Get Pumped! 💪

Everything you wanted to know about pumping up your tyres but were afraid to ask

My covid recovery is a bit like Paula Abdul’s “Opposites Attract”: 🎶 Two steps forward, two steps back 🎶 (I am showing my age here). My cough has mostly left now, but heart palpitations have taken its place! Sigh. I continue to rest my ass off.

My writing screen time is limited, so I have burrowed into the mailchimp archives and found some gems of past newsletters, namely the ones that have incredibly useful maintenance morsels. Please enjoy this Maintenance Reminder Email from Jenni in 2019 while I recuperate. I have even added an update about tubeless!

And don’t forget, our £75 Summer class sale is ongoing, y’all have snapped up most of June’s classes so we’ve decided to extend it 🔥

Take it away 39 year old Jenni…

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Today's Topic is:

Pumping Up Tyres

Keeping your tyres pumped up to their correct pressure will help prevent punctures, protect your rim, and provide you with a pleasurable ride. 

Pumping tyres is also really great for your triceps. 

How much to pump? 

We get asked this question a lot, and the delightfully frustrating answer is it depends. Your first port of call is the sidewall of your tyre - it should give you a range, like 50 - 80 PSI or 3.5 - 5.5 Bar. (Kilopascals also exist, but idk anyone who uses those.)

PSI stands for pounds per square inch, and is a unit of measuring pressure. Bar is also used to measure pressure; those of you who scuba dive are probably familiar with this term. But it's used more on the Continent than in the UK (imperial innit). 

Whether you stick to the upper or lower end of this range is up to you, as well as your terrain. Running a slightly lower pressure will be more comfortable and good for inclement weather. Practically essential for offroad. But at full blast you'll get more protection from potholes, and the bike will feel faster.

BEWARE: if your tyre is super old, or if you have non-clincher (hookless!) vintage steel rims, don't pump to the full amount, go about 20-30 PSI below. Otherwise the tyre could come off the rim (no hooks to hold it in) and the innertube will sneak out and explode. How to tell if you have a steel rim? Use a magnet - steel is magnetic, alloy is not.

What About Tubeless?

[Edit from Jenni in 2023]

Tubeless tyres are not meant to be pumped up to the higher pressures of its tubed cousins. This is because there is no innertube for the tyre to protect from snakebite punctures (the kind you get from under inflation). The tyre itself is doing all the work.

For those of you who are running tubeless, you’ll still follow your tubeless specific tyre’s recommended pressure range. Stick to the middle or head a bit towards the lower end of the spectrum. If it only gives you one number, definitely pump less than the recommended PSI, like 20 below.

note the ‘hooked’ and ‘hookless’ options on the sidewall

Hooked and hookless here refers to the rim. Many new tubeless rims are hookless, meaning they don’t have the clincher hooks on the inside edge to hold the tyre in under high pressure. But like its distant vintage grandparent, if you pump up too much, the tyre could come off and explode!

The rim also holds important data. See here how this rim tells us that a different sized tyre will have a different PSI! Fascinating. If you have conflicting data between the rim and tyre, err on the side of the rim’s information.

Generally speaking, the wider/bigger the tyre, the lower the PSI. This is because it is a high volume tyre, and not a high pressure tyre.

What kind of valve do I have?

Whether you are tubed or sans tube, you'll need to know if you have a Schrader or Presta valve to use your pump correctly. Some pump heads are universal but most make you choose. S will mean Schrader, and P will mean Presta. Learn which kind you have! If you have a third kind (Ye Olde Woods Valve) replace that tube next time with a Schrader, stat.

How often do I pump?

Invest in a good quality track pump with a gauge, and pump up your tyres every couple of weeks. Do this on a regular basis, and soon you'll learn what your tyre feels like at proper pressure with a squeeze of your fingers. (My favourite is the Joe Blow Sport pump, if you’re asking for a recommendation.)

It's good for you, your bingo wings, and your bike!

Your friendly neighbourhood mechanics will thank you...

One last thing.

If you want to learn a bit more, here’s a thrilling Cycling Tips Podcast that features the wonderful Jan Heine, where he argues that wide tyres with much lower pressure are actually more efficient in the racing world. Gripping stuff.

(you can tell this is staged, I would never wear white shoes)

If you’d like to learn more about tyres, tubes, pumping, and basic bike maintenance, head on down to our Introduction to Maintenance class! Perfect for total n00bs, we specialise in making beginners feel right at home.

If you’re bike-curious and want to expand your knowledge, we’ve got classes for that too!

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My now discontinued book, How to Build the Bike, is looking for new eyes, new hands, and a new home. The numbers are going down, my faith in humanity is going up!

Get your limited edition signed copy here

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I leave you with another LBK pandemic masterclass, Intro to Cleats & Pedals: this time I’m discussing the basics when it comes to clipping in (or going clipless - I know, it’s confusing, I didn’t make up the terminology. It’s a holdover from toe clips.)

Thank you for the kind words and recommendations for covid recovery replies to my previous email. Your words buoy me in this sea of uncertainty!

Ride on,

Jenni x

ps. I have only just heard/read about Stone Age Cycling’s atrocious new policy for trans and nb cyclists - hot take coming soon. This Cyclist magazine piece is great though.