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Thread: bikes getting longer, I am not getting taller

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    Default bikes getting longer, I am not getting taller

    I am studying Lee McCormack's method of fitting, getting body in shape, and practicing skills right now. (Just exploring ideas for science' sake.) His main point about bike fit is that the only thing that matters in the end is the distance from the rider's feet to the grips. He calls this RAD or Rider Area Distance. There is more than one way to achieve your RAD that results in a more upright position for gravity-oriented riders, low position for XC racers, and some options in between. I have heard others call it "room" or "effective downtube" (maybe I made that last one up).

    He has a simple calculator to determine your ideal RAD and another to help you figure out how to get there by means of stem and handlebar dimensions. These result in what I would call "effective reach" and "effective stack" because it tells the whole story about where your grips end up relative to the BB. Geometrically, RAD is the hypotenuse of a triangle formed from your effective reach and effective stack. I imagine the calculator has some formulas behind it built upon averages based on a huge database he has of previous riders' dimensions.

    He gives some advice about saddle position, but saddle position take a back seat (har har!) to getting your hands in a position that maximizes range of motion and stability relative to where your feet are. I agree with this concept because most other methods I have read focus on your sitting position on a trainer, which is useless as soon as the bike is leaned over or pointed up or down any sort of slope. He as a more complex calculator that takes into account non-average body proportions (aberrations in arm and leg length, mostly), but the standard calculator worked for me.

    At 174 mm tall (5’ 8.5”), my current bike (medium rigid Vassago Jabberwocky, 438 mm reach, 599 mm stack, 50mm stem) is set up a bit long for me by the LLB method. I am getting a 12-degree SQLabs 30X bar, which is lower, wider bar with more sweep (and added grip area setback from the center of the bar) and maybe dropping my stem another 5 mm. I am also borrowing a 35 mm stem to get RAD so I can get rad. Or something. I wanted a different handlebar anyway, and the stem is on loan, so this experiment is not costing me any extra money.

    The problem I am having with his approach is that it ends up telling almost everyone that their bike is “too long” and that they need to size down on frame sizes and use the shortest stem possible. I tried plugging in the geo from about a dozen bikes (yeah, there’s a nerdy spreadsheet) and I could only get my RAD right with mostly "small" frames and very, very short stems. For several models, I can only get their small frames to fit me with a slammed, low-angled, short stem, and riding a medium would be out of the question if I want to get that RAD measurement right.

    TLDR: frames are getting longer. Riders are not getting taller. Is the effective reach and stack (from BB to grips) staying the same on a bike that fits well over the years, or are people on bigger bikes really riding with their bodies in a less hinged position? I am just looking for a relevant counterpoint from someone with experience building bikes to fit riders to this method of fitting. It seems that one of the following is true: the LLB calculator is a bit off in some way, or bike manufacturers are doing us a disservice by making bikes with longer reach measurements.
    Jonathan - Austin, TX
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    Default Re: bikes getting longer, I am not getting taller

    Bikes are getting longer so you have more room standing up and a longer front center for downhill and can move your weight around. Top tubes are being kept reasonable using a steeper seat angle. This is a benefit for descending but not so much for flat twisty trails. The formula supposes riding in a specific manner that may or may not match how you ride. Also note for a given reach is specified at a given stack, increasing the stack reduces effective reach.

    As a tall guy I can't wait until I can justify a 500mm reach bike for technical trails with a 40-50mm stem but am happy on a 430mm reach bike with a 100 stem on flat twisty trails.
     

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    Default Re: bikes getting longer, I am not getting taller

    Mountain bikes have changed

    Easy way to think about it is distance between the wheels. As you go faster over rougher terrain you will start to deflect the wheels laterally. The longer the wheelbase the less 4inches of deflection matters considering rotation from the center of the bike. Bars are wider, stems are shorter. Bars are wider because it takes far less effort to stop your hands from being deflected.

    On steep rough terrain reach makes a shorter travel bike feel more capable. Your fitting system has not kept up.

    More than anything your local trails matter. What are you fitting people to? Are they going to Squamish, and need something to inspire confidence? Alternatively, are they riding faster twisty trails and need a shorter bike to get around switchbacks.

