Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Gearing Confusion

Search
Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Gearing Confusion

Thread Tools
 
Search this Thread
 
Old 08-14-10, 12:07 AM
  #1  
divtag
Senior Member
Thread Starter
 
Join Date: May 2009
Location: Huntington Beach
Posts: 371

Bikes: '09 Salsa El Mariachi, '08 Surly Cross Check, '06 Specialized Rockhopper

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Gearing Confusion

I bought my CrossCheck about a year ago on CL and this is what it came with:

DA Cranks (older): 52/39
Rear: Shimano Ultegra RD 7700
Front: Shimano DA FC 7701
DA Barcon Shifters
and I think 12-25 cassette.

I am not too bike tech savvy. I can change tires, replace brake pads, and clean and lube the chain. I am slowly trying to learn more, but don't know much.

Anyhow, I need to get lower gearing. I don't do group rides, I am not a racer, I don't even wear the typical outfit. I just like going out and riding. Working my way up to century riding and hopefully a tour down the West coast at some point.

I rode three 40 mile rides this past week and noticed that I spend most of my time in the 52-23 (for me ~15-17 mph). I have been riding mostly flat, just up and down under the overpasses, because I don't have the gears (and legs/lungs) to do the climbs. To do the longer rides that I want I am eventually going to have to do the hills. I also ride a MTB (1x9) that is 32 and 12-34. Short steep climbs I can mash up, longer sustained climbs I do a lot of pushing.

Looking at the Sheldon Brown calculator it says the 52-23 is 61. That is all fine and dandy, but I have no idea what that means. Also, as I have been researching and people talk about 1 step or 1 1/2 step and cross chaining. I don't know what any of that is.

Basically, I need lower gearing. I was looking at either of these:

46/30: https://www.velo-orange.com/grcru50cr.html
or
48/36/26: https://www.velo-orange.com/suoldlotr.html

Then I need a wider cassette, maybe something like on my MTB. From what I have read, that means I need a different RD (long cage?). I don't know about FD?
divtag is offline  
Old 08-14-10, 12:27 AM
  #2  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,598

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,357 Times in 863 Posts
Gear inches are a way of describing what we call .. an equivalent wheel diameter ..
so 61" gear ratio is as if it were an old penny-farthing bike with a 61 inch diameter drive wheel.
Or a real big Unicycle wheel.. of same diameter .

cross Chain is using the outer large chainring with the innermost large rear cog , and visa versa, the 2 smallest cog chainrings are literally forced into a heavy side flex as it goes around, wears out the chain , and a well thought out gear ratio set has that same ratio in a better chainline.

Ideal chain line is middle chainring in the front , and middle cog in the rear stack
# 3 of 5, #4 of 7, #5 of 9, etc.
they should be in the same plane , parallel to the centerline of the frame.

the 48 36 36 (or 24t) triple would be better with a Mountain front derailleur, but the current stuff for MTB/ are 44 t
may work .. their Trekking stuff is for bigger chainrings like a 48 but may not be in many dealers suppliers stock list.

If you were to compete in cyclocross the 46 30 is a decent choice the chainguard
plus a chain'minder on the inside should keep the chain from bouncing off on rough ground..

Last edited by fietsbob; 08-14-10 at 12:39 AM.
fietsbob is offline  
Old 08-14-10, 12:36 AM
  #3  
fuzz2050
Real Men Ride Ordinaries
 
fuzz2050's Avatar
 
Join Date: Sep 2008
Posts: 3,723
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
you have plenty of options

Option one: You can replace your current cassette with one that has a larger cogs, you can probably go as big as 30 (28 for sure). This relatively simple change would lower your lowest gear from 45 to 35 gear inches.

You could also replace your crankset with a compact crank, like the gran cru crank you linked to. A compact crank is a double crank that has smaller chainrings than a conventional crank (usually around 48/34). You can probably install that crank using your current front and rear derailer. That particular crank would give you a low gear of 30 gear inches with your current cassette, or 26 if you swap out your cassette as well. If you do this, your derailer might have trouble with the chain slack if you use your small/small combination, but as long as you're cognisant of this risk, you should be allright.

If you want true stump pulling gears, you're going to need a triple. This will require not only a new crankset, but also a new front and rear derailer. It would be an expensive endeavour, but you could get immensely low gears.
fuzz2050 is offline  
Old 08-14-10, 08:35 AM
  #4  
HillRider
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656

Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,096 Times in 742 Posts
Originally Posted by divtag
I spend most of my time in the 52-23 (for me ~15-17 mph).
This is the part I don't understand. If you want lower gears, why not use the 39T chainring more? A 52/23 combination is the same as a 39/17 combination and gives you several lower gears beyond that.

I understand the need for lower gears for climbing but you should make better use of what you already have.
HillRider is offline  
Old 08-14-10, 09:46 AM
  #5  
divtag
Senior Member
Thread Starter
 
Join Date: May 2009
Location: Huntington Beach
Posts: 371

Bikes: '09 Salsa El Mariachi, '08 Surly Cross Check, '06 Specialized Rockhopper

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by HillRider
This is the part I don't understand. If you want lower gears, why not use the 39T chainring more? A 52/23 combination is the same as a 39/17 combination and gives you several lower gears beyond that.

I understand the need for lower gears for climbing but you should make better use of what you already have.
Because I can't climb the hills withe lowest gear the 39 offers, not even close. Even on the commute home with my panniers on with my laptop and other gear I could use lower gears on the one medium size hill that I have right before I get home.

For general riding, we have some big hills in CA. Many of the century type rides go over these hills. The 59-23 is when it is flat and no headwind.
divtag is offline  
Old 08-14-10, 10:34 AM
  #6  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,598

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,357 Times in 863 Posts
My 'cross' bike has a 50,40, 24t triple and a 13-28t rear cluster, it works well .
low is 24/28 or 6/7ths = .8571428 :1 ..

if you got gear in the bags from the grocery run in the bags, and live on a hill,
a mountain bike drivetrain will shift OK with the bar end shifters..

many new touring bikes use that, or the road triple that adds that 30 to the 39 in the middle.

Last edited by fietsbob; 08-14-10 at 10:38 AM.
fietsbob is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
OregonHepcat
Touring
32
04-25-19 01:57 PM
bluefoxicy
Bicycle Mechanics
18
04-30-11 05:53 PM
MacAttack
Cyclocross and Gravelbiking (Recreational)
8
07-29-10 05:31 PM
lebowskii_98
Bicycle Mechanics
3
05-25-10 06:46 PM
seenoweevil
Clydesdales/Athenas (200+ lb / 91+ kg)
26
03-14-10 12:00 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.