Results 1 to 3 of 3
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jul 2013
    Posts
    36

    Help needed 29 vs 26 inch speed

    I need some help from my clyde brethren. I am trying to figure out why my 9r is slow and I mean slow. On a 5 mile loop of single track I am almost 5 miles an hour faster on my 26 inch GT outpost VS my 9R GT timberline. On the road with slicks on the Timberline and semi slicks on the outpost I am 3 miles an hour faster over the same 5 mile course. Anyone have and ideas or links to useful info?

  2. #2
    mtbr member
    Reputation: millertm's Avatar
    Join Date
    Jul 2012
    Posts
    461
    Your RPM's are slower on the 29'er if I am understanding what you are saying. If you are in the same gears, (larger sprocket in front and same in rear) if gearing is same or close between the two bikes. Try and ride in a lower gear on the 29'er and spin faster. Once you get used to spinning faster on the 29'er, then ride in the higher gears. I have been on my 26'er for a few rides and jumped on my 29'er tonight and noticed that I was spinning slower then I did before I got on my 26'er. I hope that this helps some.

    Mark
    2012 XXL Carve Expert

  3. #3
    Always Learning
    Reputation: BruceBrown's Avatar
    Join Date
    Jan 2004
    Posts
    8,870
    Quote Originally Posted by Phinox View Post
    I need some help from my clyde brethren. I am trying to figure out why my 9r is slow and I mean slow. On a 5 mile loop of single track I am almost 5 miles an hour faster on my 26 inch GT outpost VS my 9R GT timberline. On the road with slicks on the Timberline and semi slicks on the outpost I am 3 miles an hour faster over the same 5 mile course. Anyone have and ideas or links to useful info?
    Assuming your computers on both are set up correctly for the wheel and tire size (assuming that's where you came up with the 5 mph figure), the only real way to know are the actual lap times. Even then, you would have to record multiple lap times on many occasions to see if one bike is consistently slower or faster than the other. How many laps to get an accurate reading? I don't know. Even if you were in the best racing shape, fatigue will slow you on each subsequent lap. The tire's rolling resistance comes into play as does wheel weight, tire pressure, overall bike weight, etc... . Not to mention familiarity with a particular bike. How long have you had each and how many laps of the particular 5 mile singletrack loop have you done on each?

    Hook them up to a power meter, and use your HR monitor as well - all while using the same exact tire tread and similar tire pressure with both bikes, and ride on the same day in the same conditions and record all of the data. That will give you a more accurate analysis of what is what between the two. HR, watts, time, calories burned, etc... .

    I can ride the same loop on all 4 of my 29"ers and get wildly different times from each (long travel FS, short travel FS, softail, and SS).
    The 14 warmest years have all occurred in the 16 years since 1997.

Similar Threads

  1. handlebar chatter - nevermind solved
    By jasonjm in forum Shocks and Suspension
    Replies: 0
    Last Post: 07-27-2013, 03:47 PM
  2. Input needed for 9 speed upgrade
    By XC Mike in forum Tandem Mountain Bikes
    Replies: 28
    Last Post: 07-19-2012, 07:32 AM
  3. First Single Speed Bike - Advise Needed
    By horriefic in forum Singlespeed
    Replies: 10
    Last Post: 03-25-2011, 08:15 AM
  4. Shimano 8-speed Alfine servicing needed in San Jose area
    By Leopold Porkstacker in forum Internal Gear Hubs
    Replies: 5
    Last Post: 03-10-2011, 07:35 PM
  5. Shimano 8-speed Alfine servicing needed in San Jose area
    By Leopold Porkstacker in forum California - Norcal
    Replies: 0
    Last Post: 03-08-2011, 05:09 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •