to run a white front light and a red rear light between sunset and sunrise on public roads – mounted to your bike, not your helmet – plus a red rear reflector and pedal reflectors orange (not shown).
We installed a set of ex-test Lezyne lamps. The front Mega Drive 1800i is a mountain bike light and offers plenty of power for off-road sections, if you still want to venture away from traffic, but can be dipped at 250 lumens on the road.
The rear can be synched to change modes simultaneously (from flashing in traffic to solid on an unlit bike path, for example).
BikeRadar’s roundup of the best bike lights has options for a range of budgets.
- Front light: Lezyne Mega Drive 1800i
- Rear light: Lezyne KTV Pro Smart 75
Mudguards (not pictured) are essential for winter driving – and in the UK, at many other times throughout the rest of the year too. What you can run will depend on the fixtures in your setting.
At worst, you should be able to fit a front fender to keep dirt out of your eyes and a rear seatpost-mounted guard to keep road spray from soaking your shorts.
It is also worth thinking about luggage. While it’s easy enough to pack your kit into a backpack, panniers (if your bike has rack mounts) or frame bags will help keep your back from sweating.
Always have the essential spares – a bike pump, a spare tube (or tire plugs, if using tubeless tires) and a multi-tool – just in case.
How to electrify your vehicle
The latest e-bike conversion kits even allow you to electrify your machine, if you want to go all the way.
For this build, we used the Swytch kit, which contains a handlebar-mounted battery, a front-wheel-mounted motor, and a pedal sensor.
1. Power supply
Many e-bike kits require you to ditch your water bottle holders or install a rear rack to secure the battery.
Swytch uses a bar-mounted bag instead, which also houses the “brain” of the system and the mode dial.
The standard Eco kit has a 180Wh power pack, but pictured here is the 250Wh Pro version, which has a longer range (50km, claimed, at half power) and an integrated front light.
Swytch also recently unveiled a smaller pocket battery, which will be available for pre-order from May for delivery in late summer 2022.
Latest offers on previous Swytch eBike conversion kits
2. Drive unit
Here, a 250W brushless DC geared hub motor provides the pedal assist. Swytch supplies it as part of a complete front wheel.
With 40Nm of peak torque it has half the grunt of many e-MTB drive units, but on a faster, lighter bike (the kit only adds about 3.3kg) feels surprisingly snappy – although the all-wheel drive does take some getting used to on looser surfaces (for mountain biking, we’d opt for a crank system instead).
The bolt-on hub slots snugly into the fork dropouts, and we had no trouble aligning the brake caliper. It is advisable to install a torque arm for added safety.
3. Pedal sensor
This is the trickiest part of most kits to install, especially if you want a neat finish.
Swytch offers different holders for the magnetic ring. We could have used the utility knife that attaches to the crank arm, but opted to grab a Stanley knife from one of the clip-on options instead.
The shape of the frame meant we had to break off the base of the sensor itself to line things up. We also added an extension cable to route the sensor wire through the Sherpa’s top tube guides.
Choose an electric bike kit
There are many kits on the market, which differ in price, compatibility, ease of assembly, and whether they use a hub or mid-drive (crank) motor.
They won’t give the same performance as a purpose-built e-road bike, but will make all the start stops at junctions less grueling and lend a helping hand up the hills.
Just make sure you choose one that is road legal – assistance should only be provided while pedaling and should be discontinued at 25kph/15mph. Here we’ve opted for the hub-based Swytch kit, which has the benefit of UK-based customer support. It is well packaged and simple to install, but only works with QR forks.
We’ve been impressed so far – stoplight acceleration is excellent and while it won’t propel you up hills, it does make steep climbs less sweaty and strenuous.