Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Clydesdales/Athenas (200+ lb / 91+ kg) Looking to lose that spare tire? Ideal weight 200+? Frustrated being a large cyclist in a sport geared for the ultra-light? Learn about the bikes and parts that can take the abuse of a heavier cyclist, how to keep your body going while losing the weight, and get support from others who've been successful.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 11-02-08, 04:05 PM   #1
flip18436572
Triathlon in my future???
Thread Starter
 
flip18436572's Avatar
 
Join Date: Jun 2007
Location: Southwest Iowa
Bikes: Junk, that is why I am here. :-)
Posts: 2,193
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Can I ask a Cranky question?

What is the difference in crank length?

What should I use and how should I know?

I am 6' 3", but have a 33" inseam. I am using the stock cranks that came on my Jamis, but I am thinking of changes to make to the bike for next year and putting things on a Christmas list for the family. I haven't looked into pricing, so this might not even matter, but I am interested in finding out.

THANKS!!!!!
__________________
2007 Jamis Ventura Comp
2006 Jamis Explorer 2.0
2000 Specialized Hardrock (bought used)
Swim, Bike, Run and sounds like fun
flip18436572 is offline   Reply With Quote
Old 11-02-08, 04:58 PM   #2
Mr. Beanz
Banned.
 
Mr. Beanz's Avatar
 
Join Date: Dec 2005
Location: Upland Ca
Bikes: Lemond Chambery/Cannondale R-900/Trek 8000 MTB/Burley Duet tandem
Posts: 20,030
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I have 175 on my Lemond and 172.5 on my Cannondale. I don't notice a darn difference. Some say longer cranks allow a rider to apply more torque. SHorter carnks for spinning and long cranks for hammering. Some say longer cranks for climbing. I don't feel a thang!

Look at the thread I post a few days ago "anybody buy from these guys". Ther is a link to some inexpensive cranks at an online ebay store. Ultegr triple for $149 including the bottom bracket.

I went of the 10 speed setup, works fine with 9 speed drivetrain. I like the 10 speed acuse it is the new outboard bearing design. Much stiffer and durable. Old style is the bearing in the cartridge sytle. More toward the center of the BB allowing more flex and chance of damage/loosening..
Usual online price is $250 without the BB (which is usuall about $50 more)
Mr. Beanz is offline   Reply With Quote
Old 11-02-08, 06:32 PM   #3
Bone Head
Senior Member
 
Join Date: Dec 2007
Location: Virginia Beach, VA
Bikes: 2006 Giant OCR Limited
Posts: 479
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
one consideration... when pedaling thru a turn and 'leaning into a turn' with the inside pedal @ 6 o'lcock, the longer cranks reduce the amount you can "lean into" the turn. you are more apt to 'catch the pedal' on the road. some may not consider the small increase in length significant, but it is simple geometry... it can make for a nasty spill....

....... did that babble make sense???
Bone Head is offline   Reply With Quote
Old 11-02-08, 07:04 PM   #4
Mr. Beanz
Banned.
 
Mr. Beanz's Avatar
 
Join Date: Dec 2005
Location: Upland Ca
Bikes: Lemond Chambery/Cannondale R-900/Trek 8000 MTB/Burley Duet tandem
Posts: 20,030
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Bone Head View Post
one consideration... when pedaling thru a turn and 'leaning into a turn' with the inside pedal @ 6 o'lcock, the longer cranks reduce the amount you can "lean into" the turn. you are more apt to 'catch the pedal' on the road. some may not consider the small increase in length significant, but it is simple geometry... it can make for a nasty spill....

....... did that babble make sense???
No! Depending on a .009 of an inch to make that much of a difference? A smart rider knows when to pedal and when not to pedal! I've smoked too many riders down mtn switchbacks. 30-40 mph switchbacks and descents for 20-30 miles and "Never" do I pedal through a turn! Knowing how to take the turn is way more important than where your pedal is at on the downside.

Also on flat turns (crit race types), you hesitate with the pedals at the lowest point of the turn. You don't risk pedaling hoping .009 will save you!

Ever watch TDF videos of the timetrials? Ever see the riders stop the pedals while taking sharp turns? Yes, then they continue after the sharpest point. Same with driving, you don't accellerate into a turn.

BTW, have you ever read or seen diagrams on the most effective way to take turns? By taking the apex? If you learn how to porperly take turns, you will improve your turn speed and efficiency and NEVER hit the pedals!

