|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Burgundy Street Climb on a fixed gear (Melb)
I was feeling a bit energetic this morning and decided to ride all the way
up Burgundy St (Heidelberg) on my fixed gear roadie instead of turning left onto Studley Rd at the hospital. I am running 45/16 gearing with 170mm cranks on the fixie and was going great guns until about the pedestrian overpass where I really started to slow down and feel the low cadence a bit. By the time I got to the last 20 metres or so where it kicks up and turns to the left I was going really really slow and it was lucky that I managed to score a green light because I don't think I would have been able to get going again from a standstill!!! I have only just put a speedo on my fixie and I managed to hit 50km/h going down the hill past Ivanhoe Cycles and using the following logic I think that this is about 135 rpm or so........ 50,000 m/h / 60 = 833.333 m/min 0.7m x pi = 2.199 m/revolution (for 700c wheel) 45 / 16 = 2.8125 wheel revolutions per pedal revolution 2.199 x 2.8125 = 6.185 m / pedal revolution 833.33 / 6.185 = 135 pedal revolutions per minute (give or take) Let me know if anyone picks any mistakes in my calculation. Gags |
Ads |
#2
|
|||
|
|||
Burgundy Street Climb on a fixed gear (Melb)
Gags Wrote: I was feeling a bit energetic this morning and decided to ride all the way up Burgundy St (Heidelberg) on my fixed gear roadie instead of turning left onto Studley Rd at the hospital. I am running 45/16 gearing with 170mm cranks on the fixie and was going great guns until about the pedestrian overpass where I really started to slow down and feel the low cadence a bit. By the time I got to the last 20 metres or so where it kicks up and turns to the left I was going really really slow and it was lucky that I managed to score a green light because I don't think I would have been able to get going again from a standstill!!! I have only just put a speedo on my fixie and I managed to hit 50km/h going down the hill past Ivanhoe Cycles and using the following logic I think that this is about 135 rpm or so........ 50,000 m/h / 60 = 833.333 m/min 0.7m x pi = 2.199 m/revolution (for 700c wheel) 45 / 16 = 2.8125 wheel revolutions per pedal revolution 2.199 x 2.8125 = 6.185 m / pedal revolution 833.33 / 6.185 = 135 pedal revolutions per minute (give or take) Let me know if anyone picks any mistakes in my calculation. Gags Calc is ok, but measurement isn't. A 700C wheel is not 700mm diameter... it is 622mm and then there is the width of the tyre to add on. Put the calcs aside though: 45/16 up Burgandy St?!?!?! That's crazy talk! Ritch -- ritcho |
#3
|
|||
|
|||
Burgundy Street Climb on a fixed gear (Melb)
On 2008-02-05, ritcho (aka Bruce)
was almost, but not quite, entirely unlike tea: Gags Wrote: 50,000 m/h / 60 = 833.333 m/min 0.7m x pi = 2.199 m/revolution (for 700c wheel) 45 / 16 = 2.8125 wheel revolutions per pedal revolution 2.199 x 2.8125 = 6.185 m / pedal revolution 833.33 / 6.185 = 135 pedal revolutions per minute (give or take) Let me know if anyone picks any mistakes in my calculation. Gags Calc is ok, but measurement isn't. A 700C wheel is not 700mm diameter... it is 622mm and then there is the width of the tyre to add on. If I remember correctly, 25x700c is pretty darned close to 2000mm circumference, rolling. Which puts 45/16 at 70.5 gear inches. And 140rpm. Unless your speedo has 2100mm dialed into it, in which case the rpms are still good. P.S. Spin faster, bucko! I want 180rpm by next week! -- TimC Usage: fortune -P [-f] -a [xsz] Q: file [rKe9] -v6[+] file1 ... |
#4
|
|||
|
|||
Burgundy Street Climb on a fixed gear (Melb)
On Feb 5, 8:33 pm, TimC -
astro.swin.edu.au wrote: On 2008-02-05, ritcho (aka Bruce) was almost, but not quite, entirely unlike tea: Gags Wrote: 50,000 m/h / 60 = 833.333 m/min 0.7m x pi = 2.199 m/revolution (for 700c wheel) 45 / 16 = 2.8125 wheel revolutions per pedal revolution 2.199 x 2.8125 = 6.185 m / pedal revolution 833.33 / 6.185 = 135 pedal revolutions per minute (give or take) Let me know if anyone picks any mistakes in my calculation. Gags Calc is ok, but measurement isn't. A 700C wheel is not 700mm diameter... it is 622mm and then there is the width of the tyre to add on. If I remember correctly, 25x700c is pretty darned close to 2000mm circumference, rolling. Which puts 45/16 at 70.5 gear inches. And 140rpm. Unless your speedo has 2100mm dialed into it, in which case the rpms are still good. P.S. Spin faster, bucko! I want 180rpm by next week! -- TimC Usage: fortune -P [-f] -a [xsz] Q: file [rKe9] -v6[+] file1 ... You can calculate it all on Sheldon Brown's website ... sniff. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
FS: 58cm Fixed Gear - Gunnar Street Dog | [email protected] | Marketplace | 1 | February 26th 05 10:23 PM |
FS: 58cm Fixed Gear - Gunnar Street Dog | [email protected] | Marketplace | 0 | February 14th 05 02:17 PM |
FS: 58cm Gunnar Street Dog - Fixed Gear | [email protected] | Marketplace | 1 | February 11th 05 03:44 AM |
FS: 58 cm Gunnar Street Dog Fixed Gear | [email protected] | Marketplace | 0 | February 1st 05 02:40 AM |
How steep is the Burgundy Street climb? | blah | Australia | 19 | October 9th 04 09:37 AM |