RoadBikeReview.com's Forum Archives - General


Archive Home >> General(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 )


new spreadsheet for gear/speed/rpm calcs(8 posts)

new spreadsheet for gear/speed/rpm calcsDougSloan
Feb 28, 2003 2:36 PM
I got tired of re-entering rpm numbers to see the resulting speeds, so I modified my Excel spreadsheet to have an input cell for speed, showing the resulting needed rpms to achieve that speed. Feel free to point out any errors or suggested changes.

You can download the spreadsheet here:

http://www.midcalracing.com/gears.xls

Thanks.

Doug
Heres what I've usedSprint-Nick
Feb 28, 2003 2:53 PM
Its not nearly as versatile as the one you posted but it is very simple. The gear and cadence are the ones that can be manipulates in the cadence vs speed calculator.

The website is: http://www.podiumbound.ca/misc/Track.xls <-make sure to capitalize the T.

Nick
PodiumBound.ca
that's goodDougSloan
Feb 28, 2003 2:55 PM
That's good, when you only have one gear on your bike. :-)

I like to see comparisons side by side, though, and do a lot of "what if's?".

BTW, what gears do you normal use for a match sprint?

Doug
GearsSprint-Nick
Feb 28, 2003 3:29 PM
I warned you it was what I used :)

For match sprint from memory I'd say I normally used an 88 inch gear in 2001. The thing is theres a couple ways to get an 88 inch gear. You can go 49-15 or 46-14. Since chainrings are made from about 44-52 for track. Either way it gives you a speed of about 61 km/h at 145 rpm and allows for a fast jump.

Either way since I will be a lot stronger this year I suspect my gears will have to be adjusted accordingly. I believe Ryan Bailey (Aussie sprinter who won commonwealth games) only used a 91 inch gear and a heck of a lot of leg speed to edge out Sean Easie (Aussie speinter who won world champs).

Nick
nice job Doug, I will use this one regularlybigrider
Mar 1, 2003 5:37 AM
I think the point you were making earlier about using the 11 really shows up when using this chart. If your cadence is 90 in the 11 cog with a 53 in the front you are going 31 mph. That is not just nice to have on long downhills but also on shorter sloping hills or if you have a great tailwind with a slight decline.

With all that said my riding preference (the one that meets my needs) is a 12-27 with a double up front. Saves me fron the triple and I only have to give up a little at the top end.
Doug, very helpful to me, thank you. nmSintesi
Mar 1, 2003 6:29 AM
re: new spreadsheet for gear/speed/rpm calcs4bykn
Mar 1, 2003 1:36 PM
Not much help for those of us without excel :(
sorry; thought BG got everyone :-) nmDougSloan
Mar 1, 2003 2:13 PM