    My bike is very long. I run a 60mm stem with 800mm bars, stack of 645mm, and a reach of 510mm. I also have a fairly slack seat tube angle a hair under 74degrees. I am tall, but the bike was built to descend unlike a normal hardtail.

    My final comment would be to ride a modern forward geo bike. Understand what changed so you can explain that to your customers
     

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    Default Re: bikes getting longer, I am not getting taller

    The RAD system kinda sounds like BS to me. I agree with Andrew, local trails and your riding style mater a LOT with fitting MTBs, you can't simply plug numbers into a formula.

    I've got a Jabberwocky too (a "vintage" '09 model), and they're longer than most. Or at least, a few years ago they were, it's been a while since I've really looked at geometry charts for MTBs as I haven't been in the market for one.

    I'm 5'10", medium frame (which last I looked fit like a large on most other brands), 100mm stem, 685mm wide bar. Thomson setback post with the saddle slammed as far back as it'll go.

    I know...100mm stem on a MTB, 'narrow' 685mm bars - it sounds ancient. But for me it works - I like being leaned over a bit with some weight on the front wheel, makes it stick and go 'round corners a lot better for me. The bars were wider, but literally barely fit between the trees on some trails - I'm talking high speed stuff where if you centered it up perfectly you'd have 1/2" of free space on each end of the bar. That ain't enough room for me.

    I can't stand bikes with a short cockpit and long slack front end, I can't get enough weight on the front tire and they under steer like a Camry (for me). I'm sure they're super fun on long downhills, but for anything else I don't see the appeal.

    Anyhow, I love the way I fit this bike. I've done plenty of 6+ hour rides on it, so comfort is obviously pretty good. I do wish the rear end was a bit shorter, but that's about my only complaint.



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    Default Re: bikes getting longer, I am not getting taller



    Quote Originally Posted by mack_turtle View Post
    I am studying Lee McCormack's method of fitting, getting body in shape, and practicing skills right now. (Just exploring ideas for science' sake.) His main point about bike fit is that the only thing that matters in the end is the distance from the rider's feet to the grips. He calls this RAD or Rider Area Distance.
    Quote Originally Posted by mack_turtle View Post
    TLDR: frames are getting longer. Riders are not getting taller. Is the effective reach and stack (from BB to grips) staying the same on a bike that fits well over the years, or are people on bigger bikes really riding with their bodies in a less hinged position? I am just looking for a relevant counterpoint from someone with experience building bikes to fit riders to this method of fitting. It seems that one of the following is true: the LLB calculator is a bit off in some way, or bike manufacturers are doing us a disservice by making bikes with longer reach measurements.
    You know, I read something about this and my own opinion is that a measurement from feet to hands on the bike is the result of other measurements that are far more meaningful to determine fit. IMO: The most important measurement is the tip of the saddle to the center of the handlebars. Reach and Stack are industries way of giving consumers digestible numbers that they can compare to their own current bicycle and get an idea of how that bike compares with one they're thinking of purchasing. Fit formulae and science? There's no equation where you input data and the ideal frame pops out on the other end. These calculations are great ways to get you started or get you in a ballpark, but when it comes down to it, trial, error along with an experienced shop tech who can observe you ON the bike will enable you to fine-tune your fit. It took me several prototypes to nail my cockpit length, to be honest (which saddle tip to bar with saddle centered on the rails is 22" exactly). Everything else can move around between those locked in parameters when terrain and application are taken into account to determine appropriate geometry.

    Bikes getting longer: Longer top tubes paired with shorter stems, lengthen the wheelbase. But what is missing is that the cockpit measurements have remained the same. For every 10mm of stem you remove, you add approximately .5" of wheelbase and the front wheel moves physically forward. Combine this with a dropper and when you head downhill or are tackling tech, you are now more centered and IN the bike. Your weight is balanced between the wheels and you're able to "load/compress" both front and rear wheels to increase traction and carve harder through turns. The trick is finding that balance as a designer where you maintain all the performance attributes for the bikes intended use while layering on stability, control, traction and the bike remains quick, nimble and snappy. Some bikes are biased towards going downhill, while others are more XC oriented. Then there are bikes all over the spectrum.

