Another stack/reach question
03-02-19, 03:53 PM
#26
Senior Member
Join Date: Oct 2015
Posts: 15,491
Bikes: 2015 Workswell 066, 2017 Workswell 093, 2014 Dawes Sheila, 1983 Cannondale 500, 1984 Raleigh Olympian, 2007 Cannondale Rize 4, 2017 Fuji Sportif 1 LE
Mentioned: 144 Post(s)
Tagged: 0 Thread(s)
Quoted: 7652 Post(s)
Liked 3,477 Times
in
1,836 Posts
So long as the OP is happy with the info in the thread, I am happy.
03-02-19, 04:51 PM
#27
Sage Member
Sorta related question.. is there any web-based calculator or app out there where I can plug in the known geometry sizes from an older bike (before stack and reach were more commonly available in geo charts), and it would be able to spit out the calculated stack and reach figures?
Stack and reach calculator
03-02-19, 05:14 PM
#28
Senior Member
Related, what's the stack:reach ratio at which point a bike shifts from a race geometry more to an endurance geometry?
03-02-19, 06:40 PM
#29
Senior Member
Join Date: Feb 2016
Location: SE Wisconsin
Posts: 1,851
Bikes: Lemond '01 Maillot Jaune, Lemond '02 Victoire, Lemond '03 Poprad, Lemond '03 Wayzata DB conv(Poprad), '79 AcerMex Windsor Carrera Professional(pur new), '88 GT Tequesta(pur new), '01 Bianchi Grizzly, 1993 Trek 970 DB conv, Trek 8900 DB conv
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 759 Post(s)
Likes: 0
Liked 810 Times
in
471 Posts
03-02-19, 10:53 PM
#31
Senior Member
Hi Guys,
I have a Titanium bike which is my best fitting bike. Stack 565, reach 377. Using 20mm of spacers [fat and old :-) ]
Looking at buying a new CF bike which has a stack of 585, reach 378.
Would I be right in assuming that they would fit identically, if I did not use spacers on my new bike?
I have a Titanium bike which is my best fitting bike. Stack 565, reach 377. Using 20mm of spacers [fat and old :-) ]
Looking at buying a new CF bike which has a stack of 585, reach 378.
Would I be right in assuming that they would fit identically, if I did not use spacers on my new bike?
03-02-19, 10:56 PM
#32
Senior Member
Actually, I think it's only possible that different forks will yield different angles (and hence a changed Reach/Stack). Ie. you could take the same bike, mount a fork with 40mm of rake, and another with 50mm of rake -- if they are the same length, the angles will be the same and neither reach or stack are affected.
03-03-19, 12:04 AM
#33
Senior Member
Thread Starter
I'm getting a new carbon bike, as my old carbon bike is fairly old, and am looking forward to trying out Di2. Just wanted to make sure that the fit would be reasonably similar. It's a mail order [Canyon].
03-03-19, 01:25 AM
#34
Senior Member
Join Date: Oct 2015
Posts: 15,491
Bikes: 2015 Workswell 066, 2017 Workswell 093, 2014 Dawes Sheila, 1983 Cannondale 500, 1984 Raleigh Olympian, 2007 Cannondale Rize 4, 2017 Fuji Sportif 1 LE
Mentioned: 144 Post(s)
Tagged: 0 Thread(s)
Quoted: 7652 Post(s)
Liked 3,477 Times
in
1,836 Posts
We await pics of the new ride.
03-03-19, 02:35 AM
#35
Senior Member
Thread Starter
It's going to be a while. I live in India, and ordering this to ride in my upcoming France trip, which will be on 18th Feb.
First, I hope that my airbnb host will be willing to accept and keep a bike for me, second, I hope that the bike remains in stock till she agrees, and finally, hope no disaster leads to cancellation of my trip. Complicated.
First, I hope that my airbnb host will be willing to accept and keep a bike for me, second, I hope that the bike remains in stock till she agrees, and finally, hope no disaster leads to cancellation of my trip. Complicated.
03-03-19, 06:57 AM
#36
Senior Member
Join Date: Feb 2016
Location: SE Wisconsin
Posts: 1,851
Bikes: Lemond '01 Maillot Jaune, Lemond '02 Victoire, Lemond '03 Poprad, Lemond '03 Wayzata DB conv(Poprad), '79 AcerMex Windsor Carrera Professional(pur new), '88 GT Tequesta(pur new), '01 Bianchi Grizzly, 1993 Trek 970 DB conv, Trek 8900 DB conv
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 759 Post(s)
Likes: 0
Liked 810 Times
in
471 Posts
Sorta like this, but for road bikes.
