Track Cycling: Velodrome Racing and Training Area Looking to enter into the realm of track racing? Want to share your experiences and tactics for riding on a velodrome? The Track Cycling forums is for you! Come in and discuss training/racing, equipment, and current track cycling events.

Gearing for scratch/points race?

Old 08-21-18, 04:03 AM
  #26  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by Divebrian View Post
Interesting....I know the amount will vary with speed, but at sprint speeds on a 250m track, how much different is the displayed GPS speed vs actual?
I guess the answer is...it depends. Depends on what their recording interval is mainly (eg 1 or 5s with a Garmin). For higher speeds, there would be a longer distance between record points than the straight line distance that GPS uses. On the straights there is really no difference

It wonít be much, and with Strava you can box in a section of data to get an average.
brawlo is offline  
Old 08-21-18, 04:08 AM
  #27  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
IMO I still stand by my bigger gear advice. You’re a strong guy, a good candidate, and if you are aiming for worlds, then you should be aiming to be smashing your local competition, not just hanging with them. You will need good fitness for that level and those enduro races will help
brawlo is offline  
Old 08-21-18, 02:26 PM
  #28  
Divebrian
Senior Member
Thread Starter
 
Join Date: Dec 2016
Posts: 160
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 115 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by brawlo View Post
IMO I still stand by my bigger gear advice. Youíre a strong guy, a good candidate, and if you are aiming for worlds, then you should be aiming to be smashing your local competition, not just hanging with them. You will need good fitness for that level and those enduro races will help

I'm a realist...just hanging with them is my goal. I'm sure there will be people there that participated in mass start events at Masters Nats last month and are training for mass start at Worlds in October. This is my first official mass start race in a long time and previously when I did them, I hadn't learned to be selfish and was always up front pushing the pace. I have now learned and understand the philosophy of being selfish, but don't know if I'll have the self control to implement it. I have no illusion of coming out for my first race and getting my gearing and tactics spot on.....if I get either of those two right, I'll consider it a success. I'm going more for the fitness aspect.....
Divebrian is offline  
Old 08-21-18, 02:47 PM
  #29  
carleton
Elitist
 
carleton's Avatar
 
Join Date: Jul 2005
Location: Atlanta, GA
Posts: 15,575
Mentioned: 82 Post(s)
Tagged: 0 Thread(s)
Quoted: 1206 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by Divebrian View Post
I'm a realist...just hanging with them is my goal. I'm sure there will be people there that participated in mass start events at Masters Nats last month and are training for mass start at Worlds in October. This is my first official mass start race in a long time and previously when I did them, I hadn't learned to be selfish and was always up front pushing the pace. I have now learned and understand the philosophy of being selfish, but don't know if I'll have the self control to implement it. I have no illusion of coming out for my first race and getting my gearing and tactics spot on.....if I get either of those two right, I'll consider it a success. I'm going more for the fitness aspect.....
Comfort. It all starts with comfort.

Comfort on the bike. Comfort on the particular track. Comfort with your bike handling. Comfort of your legs and lungs. All of that will come with time-on-task.

Once you are comfortable, your mind will stop worrying about those things and be free to strategize.

Also, many people focus on "trying to win". I like to think from the other perspective, "trying not to lose". If you note the few things that cause one to lose and address those, at the end of the race, you'll find yourself in a position to win...or be beaten. There is nothing wrong with being beaten by a better competitor. We always get down on ourselves for losing based on something we had control over.

Regarding GPS data:

It's booty for track data analysis. Zero data is better than GPS data for track efforts. Seriously. GPS data can simply be misleading. Misleadingly high values or misleadingly low values. RPE (Rated Perceived Exertion) could be a better metric than bad data.

What happens is that the speed is calculated based on your GPS location changes between satellite pings. So, if the satellite thinks your location changed 50 meters in 5 seconds, then that's 10 m/s (22 mph). The problem is...satellites are not accurate. Not as accurate as a magnet on your wheel tripping a speed sensor.

For example, if you look at maps of files from track efforts that used GPS, you'll see the rider teleporting across the track. That's because the signal dropped somehow. So, the head unit does a "best guess" and assumes that you rode a straight line from the back straight to the home straight (across the infield) instead of riding through turns 3 and 4. I thinks you made that trip slowly.

Anecdote: I used to have a Garmin 500. When my SRM was off for service, I used the Garmin to track speed and cadence during a day's workout. I was sitting in the infield between efforts with the bike leaning on the bench. The start/stop beep kept sounding off. Basically, the head unit thought the bike was moving a few mph as it stood still leaning against the bench. I looked at the screen and indeed it showed a speed value.

