Gearing - wisdom doesn't always come with age

[Dave5N]

Walk it. Much faster..

 

[Randochap]

Walk it. Much faster..

Wrong. Spinning 27" @ 80 rpm = 6.5 mph. Even @ 60 rpm you'll get 4.9 mph. If you can maintain 90 rpm you'll get 7.3 mph.

Since the average human walking speed on flat ground is 3-4 mph -- for someone unencumbered by pushing a bike uphill -- then, I guess a fit cyclist spinning a 27" gear is going to leave the walker behind pretty quickly. Anyway, I can't recall a walker ever passing me on a hill climb. Duh!

No wisdom to be found from Dave, folks; move along.

 

[jimboalee]

I am, of course, one of those "people on here" arguing in favour of triples beyond a certain ratio spread. And my argument is in fact based on the very issue gavintc blames on a triple -- a problem exacerbated with a so-called "compact" double.

Let's say you are in a paceline, cruising along at 25 mph. Up comes a sudden, steep rise in the road. You bail from your 50T ring to the 34.

There, now you've lost momentum; your legs are spinning like mad and your bike drops backwards -- either off the back, or into the wheel behind you, causing a crash.

Now, the alternative would be to throw a few gears on the back, with a multiple sweep, but this is less precise than a simple drop of one ring, which is just ten teeth on an evenly-spaced triple. Yes, there is the off chance you could overshift to the granny, but this is no more likely than any other gearing fumble by an inexperienced rider.

I ride regularly in such a paceline and never have any issues. I do notice some riders do struggle with the big space on their compacts. A friend I rode with yesterday is replacing the 50 on his 50/34 compact with a 48. At least that will shorten the gap from 16T to 14.

Riding in a Paceline, or in the middle of a Chaingang, and a short steep incline appears. On a double - flick both small levers simultaneously. The chain drops to the small ring and drops to the next small sprocket.

In the 'Old days', and I'm sure RandoChap will remember, with Downtube levers, the thumb ( of the right hand ) would push the left lever forward ( front mech ) moments before the Index and middle fingers knuckles would grab the RH lever ( rear mech ) and shift it forward. This is if you were righthanded. Very tricky for lefthookers.

With a 'Compact' or in the 'Old days' an 'Alpine', the rear mech is shifted two OR EVEN THREE sprockets to avoid the "spinning like mad" as Randochap describes.

I used an 'Alpine' 55 / 37 once. Never again. Kept missjudging the rear mech lever movement.
With a 'Compact' today, you just keep ficking the small lever to drop the chain onto smaller sprockets until you've picked up the appropriate gear, but even so, you MUST know your gears to make the correct desision.

Yes, no-one in the chaingang likes a rider who doesn't know his gears.

 

[Randochap]

With a 'Compact' today, you just keep ficking the small lever to drop the chain onto smaller sprockets until you've picked up the appropriate gear, but even so, you MUST know your gears to make the correct desision.

Quite doable (in fact, I use this method for getting "in-between" gears on certain inclines) but still prefer the closer spaced triple, which eliminates most double shifts.

 

[bonj2]

Road, Track, Cross, MTB, BMX

Why does he do cross if he's also got a MTB? does he do 'proper' mtbing? If he does, how can he possibly think cross is as good fun? Do you force the lad to do 'cross?

 

[jimboalee]

Quite doable (in fact, I use this method for getting "in-between" gears on certain inclines) but still prefer the closer spaced triple, which eliminates most double shifts.

Yup. I've a triple on the bike I Audax. Flicking both small levers together gets me two ratios down in a fraction of a second. On a 'Compact' it would be three or even four ratios. Achieving a two ratio change would need a further two flicks of the rear gear changer.
More time = momentum and speed lost. This is why I detest 'Compacts'.

If you can't get into the appropriate gear within ONE second, you'll disturb the rythym of everyone behind you.

 

[bonj2]

is 'audax' a verb?

 

[MacB]

is 'audax' a verb?

I thought you were moving away with jerking movements?

 

[jimboalee]

is 'audax' a verb?

Dunno.

Its "Audax Club Parisien".

The way I understand it is 'to Audax' is to 'journey with audacity'.


I must say, YOU'VE got some AUDACITY raising this question

 

[jimboalee]

A loose Latin translation from a Translation Website is :-

Foolhardy.....

 

[byegad]

A Triple and a big rear granny would be my choice, it's not what you can pedal on the first hill of the day that matters.

Ask yourself how low a gear you'll need with a lot of miles in your legs and a headwind as you hit the big climb.

 

[jimboalee]

Strange, but true.

I have a 50 km 'training route' with a couple of 10% and a short 12% in it.
I go round on my 24lb Dawes at an average of 15 mph using a gear of 43" to get up the 12%.
I go round on my 16.5lb SWorks at an average of 17 mph and use the 55" gear to get up the 12%.

My climbing speed is 2 mph faster on the SWorks.

I go round the route on my 34lb Apollo County and I struggle and strain on its 41" lowest. I only average 12 mph on the Apollo.

Hmmmm… Is gearing relative to bike weight at all ???????

 

[Dave5N]

Why does he do cross if he's also got a MTB? does he do 'proper' mtbing? If he does, how can he possibly think cross is as good fun? Do you force the lad to do 'cross?

Yes. Character-building.

 

[alecstilleyedye]

this table is quite useful…

 

[jimboalee]

this table is quite useful…

There are loads of these around. One was selotaped to the glass counter in Tower Cycles, Erdington.

But who tells you what rings and sprockets to put on a new, self build bike?