03-03-19, 07:04 AM
#37
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4735 Post(s)
Liked 1,532 Times
in
1,003 Posts
Axle-to-crown is another word for fork length apparently. So I'm saying if you have two forks, both with the same length (or A2C), then nothing changes in terms of angles, reach or stack.
03-03-19, 07:42 AM
#38
Senior Member
Thread Starter
Tire clearance doesn't matter unless you're comparing two bikes that only differ by the tires that were installed.
Axle-to-crown is another word for fork length apparently. So I'm saying if you have two forks, both with the same length (or A2C), then nothing changes in terms of angles, reach or stack.
Axle-to-crown is another word for fork length apparently. So I'm saying if you have two forks, both with the same length (or A2C), then nothing changes in terms of angles, reach or stack.
I have a road bike and a gravel bike, both with 16.2mm headtubes, but the stack is about 2.5cm more on the gravel bike.
03-03-19, 07:47 AM
#39
Senior Member
Thread Starter
Though, I still cannot wrap my head around how the fork affects it at all.
The measurement for stack is between BB and headtube, which will always be a constant irrespective of the fork length.
The measurement for stack is between BB and headtube, which will always be a constant irrespective of the fork length.
03-03-19, 07:56 AM
#40
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4735 Post(s)
Liked 1,532 Times
in
1,003 Posts
From sheldon:
03-03-19, 07:59 AM
#41
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4735 Post(s)
Liked 1,532 Times
in
1,003 Posts
I think what he means is that the newer disc brake bikes, have a taller fork, to allow for larger tyres, and that affects stack. Much as you have also explained.
I have a road bike and a gravel bike, both with 16.2mm headtubes, but the stack is about 2.5cm more on the gravel bike.
I have a road bike and a gravel bike, both with 16.2mm headtubes, but the stack is about 2.5cm more on the gravel bike.
And as you realized stack is measured from the BB, not the ground.
03-03-19, 07:59 AM
#42
Senior Member
Thread Starter
That's what I'm saying. The only way a fork can impact stack is if you're comparing 2 identical bikes but only the length of the fork differs. ie a longer fork would raise the front end (HT) of the bike higher off the ground a bit further than the BB would be raised.
From sheldon:
From sheldon:
03-03-19, 08:06 AM
#43
Senior Member
Thread Starter
03-03-19, 08:56 AM
#44
Perceptual Dullard
Join Date: Sep 2009
Posts: 2,421
Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 919 Post(s)
Liked 1,156 Times
in
494 Posts
Exactly. The rear dropout is part of a frame but not the front dropout -- that's part of the fork. That's why if you are only handed a frame and a tape measure and a plumb bob but no fork, you can't measure stack or reach. That's why it's kind of silly to worry about the final millimeter of stack and reach measurements -- choice of stem length and angle, choice of saddle and saddle position, choice of crank length can have much more effect on fit and comfort than a couple of mm of difference in stack and reach. Stack and reach puts you in the right ballpark, and helps you separate "tall and narrow" frames from "low and long" frames, and separate small, medium, and large frames. That all said, bikes are adjustable and people are adaptable. Enjoy your new bike.
03-03-19, 10:12 AM
#45
Senior Member
The biggest mistake that can be made when comparing two frames using reach and stack numbers is forgetting to make a correction to the reach when the stack heights are different.
If two frames have a large 20mm difference in stack, there will be an additional 6mm difference in reach between the two frames. I assume that the shorter frame would be set up with 20mm of spacer, which would reduce the reach by about 6mm, compared to the taller frame.
If two frames have a large 20mm difference in stack, there will be an additional 6mm difference in reach between the two frames. I assume that the shorter frame would be set up with 20mm of spacer, which would reduce the reach by about 6mm, compared to the taller frame.
03-03-19, 10:34 AM
#46
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4735 Post(s)
Liked 1,532 Times
in
1,003 Posts
The biggest mistake that can be made when comparing two frames using reach and stack numbers is forgetting to make a correction to the reach when the stack heights are different.
If two frames have a large 20mm difference in stack, there will be an additional 6mm difference in reach between the two frames. I assume that the shorter frame would be set up with 20mm of spacer, which would reduce the reach by about 6mm, compared to the taller frame.
If two frames have a large 20mm difference in stack, there will be an additional 6mm difference in reach between the two frames. I assume that the shorter frame would be set up with 20mm of spacer, which would reduce the reach by about 6mm, compared to the taller frame.
03-03-19, 10:48 AM
#47
Senior Member
You always have to consider all of the components that go into the fit, if you're buying a complete bike. I always buy a frame/fork and put the same components on it, as much as possible, so I know that the fit will be the same, or make a deliberate change to correct a known reach or stack difference.
Thread
Thread Starter
Forum
Replies
Last Post
milkbaby
Road Cycling
3
12-07-12 03:49 PM