GPS is totally fine for long rides. But, if you are analyzing track efforts, you want to see as close to exact numbers as possible. You don't want to do a flying 200 and see a max speed of 20mph...or 60mph.

A $20 wired Cateye would seriously provide more value. Just remember to note your top speeds and reset between efforts. You can rest assured that that number is very accurate.
carleton is offline  
Old 08-21-18, 03:21 PM
  #30  
gl98115
Senior Member
 
Join Date: Apr 2014
Posts: 631
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 140 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Divebrian View Post
Interesting....I know the amount will vary with speed, but at sprint speeds on a 250m track, how much different is the displayed GPS speed vs actual?
I have an ANT+ speed sensor (magnet on wheel, not accelerometer based) on my track bike which takes care of any GPS issues.
gl98115 is offline  
Old 08-22-18, 10:26 PM
  #31  
colnago62
Senior Member
 
Join Date: Aug 2014
Posts: 1,401
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 259 Post(s)
Likes: 0
Liked 12 Times in 9 Posts
Originally Posted by brawlo View Post
IMO I still stand by my bigger gear advice. Youíre a strong guy, a good candidate, and if you are aiming for worlds, then you should be aiming to be smashing your local competition, not just hanging with them. You will need good fitness for that level and those enduro races will help
A few years ago now, Masters Nationals was at the Jerry Baker Velodrome. In the points race, I canít remember the age group, there was this rider that was consistently 1st across the line for every sprint. He than went out and took a lap. JBV is a 400 meter track, so taking a lap can be challenging. There some guys there who looked like they could hang with Cat 1/2 seniors.
colnago62 is offline  
Old 08-22-18, 10:46 PM
  #32  
Clythio
Senior Member
 
Join Date: Aug 2016
Posts: 85
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 50 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by colnago62 View Post


A few years ago now, Masters Nationals was at the Jerry Baker Velodrome. In the points race, I canít remember the age group, there was this rider that was consistently 1st across the line for every sprint. He than went out and took a lap. JBV is a 400 meter track, so taking a lap can be challenging. There some guys there who looked like they could hang with Cat 1/2 seniors.
One guy did the same at Master Worlds 2017 at Carson Velo... but it didn't end well... ;-) It was not a case of "the right gear", but the "wrong suplement", lets say.
Clythio is offline  
Old 08-22-18, 11:17 PM
  #33  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by Clythio View Post
One guy did the same at Master Worlds 2017 at Carson Velo... but it didn't end well... ;-) It was not a case of "the right gear", but the "wrong suplement", lets say.
When you go out and play those games, probably best not to go out and put a big target on your back
brawlo is offline  
Old 08-23-18, 11:36 AM
  #34  
carleton
Elitist
 
carleton's Avatar
 
Join Date: Jul 2005
Location: Atlanta, GA
Posts: 15,575
Mentioned: 82 Post(s)
Tagged: 0 Thread(s)
Quoted: 1206 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by brawlo View Post
When you go out and play those games, probably best not to go out and put a big target on your back
That video of his race will be used in WADA training sessions

Dude won every sprint. Lapped the field twice (leading and not drafting). Dropped the hangers-on who took the laps with him. Won the final sprint...all with a wind-catching, damn-near vertical riding position.

He moved through the field like an elite racing among 60 year olds.
carleton is offline  
Old 08-27-18, 02:22 AM
  #35  
bitingduck
Senior Member
 
bitingduck's Avatar
 
Join Date: Jan 2005
Posts: 3,165
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by carleton View Post
What happens is that the speed is calculated based on your GPS location changes between satellite pings. So, if the satellite thinks your location changed 50 meters in 5 seconds, then that's 10 m/s (22 mph). The problem is...satellites are not accurate. Not as accurate as a magnet on your wheel tripping a speed sensor.
The satellites are extremely accurate, it's how your Garmin decides to calculate your velocity that isn't. A GPS unit has to track the frequencies from all the satellites it's locked on very accurately, and those frequencies are known and very stable. They can use the doppler shift (which they get for free from having to track the frequencies) to get velocity to cm/s or better. GPS's for cycling don't do that because the typical user wants to know the average speed over some relatively long distance that took some relatively long time.
__________________
Track - the other off-road
http://www.lavelodrome.org
bitingduck is offline  
Old 08-27-18, 02:58 AM
  #36  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by bitingduck View Post
The satellites are extremely accurate, it's how your Garmin decides to calculate your velocity that isn't. A GPS unit has to track the frequencies from all the satellites it's locked on very accurately, and those frequencies are known and very stable. They can use the doppler shift (which they get for free from having to track the frequencies) to get velocity to cm/s or better. GPS's for cycling don't do that because the typical user wants to know the average speed over some relatively long distance that took some relatively long time.
The satellites are what they are, itís the calculation hardware in the unit that gives accurate positioning, particularly the clock. Atomic clocks small enough to fit inside a phone or even a Garmin have been around for years now. Those would enable accuracy to centimetres rather than the standard metres, but the consumer isnít willing to pay the extra for that level of accuracy. A speed sensor is a whole lot cheaper
brawlo is offline  
Old 08-27-18, 03:31 AM
  #37  
bitingduck
Senior Member
 