    Me? I try and build "mountain bikes" which are very versatile that climb, descend and do everything in between exceedingly well. That's what I like to ride, so that is what I pursue when I go back to the drawing board.
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    Default Re: bikes getting longer, I am not getting taller

    I am of the opinion that saddle position is important for seated pedaling, but it can be a red herring. it's not as important as the relationship of your hands and feet when it comes to wrangling a mountain bike. saddle position has little to do with how your bike fits when you flip that dropper remote on your mtb, or on a BMX bike that has the saddle basically on top of the top tube by your knees. (yes, the RAD theory is applied the same way to BMX bikes.) I came to this conclusion on my own a long time ago, so that is why the RAD theory appeals to me- it's for wranglin, not ramblin.

    I found that the measurements I get are shorter than what I know is comfortable in a trainer or a flat, dirt road, but I need to test the theory on the trail. the reach he prescribes gives me a fit that, in my head for the moment, sounds too tight. that could also be a result of a lack of strength and flexibility, but you need to account for that too.

    it's not that big a jump though. for my frame with a relatively long reach, it's mostly a matter of stem length, with a little bit of an option for fudging the hand position around with rise and sweep. I think it would be possible to get my bike to fit with an 80mm stem or a 35mm stem.

    Quote Originally Posted by sailor View Post
    Bikes are getting longer so you have more room standing up and a longer front center for downhill and can move your weight around. Top tubes are being kept reasonable using a steeper seat angle. This is a benefit for descending but not so much for flat twisty trails. The formula supposes riding in a specific manner that may or may not match how you ride. Also note for a given reach is specified at a given stack, increasing the stack reduces effective reach.
    The calculator gives four options for riding styles, so it gives a range of effective reach/stack (horizontal/ vertical distance from BB to grips, not the handlebar clamp). The "gravity" option has more stack and less reach, while the "XC" options is the opposite, with a range in between. what remains the same for each rider, based on your sex, height, crank arm length, and pedal/shoe thickness, is the hypotenuse of those two measurements. he provides a maximum handlebar width, so everything else is based on that width can can presumably allow for a little fudging of the other measurements if you deviate from that width by more than a few cm. he says that a narrower handlebar width only has a marginal affect, so it's not in the calculator.

    The range of numbers it spits out also takes into account specific handlebar rise, setback (horizontal distance from bar clamp to grip area, the result of backsweep and width), stem/headset/spacer stack, headtube angle, and stem angle. the number represents the distance to your grips, since handlebar backsweep and rise can vary so much. it allows you to change those variables until you get something within the prescribed range of effective reach and stack.

    Quote Originally Posted by andrew flowers View Post
    Mountain bikes have changed

    My final comment would be to ride a modern forward geo bike. Understand what changed so you can explain that to your customers
    my only customer at this point is myself, but point taken. otherwise, see above. do "forward geometry" bikes actually have reach and stack ratios that put a rider's hands further away from their feet than previous bikes?

    Quote Originally Posted by dgaddis View Post
    The RAD system kinda sounds like BS to me. I agree with Andrew, local trails and your riding style mater a LOT with fitting MTBs, you can't simply plug numbers into a formula.

    I've got a Jabberwocky too (a "vintage" '09 model), and they're longer than most. Or at least, a few years ago they were, it's been a while since I've really looked at geometry charts for MTBs as I haven't been in the market for one.

    I'm 5'10", medium frame (which last I looked fit like a large on most other brands), 100mm stem, 685mm wide bar. Thomson setback post with the saddle slammed as far back as it'll go.



    I can't stand bikes with a short cockpit and long slack front end, I can't get enough weight on the front tire and they under steer like a Camry (for me). I'm sure they're super fun on long downhills, but for anything else I don't see the appeal.
    I bought my Jabber specifically because it's longer than most other bikes at the time and I felt "scrunched" on other bikes. However, now that I look at the numbers as a ratio of reach and stack, the Jabber is not a whole lot longer than most modern XC frames. it was ahead of its time in that it has more reach for it's stack than most similar bikes. yeah, i have a spreadsheet that proves that. if I had more complete information, I'd like to try plugging it into the calculator, (for science!) to see how far off your fit might be from it. I'll have to find the old Jabber geometry for that, because the new one has changed, but not by much. the new one has a shorter CS, btw.

    my riding style sounds similar to yours. not enough downhill where I live to want to "slack" bike for that kind of thing. everything here is like picking your way through a maze of rocks and trees. I enjoy the wider bars though.

