Question: is a 34/50 compact crank to small to work well on flats using a nine speed 12/26 cog?

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Guys,

Question is a 34/50 compact crank to small to work well on flats using
a nine speed 12/26 cog?

We have healthy hills in the Ozarks, but certainly not "Alpine"
inclines.

Randolf

 

[Ozark Bicycle]

[email protected] wrote:
> Guys,
>
> Question is a 34/50 compact crank to small to work well on flats using
> a nine speed 12/26 cog?
>

A 50/12 is a 112 inch gear. Seems plenty long, unless you're racing in
fast company.

> We have healthy hills in the Ozarks, but certainly not "Alpine"
> inclines.
>

What area of the Ozarks do you ride in?

 

[[email protected]]

Western...you have a bike shop or something?

 

[[email protected]]

[email protected] wrote:
> Guys,
>
> Question is a 34/50 compact crank to small to work well on flats using
> a nine speed 12/26 cog?
>
> We have healthy hills in the Ozarks, but certainly not "Alpine"
> inclines.
>
> Randolf

Do the math. Gear inches * RPM / 336.3 = MPH.

50/12*26.5 = 110.4 gear inches. * 90 RPM (a nice all day long day
after day spin) = 9,937.5 / 336.3 (constant from working through the
formulas of how far one wheel revolution takes you) = 29.55 MPH.
Unless you are wind and gravity helped, I doubt any besides
professional racers can maintain that pace for more than a mile or two.
Go up to 100 RPM, easily maintained for a long time, and you get a top
speed of 32.83 MPH. Moving pretty fast there. Go up to 110 RPM,
easily held for many minutes by anyone who can actually turn big gears,
and you get 36.12 MPH. Take it up to 120 RPM, you can spin this for
several minutes, and you get a speed of 39.40 MPH. Unless you are
going down a mountain you won't be riding 39.40 MPH for very long.

On the low end you have a 34x26. 34.65 gear inches. Pedaling 70 RPM
up a long climb and you are moving at 7.21 MPH.

I presume you currently ride a bicycle. With a cyclocomputer. Look at
your speeds during your ride and what gear you are in. Then go home
and figure up what your RPM was. Figure up how often you ride in the
highest gears.

 

[[email protected]]

Ozark Bicycle wrote:
> [email protected] wrote:
> > Guys,
> >
> > Question is a 34/50 compact crank to small to work well on flats using
> > a nine speed 12/26 cog?
> >
>
> A 50/12 is a 112 inch gear. Seems plenty long, unless you're racing in
> fast company.

Anything bigger than 50-12 would only be needed were you a fast
sprinter who lost races because you didn't have a big enough gear.


> > We have healthy hills in the Ozarks, but certainly not "Alpine"
> > inclines.

If you have long descents you may occasionally wish you had a bigger
gear than 50-12, but that would not be often. Anyway there is always a
descent somewhere that could make use of a bigger gear than what anyone
might have on their bike. I think 34-50, 12-26 is a perfect combo for
rolling to semi-steep hills. It is what I recommend to my friends who
ask my opinion on that sort of thing. I personally use 39-53, 12-25 but
that is only because I like a low cadence.

Joseph

 

[alans]

>is a 34/50 compact crank to small to work well on flats using
>a nine speed 12/26 cog?

Looks like approx 3 rpm pedal cadence per 1mph in 50/12 with 700c wheel
and 23mm tire. So how fast do you go, and and how fast do you pedal?

50/12 examples:
20mph - 60rpm
30mph - 90rpm
40mph - 120rpm

 

[[email protected]]

Actually 80rpm is where I can hold it for as long as I'm awake. I've
tree trunk legs...low rpms seems to make me more efficent. So, to hold
30mph for an hour I need something like 52/11? Wish I had a flat track
to see how long I could hold it.

Randolf

 

[D'ohBoy]

<snip q and comments re 50/12 and flats>

I am happy with my 50/13 on the flats. I am a partially reformed
grinder. I also purchased an 11/23 which I used for a bit but will now
only put on for the flattest rides.

D'ohBoy

 

[[email protected]]

Commuting five days a week 5.5 miles each way average 24mph on the
flats. Though there are hills which slow me down. Currently though I
ride 52/14 gearing on top and 42/28 on bottom.

Randolf

 

[[email protected]]

Maybe I'd be better served with a 53/39 and a 12-26 cog?

Randolf

 

[Ozark Bicycle]

[email protected] wrote:
> Western...you have a bike shop or something?

I run a bike service facility. Maintenance/service, repairs, mods,
"updates", etc. I don't sell bikes.

"Western"? Where?

 

[Ozark Bicycle]

[email protected] wrote:
> Maybe I'd be better served with a 53/39 and a 12-26 cog?
>
>

Are you looking for a lower low, a higher high, or both? (FWIW, a 39/26
is the same low as a 42/28, so you'd be spending money for two new
chainrings and a new cassette solely to get a higher high. A 53/12 is
pretty high gear, how often would you use it?)

 

[Tim McNamara]

In article <[email protected]>,
[email protected] wrote:

> Question is a 34/50 compact crank to small to work well on flats
> using a nine speed 12/26 cog?
>
> We have healthy hills in the Ozarks, but certainly not "Alpine"

No. Unless you are racing and need to be able to sprint at 40 mph.

I use a 48/34 crank with an 11-28 cassette on my brevet bike. I can
ride over 35 mph in the 48 x 11 (which is about the same as a 52 x 12),
but I really never have reason to do so.

Modern road bikes are generally geared for racing, for marketing
reasons, with gears that relatively few people can use effectively. I
think that's one of the reasons that most of the bikes you see being
ridden by normal people are hybrids. BIke makers could sell more road
bikes if they'd stop confusing "road bike" with "race bike."

 

[Tim McNamara]

In article <[email protected]>,
[email protected] wrote:

> Maybe I'd be better served with a 53/39 and a 12-26 cog?

Probably not.

 

[[email protected]]

[email protected] wrote:
> Actually 80rpm is where I can hold it for as long as I'm awake. I've
> tree trunk legs...low rpms seems to make me more efficent. So, to hold
> 30mph for an hour I need something like 52/11? Wish I had a flat track
> to see how long I could hold it.
>
> Randolf

30 MPH for an hour? Oh my! Jan Ullrich raced the 50 km flat time
trial in the Giro today at 51.02 kmh (31.8 mph), 58 minutes, 48
seconds. Pretty close to an hour.

30 MPH * 336.3 constant / 80 RPM = 126.11 Gear Inches

52x11 = 125.27 gear inches
53x11 = 127.68 gear inches

 

[[email protected]]

I think I'm sold on a 50/34 using a 12-26 cog. Best of both worlds...a
little lower gear for those mean hills and a little more high for
coming down the backside. Unfortunelately I never get to pedal down
hill cause there are always stop lights at the bottom of each hill

Now if I could only find a XL compact frame with 50/34 chain wheel and
a 12-26 cog with at least a 105 derailure. I'd be in hog heaven

Randolf

 

[[email protected]]

Hmmmm...anyone knows where I can get some steriods? I know I could do
it if I doped for a year or two.

Randolf

 

[Sorni]

[email protected] wrote:
> Hmmmm...anyone knows where I can get some steriods? I know I could do
> it if I doped for a year or two.

Do what?

 

[[email protected]]

Steroids...juicing...doping. Think I could be fast if I had some
chemical enhancement.

 

[[email protected]]

Even better doping and training while listening to Slayer!!! I'd beat
Jan Ullrich or die trying

Randolf