bitingduck's Avatar
 
Join Date: Jan 2005
Posts: 3,165
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by brawlo View Post
The satellites are what they are, itís the calculation hardware in the unit that gives accurate positioning, particularly the clock. Atomic clocks small enough to fit inside a phone or even a Garmin have been around for years now. Those would enable accuracy to centimetres rather than the standard metres, but the consumer isnít willing to pay the extra for that level of accuracy. A speed sensor is a whole lot cheaper
You don't need an atomic clock to do it - the velocity measurement is just a doppler shift measurement, and it's one that every GPS (including cheap ones) has to do in order to lock on the satellite signals. Consumer-priced GPS units could do it if people wanted it - there are ~20 year old publications of people doing ~cm/s accuracy with cheap consumer grade GPS units. A magnet and a frequency counter are a lot cheaper, but given the large numbers of expensive GPS units I see on bikes, it wouldn't be unreasonable to expect it from GPS units. I really just wanted to address the suggestion that GPS speed is intrinsically inaccurate (that Carleton implied) - even consumer grade GPS *can* give very accurate speed, they just aren't sold with that feature for cyclists.
__________________
Track - the other off-road
http://www.lavelodrome.org
bitingduck is offline  
Old 08-27-18, 09:44 AM
  #38  
carleton
Elitist
 
carleton's Avatar
 
Join Date: Jul 2005
Location: Atlanta, GA
Posts: 15,575
Mentioned: 82 Post(s)
Tagged: 0 Thread(s)
Quoted: 1206 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Thanks for the correction and education, bitingduck and brawlo!

Is battery power one reason why the devices aren't configured to record more accurately? Internal memory?
carleton is offline  
Old 08-27-18, 02:43 PM
  #39  
Divebrian
Senior Member
Thread Starter
 
Join Date: Dec 2016
Posts: 160
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 115 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks to those that responded, turned out that 52/14 or 51/14 were the correct gears for me this weekend, it was a combined field of 18, all Master men and Open women.....did the 1st race on a 52/14, felt good, had plenty of power but wondered if I was over geared, dropped down to a 50/14 for the next race and had to stay in a higher rpm range than I prefer, did the 3rd and 4th races on a 51/14 and at times, it left me wishing I had the 52/14. I'm more of a diesel engine than a high revving 4 cylinder.....


And a special thanks to topflightpro for taking the time to personally show me around the velodrome on Sunday and proving that 50/14 was too small of a gear.
Divebrian is offline  
Old 08-27-18, 03:25 PM
  #40  
tobukog
Senior Member
 
Join Date: Jul 2016
Posts: 187
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 95 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Divebrian View Post
Thanks to those that responded, turned out that 52/14 or 51/14 were the correct gears for me this weekend, it was a combined field of 18, all Master men and Open women.....did the 1st race on a 52/14, felt good, had plenty of power but wondered if I was over geared, dropped down to a 50/14 for the next race and had to stay in a higher rpm range than I prefer, did the 3rd and 4th races on a 51/14 and at times, it left me wishing I had the 52/14. I'm more of a diesel engine than a high revving 4 cylinder.....