Last edited by Mr. Beanz; 11-02-08 at 07:08 PM.
Mr. Beanz is offline   Reply With Quote
Old 11-02-08, 07:39 PM   #5
flip18436572
Triathlon in my future???
Thread Starter
 
flip18436572's Avatar
 
Join Date: Jun 2007
Location: Southwest Iowa
Bikes: Junk, that is why I am here. :-)
Posts: 2,193
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
So the length of the crank really doesn't depend upon the rider's inseam length at all, like I thought it would. I was thinking longer cranks for longer legs.
__________________
2007 Jamis Ventura Comp
2006 Jamis Explorer 2.0
2000 Specialized Hardrock (bought used)
Swim, Bike, Run and sounds like fun
flip18436572 is offline   Reply With Quote
Old 11-02-08, 07:50 PM   #6
dbikingman
Senior Member
 
dbikingman's Avatar
 
Join Date: Sep 2007
Location: Spokane/Tri-Cities WA
Bikes: mountain bike, road bike
Posts: 1,352
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by flip18436572 View Post
So the length of the crank really doesn't depend upon the rider's inseam length at all, like I thought it would. I was thinking longer cranks for longer legs.
What I have read is most manufacturers use longer cranks on the larger frame sizes. So I guess they do figure taller frame, longer inseam, longer crank.
dbikingman is offline   Reply With Quote
Old 11-02-08, 08:22 PM   #7
Wogster
Senior Member
 
Wogster's Avatar
 
Join Date: Jul 2006
Location: Toronto (again) Ontario, Canada
Bikes: Norco Bushpilot (out of commission), Raleigh Delta
Posts: 6,941
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Mr. Beanz View Post
No! Depending on a .009 of an inch to make that much of a difference? A smart rider knows when to pedal and when not to pedal! I've smoked too many riders down mtn switchbacks. 30-40 mph switchbacks and descents for 20-30 miles and "Never" do I pedal through a turn! Knowing how to take the turn is way more important than where your pedal is at on the downside.

Also on flat turns (crit race types), you hesitate with the pedals at the lowest point of the turn. You don't risk pedaling hoping .009 will save you!

Ever watch TDF videos of the timetrials? Ever see the riders stop the pedals while taking sharp turns? Yes, then they continue after the sharpest point. Same with driving, you don't accellerate into a turn.

BTW, have you ever read or seen diagrams on the most effective way to take turns? By taking the apex? If you learn how to porperly take turns, you will improve your turn speed and efficiency and NEVER hit the pedals!
Tthe difference in crank lengths is often 2.5mm, which is .098" not .009", still, mountain bikes tend to have longer cranks (175mm vs 172.5mm for road bikes), and the training for starting mountain bikers, is to hold the pedals at 9 o'clock and 3 o'clock when going around curves or between things that can catch a pedal. However your unlikely to see a curve on a normal road that is sharp enough to require enough lean to catch a pedal.
Wogster is offline   Reply With Quote
Old 11-02-08, 09:46 PM   #8
Mr. Beanz
Banned.
 
Mr. Beanz's Avatar
 
Join Date: Dec 2005
Location: Upland Ca
Bikes: Lemond Chambery/Cannondale R-900/Trek 8000 MTB/Burley Duet tandem
Posts: 20,030
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Oops, that's right, got my decimal mixed up!...almost 1/10 of an inch!
Mr. Beanz is offline   Reply With Quote
Old 11-03-08, 12:34 AM   #9
aenlaasu
Senior Member
 
Join Date: Oct 2008
Bikes:
Posts: 439
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The 175 mm crank length is in general fine for most people. While what one poster said about the spinning and torque is correct, it's really only a real consideration for more extremes of height for the rider from what I understand.

http://www.nettally.com/palmk/crwives.html

That's a site I found with some theoretical information about crank length. Whether it is true or not, I don't know, but something to consider any way.

For my own experience, I did research crank length earlier this year when I had to replace my left hand crank. I had a short cranks outfitted with my trike on order under recommendation from the manufacturers. Unfortunately, it's a road bike chainset, 3 chain rings with 155 mm cranks, which seem downright impossible to find any more. I tried 170 mm cranks and to be perfectly honest, it was brutal on my knees. Of course, I have bad knees and at 5'2" (with 26" inseam) the range of flex I was doing with the longer cranks was not kind to my knees or in the interest of my best power delivery.

Thankfully, I found a cycle shop in CA who had my chainset with the short cranks and all in back stock.
aenlaasu is offline   Reply With Quote
Old 11-03-08, 01:14 AM   #10
djnzlab1
Senior Member
 
Join Date: Jul 2008
Bikes:
Posts: 620
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Speed bumps can be fun

HI,
i have a rather large bike and went over a tall speed bump seemed fairly straight forward until my right crank bottomed out on the peak of the speed bump, not a good feeling as the bike lifts up a bit into the air on the crank pedal talk about weird, i manged to come down with out crashing but it reallly hammered the crank..
So I now coast with the pedals in the middle if there's a speed bump...

most really bad wrecks seem to follow a crank bump, my guess is the energy of the bike is transfered back thru the crank to the object involved if its heavier , you go airborne.
djnzlab1 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 08:27 AM.