Tuesday, 10 June 2008

What they don't teach you at the bike store

My mom's friend popped over for tea on Saturday. He'd just been to the shops to buy a new cycling top. He's in his 50's, does Tai Chi and walks a lot. A car sideswiped his vehicle a few weeks ago, so he has been riding 5.6km each way to work and back daily, on his mountain bike. I noticed a limp and asked what was wrong with his right leg. "Arthritis," he replied. And he added that it had flared up in his knee when he started bicycle commuting, probably as a result of doing an activity (cycling) that he is not yet used to.

How many times over weekends have you passed a social biker on the road (with no helmet!) riding with their knees around their ears? I feel a compulsion to stop them and adjust their bikes (and tell them they're morons to be riding without helmets). You should not be able to put your feet on the ground while sitting on the saddle. Saddle height, my friends, is all important.

I talked Earl through the basics of a) setting his saddle height and b) seat position.

At Tai Chi last night my mom overheard Earl telling other participants about "Dr Lisa" and how his knee is improving after only two days; he commuted pain-free on Monday.

While I think the title is neat, this is not rocket science and bicycle shops should be taking each and every new bicycle owner step-by-step through setting up their iron steeds for their comfort (this would count as good customer service).

Unless you're taught this stuff by a more experience cycling friend you just wouldn't know that two centimetres can make a big difference to your biomechanics and riding comfort.

Saddle height
I find it easier to recruit a friend to hold your bike while you're sitting on the saddle; alternatively sit on your bike close to a wall, with one hand against the wall to keep you upright.
Place your mid-foot (widest part of your foot over the pedal axle) on the pedals with the heel pressed down.* Lower one leg so that the pedals are at 12 o'clock and 6 o'clock. There should be a a slight bend in the knee when the pedal is at 6 o'clock; the leg must not be completely straight with the knee locked. A slight bend is what you want. If your current position is not correct, get off, adjust the seat post and test again.

* When you pedal you should force your heel down on every down stroke. This will offer you more propulsion and power from your pedaling. Toes, pointed, on the pedals is for ballet dancers.

Ride up and down the road a few times to see what feels best; make small adjustments each time. If the leg is too straight or you feel like your bottom is shifting from side to side when you pedal, then the seat needs to be lowered.

When you've achieved the right setting, mark the seatpost with a permanent marker. There are situations on a mountain bike that you should have a lower seat position for safety as well as improved agility. This can also be marked on the seat post so that your seat can be adjusted quickly according to the conditions, like flat-out peddaling vs technical downhills.

Seat position/distance
Most saddles can be adjusted forward and backwards as well as tilt. Again get a friend to assist. Position your feet on the pedals at 3 o'clock and 9 o'clock (horizontal, crank arms parallel to the ground). The forward knee should be directly over the ankle (your shin perpendicular to the foot). I gauge my seat distance to be right when I look over the forward knee and can just see a bit of my toes.

If your knee is too far forward (can't see your toes), the seat needs to be moved back. If the knee is too far back (you can see too much of your foot) the seat needs to be moved forward.

Loosen the bolts under the saddle just enough to slide the seat into the correct position. Retighten when you've found the correct position.

A fancy alternative involves getting a friend to hold a weighted string from the front of your forward knee-cap. The string should fall in line with the pedal axle. Move the saddle forwards or backwards until you get the saddle position right.

As for tilt... a slightly nose-down saddle can help to reduce the incidence of back-pain and relieve pressure (useful if you experience numbness where your body meets the saddle). But, this downward tilt can make you feel like you're being pushed forwards (sliding down the nose). The saddle should be at least horizontal and never nose-up as this can lead to problems with circulation and nerve damage.

Handlebar height, brake and gear lever position can also be tweaked; but by far the biggest problems come from saddle height.

While you're helping friends to adjust their bikes, I'm going to contemplate whether it is my social responsibility to halt weekend warriors (those who can put their feet on the ground while sitting on the saddle) in their tracks to adjust their saddle height. Mmmmmm...

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