And a special thanks to topflightpro for taking the time to personally show me around the velodrome on Sunday and proving that 50/14 was too small of a gear.
Hey, were you the guy with the cart? If so, I think you did great in getting back into mass start racing. I'm always amazed that gearing is such a strange thing -- the difference between a 51 and a 52 14 is about 2%, or perhaps~ 2rpm. That's 2 extra rotations spread out over a whole minute. Yet it can be the difference between feeling comfortable and feeling bogged down or spun out.
tobukog is offline  
Old 08-27-18, 04:19 PM
  #41  
Divebrian
Senior Member
Thread Starter
 
Join Date: Dec 2016
Posts: 160
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 115 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Yep, that's me...we're you one of the 40 yr olds that always seemed to have energy for one lap more than me?
Divebrian is offline  
Old 08-27-18, 06:05 PM
  #42  
tobukog
Senior Member
 
Join Date: Jul 2016
Posts: 187
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 95 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Divebrian View Post
Yep, that's me...we're you one of the 40 yr olds that always seemed to have energy for one lap more than me?
I was the Asian guy with his mess spread out next to your cart who was coughing and dry heaving into the grass after every race. I didn't race Saturday -- I had promised my team mate that we'd go up to Tennessee instead. It was a LONG weekend.
tobukog is offline  
Old 08-27-18, 06:26 PM
  #43  
bitingduck
Senior Member
 
bitingduck's Avatar
 
Join Date: Jan 2005
Posts: 3,165
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by carleton View Post
Is battery power one reason why the devices aren't configured to record more accurately? Internal memory?
I suspect it's lack of user demand.
__________________
Track - the other off-road
http://www.lavelodrome.org
bitingduck is offline  
Old 08-28-18, 04:18 AM
  #44  
topflightpro
Senior Member
 
topflightpro's Avatar
 
Join Date: Jul 2007
Posts: 6,283
Mentioned: 44 Post(s)
Tagged: 0 Thread(s)
Quoted: 1236 Post(s)
Liked 25 Times in 19 Posts
I'm surprised to read GPS has such accurate technology. I was reading an article about autonomous cars and one of the technology challenges was the lack of accuracy of GPS systems - they were good to pinpoint vehicle locations within a few feet, which isn't accurate enough to prevent crashes.
topflightpro is offline  
Old 08-28-18, 04:57 AM
  #45  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by bitingduck View Post
You don't need an atomic clock to do it - the velocity measurement is just a doppler shift measurement, and it's one that every GPS (including cheap ones) has to do in order to lock on the satellite signals. Consumer-priced GPS units could do it if people wanted it - there are ~20 year old publications of people doing ~cm/s accuracy with cheap consumer grade GPS units. A magnet and a frequency counter are a lot cheaper, but given the large numbers of expensive GPS units I see on bikes, it wouldn't be unreasonable to expect it from GPS units. I really just wanted to address the suggestion that GPS speed is intrinsically inaccurate (that Carleton implied) - even consumer grade GPS *can* give very accurate speed, they just aren't sold with that feature for cyclists.
Saying you have an accurate position and actually having an accurate position are 2 different things. If it were really that easy, a whole lot of companies would already be well and truly all over it. Iím a surveyor by trade and we deal in accuracy. Cheap single receiver systems just donít give that accuracy to you. Theyíre only accurate to a few metres despite what they may tell you. The key component was/is the clock. Their use can get a single receiver accurate to within a few cm. But theyíre expensive.

Originally Posted by carleton View Post
Thanks for the correction and education, bitingduck and brawlo!

Is battery power one reason why the devices aren't configured to record more accurately? Internal memory?
Cost is key
brawlo is offline  
Old 08-28-18, 05:03 AM
  #46  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by topflightpro View Post
I'm surprised to read GPS has such accurate technology. I was reading an article about autonomous cars and one of the technology challenges was the lack of accuracy of GPS systems - they were good to pinpoint vehicle locations within a few feet, which isn't accurate enough to prevent crashes.
The raw accuracy component is available. A big problem in the use for cars is called multi pathing where signals are reflected off buildings and other large objects. You may have suffered from this when using a car GPS. Sometimes your location can be a bit strange or the signal just gets blocked altogether. The last I heard, scanning was what was proposed to overcome this issue when GPS goes awry
brawlo is offline  
Old 08-28-18, 08:35 AM
  #47  
bitingduck
Senior Member
 