    Quote Originally Posted by fortyfour View Post
    Me? I try and build "mountain bikes" which are very versatile that climb, descend and do everything in between exceedingly well. That's what I like to ride, so that is what I pursue when I go back to the drawing board.
    I'd be curious to see if there is any sort of correlation between the ratio of reach and stack that ends up on bikes you design for any particular riding style for a given rider height. I think that more accurately describes the theory. I'll have a cockpit set up like the one the calculator recommends next week and I'll report back.
    Jonathan - Austin, TX
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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by mack_turtle View Post
    I bought my Jabber specifically because it's longer than most other bikes at the time and I felt "scrunched" on other bikes. However, now that I look at the numbers as a ratio of reach and stack, the Jabber is not a whole lot longer than most modern XC frames. it was ahead of its time in that it has more reach for it's stack than most similar bikes. yeah, i have a spreadsheet that proves that. if I had more complete information, I'd like to try plugging it into the calculator, (for science!) to see how far off your fit might be from it. I'll have to find the old Jabber geometry for that, because the new one has changed, but not by much. the new one has a shorter CS, btw.
    The effective TT I don't think has changed. Good to see that the CS have shortened up!

    Old geometry chart here ::



    (found here :: Cycle Progression - Turner Frame Selection the frame shown is the version before mine, mind doesn't have the big gusset at the DT/HT junction)
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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by mack_turtle View Post
    I am of the opinion that saddle position is important for seated pedaling, but it can be a red herring. it's not as important as the relationship of your hands and feet when it comes to wrangling a mountain bike. saddle position has little to do with how your bike fits when you flip that dropper remote on your mtb, or on a BMX bike that has the saddle basically on top of the top tube by your knees. (yes, the RAD theory is applied the same way to BMX bikes.) I came to this conclusion on my own a long time ago, so that is why the RAD theory appeals to me- it's for wranglin, not ramblin.

    I found that the measurements I get are shorter than what I know is comfortable in a trainer or a flat, dirt road, but I need to test the theory on the trail. the reach he prescribes gives me a fit that, in my head for the moment, sounds too tight. that could also be a result of a lack of strength and flexibility, but you need to account for that too.
    The way I fit/size a bike is when you are seated, taking sag into account. You're very dynamic on a mountain bike when out of the saddle. With it dropped, where the saddle is starts to lose importance other than to pinch or lean on to help guide the bike through turns. I've never mentally considered my hand/foot relationship. Where my center of gravity is however or rather my core? That is moving constantly in space and I'm paying close attention to where that is in relationship to the bike. Honestly if the above method nails your fit for you, and that's the way that helps you achieve a proper fit, then that's great. But I am admittedly not all that psyched on it.

    I never consider reach and stack and only provide it if the rider specifically asks for it. The distance from center of bottom bracket to top of saddle and saddle tip to handlebar center. Those two measurements, and a 3rd which is saddle tip to center of saddle/seatpost head connection, are the most important ones for me to triangulate a rider on a bike. But the nuance comes from looking at where the saddle would sit in space in relation to the handlebars, so I am often bringing handlebars up or down in space. Geometry in this order of importance: Head tube angle, bottom bracket drop, chainstay length. Those 3 working together determines how the bike will perform once it's "fit" is determined for the rider. Every tube then connects these dots. Stem length also is fine tuned depending on terrain and riding style of the rider (and in some cases height/inseam) It's finding the right balance of geometry characteristics based on the riders preference and terrain and then it becomes my job to fine tune the performance attributes that are appropriate for that rider. No one number is king. It's a combination of a bunch of factors.

