Step-by-step guide to fitting a CushCore insert in your tyre, plus coil vs air shocks and tech Q&A
Your questions answered
Going round the twist
I always forget which way my pedals unscrew – have you got any tips on how to remember? Also, how tight do I need to do them up?
James, Llangollen
Everyone has their own trick, but ours is to rotate the crank arm so it points straight down at the floor, or slightly further forwards than that. Then insert the Allen key or pedal spanner with its handle facing the rear wheel axle, and just push down. As the left-hand pedal has an opposite thread, this approach works on both sides. If the pedal won’t budge, you can use your foot to push the Allen key or spanner down. As for tightness, it’s best to check the manufacturer’s recommended torque setting, but generally, tight but not too tight is key. The pedal threads effectively self-tighten as you ride, so while you want to make sure the pedals are properly attached (with a washer installed, if the cranks are supplied with them) you don’t need to do them up too tight – this will only make them harder to remove.
Angle wrangle
Bike geometry charts often list ‘effective seat angle’ – what does this mean and is it different from the seat angle? Charly, via email
The effective seat tube angle (as we prefer to call it, to avoid confusion with the saddle angle), or ESA, is the angle between the ground and an imaginary line drawn from the centre of the bottom bracket (BB) to the centre of the top of the seatpost. On some frames this is the same as the actual seat tube angle (SA) – the angle at which the seatpost leaves the frame. However, on many modern bikes it differs, because the seat tube starts in front of the BB or is kinked to make room for a suspension linkage or bigger 29in/650b rear wheel. Both of
these measurements are useful to know when buying a bike.
The ESA is most important, because it gives the best indication of where your hips will be in relation to the cranks. However, it doesn’t account for leg length (raising the seatpost pushes the saddle back relative to the BB, slackening the ESA) and there’s no industry-wide standard for what saddle height it should be measured at. This is where the SA comes in – by comparing both figures you can get a good idea of how the bike will feel when you’re sat down pedalling, because the bigger the difference between the SA and ESA, the greater the impact raising or lowering the saddle will have. In our biketests, we quote ESAs we’ve measured ourselves, with the saddle set at the same height on each of the bikes.
Winter blues
My electric car’s battery doesn’t work as well in winter – I get less range per charge. Is this the same with an e-MTB? Tamsin, Lockerbie
Yes, but it shouldn’t be quite as noticeable. The reason batteries don’t perform as well in winter is that colder conditions slow down the chemical reactions, producing a lower current that can’t keep your motor running optimally. Car batteries are much higher-capacity, so any loss of range is more obvious – you might find yourself going 40 miles further on a full charge at 20°C than at 0°C. On a bike, you’re looking at a single-digit difference in mileage, and that has to be taken in the context of all the other factors that impact e-bike battery life, from ground conditions to mode selection and your physical input.