bitingduck's Avatar
 
Join Date: Jan 2005
Posts: 3,165
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by brawlo View Post
Saying you have an accurate position and actually having an accurate position are 2 different things. If it were really that easy, a whole lot of companies would already be well and truly all over it. Iím a surveyor by trade and we deal in accuracy. Cheap single receiver systems just donít give that accuracy to you. Theyíre only accurate to a few metres despite what they may tell you. The key component was/is the clock. Their use can get a single receiver accurate to within a few cm. But theyíre expensive.
You don't need accurate position to get accurate velocity. A police radar doesn't know where you are at all, but when used along line of sight can give accurate velocity with no position information via the doppler effect. All you need is the frequency shift from each satellite and the direction to each satellite, and you can tolerate relatively large position errors because the satellites are far away so the angular error is very small. In order to even get the signal from each satellite any GPS receiver has phase locked loops (PLLs) that it has to adjust in frequency to match the doppler shifted signal from each of the satellites. That frequency deviation gives you the velocity along the line to each satellite. The GPS receiver knows where each satellite is in the sky, so a little bit of vector arithmetic gives you the instantaneous velocity. Many consumer GPS units do already use a variation of this to measure velocity, where they use the phase shift from measurement to measurement to extract velocity (somewhat less accurate, but better than differencing successive positions), but it can also be done in a similar cost single-frequency GPS using the doppler shift that the PLL is tracking. It's more useful to self-driving car makers than for cyclists.
__________________
Track - the other off-road
http://www.lavelodrome.org
bitingduck is offline  
Old 08-28-18, 03:30 PM
  #48  
brawlo
Senior Member
 
brawlo's Avatar
 
Join Date: Apr 2011
Location: Australia
Posts: 1,018
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 215 Post(s)
Liked 3 Times in 3 Posts
Originally Posted by bitingduck View Post
You don't need accurate position to get accurate velocity. A police radar doesn't know where you are at all, but when used along line of sight can give accurate velocity with no position information via the doppler effect. All you need is the frequency shift from each satellite and the direction to each satellite, and you can tolerate relatively large position errors because the satellites are far away so the angular error is very small. In order to even get the signal from each satellite any GPS receiver has phase locked loops (PLLs) that it has to adjust in frequency to match the doppler shifted signal from each of the satellites. That frequency deviation gives you the velocity along the line to each satellite. The GPS receiver knows where each satellite is in the sky, so a little bit of vector arithmetic gives you the instantaneous velocity. Many consumer GPS units do already use a variation of this to measure velocity, where they use the phase shift from measurement to measurement to extract velocity (somewhat less accurate, but better than differencing successive positions), but it can also be done in a similar cost single-frequency GPS using the doppler shift that the PLL is tracking. It's more useful to self-driving car makers than for cyclists.
My apologies, my brain was going elsewhere late last night. My guess is that Garmin at least must use doppler shift in its calculations. Given the inaccuracy of single receiver position measurement and thinking about low speed cycling and walking/running using position based velocity would make things look crazy. Thereís no info (read proprietary secret squirrel stuff) on how Garmin actually calculates velocity, but thereís a lot of chatter of Garmin not equaling Strava which just uses position based from uploaded data, unless you turn the GPS function off
brawlo is offline  
Old 09-09-18, 09:52 AM
  #49  
krispenhartung
Senior Member
 
krispenhartung's Avatar
 
Join Date: Dec 2014
Location: Boise, ID
Posts: 231

Bikes: S-Works Venge Dura-Ace DI2, KTM Strada 4000, Fuji Norcom Straight 1.3 (TT), Fuji Track Elite, BMC Trackmachine TR02

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 98 Post(s)
Likes: 0
Liked 2 Times in 1 Post
I wasn't sure where to put this, or if it would even be useful to anyone besides myself, but here it is. I can send anyone the source spreadsheet as well.
I created a custom spreadsheet gearing chart, which shows the range of gearing options incrementally from low to high vs. plotted in a matrix with cogs and chain rings on the x and y axes. This made it easier for me to develop a gear changing strategy, also allowing me to filter on a particular cog or chain ring size if I was attempting to stay with one cog, for instance. You can see the Velodrome Shopís gearing chart here for reference and comparison. I used 54 as the largest chain ring and 13 as the smallest cog. I could easily go higher or lower by adding new rows.
K-

krispenhartung is offline  
Old 09-09-18, 08:11 PM
  #50  
carleton
Elitist
 
carleton's Avatar
 
Join Date: Jul 2005
Location: Atlanta, GA
Posts: 15,575
Mentioned: 82 Post(s)
Tagged: 0 Thread(s)
Quoted: 1206 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
On a related note, if you are an iPhone user, I've created a free app where you input your inventory of chainrings and cogs (for road or track bikes) and your target gearing, it will output how to make that gear using what you have on hand.

I call it a "Reverse Gear Calculator":


I also provide a standard gear calculator:


All outputs are gear-inches, gear-meters, or ratio (chainring/cog).

FREE:
https://itunes.apple.com/us/app/trac...or/id925659197

I made this because I was tired of using gear charts
carleton is offline  

Thread Tools
Search this Thread

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

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.