I’m a mechanic - here are 5 jobs you should do yourself, and 5 most home fettlers should avoid

The ‘grumpy mechanic’ is not a stereotype I’d like to conform to. Here in the workshop, we see a huge array of different issues and no two days are ever the same, it’s one of the real joys of our work. However, some jobs are definitely more frustrating than others; there are definitely some jobs that make me more grumpy than others.

There are two strong themes around these jobs. The first: jobs the customer really would be better off doing themselves. The second: jobs they absolutely should not have attempted.

Undercover Mechanic

Cycling Weekly's Undercover Mechanic will be publishing his thoughts on the state of the industry once a month. He's been working with bikes for over two decades, offering servicing on models from some of cycling's best (and worst) marques. You'll find him at all major trade shows and events, just don't expect him to make himself known.

Jobs to do yourself

If you came here hoping to pick up some exciting new tasks you can perform in your garage, you'll be disappointed. The fact is, most of the jobs mechanics wish you'd do yourself are - well - quite mundane. But, whilst they seem basic, experience in the workshop doesn't lie, and you'd be surprised how few people do all of these regularly.

Clean your bike (properly)

Honestly, I shouldn’t really even need to say this, but please learn how to clean your bike, especially before you bring it into a mechanic. When we get bikes in that are covered in crud, we clean them properly before even attempting to resolve any issues. On a fairly regular basis, the cause was simply that the dirt was making it impossible for the bike to work properly. The vast majority of problems that crop up are due to pivots, bearings and cables that can’t move properly because they’re clogged up, causing gears that don’t work, brakes that don’t pull and excessive wear on all of your parts.

All this said, the opposite approach can also cause lots of issues. A large percentage of the hub and bottom bracket bearings that fail are due to all of the grease being washed out of them. There are some popular brands of bike cleaner that are notorious for this amongst mechanics as people get overzealous with their squirty bottles.

There are plenty of videos and guides out there that will show you how to clean your bike properly.

Lube your chain

Almost as a follow on from number one, please learn how to lubricate your chain. If you’re using wet or dry lube, simply apply to a clean chain, one drop on each roller and let it sit for a few minutes to penetrate, then wipe with a cloth to remove any excess. You can improve this penetration by cross chaining to open up the gaps between the rollers and side plates.

Do not get home from a dirty ride, put your bike away and then before the next ride squirt a load of more lube on top of the old grimy stuff. We’ve seen chains like this worn out past 50% within one month.

Keep it tight

Learn how to do an M-Check. This is a simple way to remember how to check for play or loose bolts in key areas. After dirt and corrosion, a bolt simply not being tightened up, is probably the next biggest cause of any issues on the bike. We recently had a very expensive e-bike come into the workshop, the owner had been getting increasingly frustrated with his new purchase which didn’t seem to work. I noticed the back wheel seemed very wobbly and on inspection, it turned out that the rear thru axle had not been done up. As soon as I tightened it, the torque sensor was then properly aligned with the wheel and the whole bike worked perfectly.

Learn how to look after your tyres

Something every mechanic dreads is when an old bike with hub gears and mudguards comes in to have an inner tube change. You can guarantee it will be caked in 10-year-old chain oil and grime and will take probably 40 minutes to get the wheel out and back in all to change a £3 tube. It’s impossible to charge the actual time it’s taken. Luckily we don’t have to do this too often these days and our general rule now is that if someone comes in and asks us to change an inner tube, we teach them to do it and charge them for that. It’s a bit like the “give a man a fish Vs fishing rod” analogy. Also in the same vein, it’s not that difficult to find the correct tyre pressure for your bike and maintain it. Your tyres and pressure probably influence your cycling experience way more than any other part of your bike and they are typically the least thought about in terms of maintenance. “I just pump them up until they’re hard” is a phrase all mechanics will hear regularly.

Adjust your headset

Learn how to adjust your headset. It’s scary how loose some headsets enter the workshop. Headsets can be adjusted with a simple hex key in most instances, with no need for dedicated headset spanners. A loose headset is simply dangerous, as it will cause excessive wear in your bearings and vibration and impacts will fatigue the frame and forks.

Jobs a lot of people should leave to the professionals

A phrase all mechanics will recognise and chuckle at, is when someone comes in with their broken bike uttering that they had a go at it because “I’m an engineer”. Now I’m pretty handy, as you would expect, but just because I can fix most issues on a bicycle doesn’t mean that I would attempt to fix a fighter jet.

Some of these jobs will be well within the capabilities of home mechanics, and, those with experience feel they're 'simple'. However, real-life evidence from the workshop suggests that many home fettlers should simply avoid the following...

Truing wheels

Wheel building and truing not only require skill and experience but these days also some pretty specialist tools. The main issues we see when people have tinkered, is that they always only tighten spokes to pull it into line, which places more stress on the parts and leads to cracks in the rim, broken spokes and rounded nipples. Also, now that most road wheels have bladed spokes, we see a lot of twisted spokes where they weren’t held straight whilst the nipple was tightened. Trust me, the only place twisted spokes look cool is on SoCal Lowriders.

Bleeding brakes

Bleeding brakes has gotten easier in recent years but still requires the correct tools and fluid. For instance, if you put Dot fluid into a mineral oil system, it will destroy the seals leading to total brake failure. Yes, we have seen this

Adjusting temperamental gears

The tolerances in modern 12-speed drivetrains are so tight, that it takes very little for them to go out of adjustment. Electronic shifting has helped a little, as there is no cable friction to worry about but if you don’t know what you are doing, please leave well alone. We have had several cases when the rider has started moving limit and B adjust screws causing the rear mech to then dump the chain straight into the spokes, normally just as you are picking up speed.

And, if this sounds overly simple, then bear in mind that we have seen a bike where cable outer had been used as cable inner - if you're inclined to make a mistake such as this, leave well alone.

Tightening a bolt that keeps slipping

You should be using a torque wrench when checking all of your bolts but if something is still slipping even at the right torque, please do not just keep tightening in the hope that it will grip. If it isn’t gripping it means something is wrong and needs to be investigated. All you are doing is risking stripping the bolt or damaging the parts. Our least favourite job is having to extract seized or rounded bolts from a frame and we charge accordingly! Just whilst on this subject please learn the difference between a Hex bolt and a star shaped Torx bolt. Just because an “Allen” key will fit inside a Torx bolt does not mean you should use it!

Setting up road tubeless tyres

Changing a tyre used to be simple. But, if you get the set up of road tubeless wheels wrong, the results can be catastrophic. Most consumers do not consider the compatibility of tyres and rims and this alone can cause horrible failures. We had a client who had a high speed blow out whilst coming down a mountain pass. Luckily he was fine and got away with no injuries but the large global wheel manufacturer would not warranty his now broken wheel, as the tyre fitted was not on the list of compatible tyres, despite it being probably the best selling tyre in the world. Add to this the complexities of seating the beads correctly, over-pressure release systems and hookless rims, if you are in any way unsure about what you are doing please leave it to a professional.