    Quote Originally Posted by mack_turtle View Post
    it's not that big a jump though. for my frame with a relatively long reach, it's mostly a matter of stem length, with a little bit of an option for fudging the hand position around with rise and sweep. I think it would be possible to get my bike to fit with an 80mm stem or a 35mm stem.
    Good luck!
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    Default Re: bikes getting longer, I am not getting taller

    one question for Kris: when you're looking at those three dimensions, is that mostly for designing a frame with custom geometry, or for making a stock bike fit a rider? is that method equally useful for both?

    interesting stuff. I think it's fair to say that this calculator just makes bikes fit with a shorter overall reach than most people are used to. still not sure if that's some revolutionary new way of fitting bikes or an imprudent way of making bikes fit in a way that suits certain riders on a certain kind of terrain.

    for my medium Jabberwocky with a 70 HA and 615mm ETT for a 174 cm rider, RAD demands that I use a low handlebar and a slammed stem no longer than 50mm for the "XC fit". if I wanted to use the "trail fit" I would need an impossibly short stem. In the end, I think that makes sense since I am at the low end of personal height for this frame. It's an XC frame, if it can be categorized at all anyways, so what's the point of trying to force it into something it's not. I could probably have purchased the small frame and used a ton of seatpost and a longer stem, or the medium with a shorter stem and no so much seatpost. I'd rather have the latter for how I want to ride. I'll have to try the new lower, wider handlebar I am getting with a few stems I have in 50-90mm lengths just to see how it works out. that 35 I was going to borrow turned out to be a 50, which I already have.

    this brings up an interesting question for me: with modern XC/ trail bikes that have slightly longer reaches than years past, slacker HAs in the 68-70 degrees, and are genrally being riden with wider bars, at what point is a stem "too short" for the sake of handling on technical trails? is there any sort of useful generalizations about head tube angles and stem lengths? bar width and stem length?

    someone pointed out to me that a <50mm stem on a frame with a head tube that steep would adversely affect the handling due to the relationship between the stem and the fork trail. I have yet to wrap my head around fork trail, but a 480mm A-C rigid fork with a 45mm offset might be daft.
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    Default Re: bikes getting longer, I am not getting taller

    I would listen to the logic presented by dgaddis and 44 vs. what Lee McCormack is preaching.

    The problem I see with modern bikes with longer reach is this- They are designed to be used with a short stem by a normal to longer reach rider- This leaves a rider who doesn't need long reach with a bike that is way too long- even with an uber short stem.
    What do you do? Flip the stem so it faces backwards?
    Also- bikes seem to be getting shorter and shorter in terms of stack.

    Make bikes so normal size riders need a 90-100mm stem. Those who need shorter can go shorter, those who need to be longer can go longer.
     

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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by boots2000 View Post
    Make bikes so normal size riders need a 90-100mm stem. Those who need shorter can go shorter, those who need to be longer can go longer.
    I really don't see that happening any time soon. You sound like a dirt roadie. :wink:
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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by boots2000 View Post
    I would listen to the logic presented by dgaddis and 44 vs. what Lee McCormack is preaching.

    The problem I see with modern bikes with longer reach is this- They are designed to be used with a short stem by a normal to longer reach rider- This leaves a rider who doesn't need long reach with a bike that is way too long- even with an uber short stem.
    What do you do? Flip the stem so it faces backwards?
    Also- bikes seem to be getting shorter and shorter in terms of stack.

    Make bikes so normal size riders need a 90-100mm stem. Those who need shorter can go shorter, those who need to be longer can go longer.
    nah, adjust bar width not stem length in this case
     

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    Default Re: bikes getting longer, I am not getting taller

    The "Industry" has decreed that everyone needs to ride a Mountain Chopper whereas this is not the case.


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    Default Re: bikes getting longer, I am not getting taller

    I am aware that there's no fix-all forumla that can predict what will provide the most handling confidence on any sort of bike, terrain, or rider. but I would like to know if anyone has compiled enough data to extract any generalizations about how these three interact with one another.

    perahps the question could be addressed logically by asking:

    • given the same handlbar width and stem length, slackening the headtube should do ___ to the handling.
    • given the same HA and bar width, shortening the stem ought to do ___ to the handling.
    • given the same stem length and HA, widening the bar should do ___ to the handling.


    in that vein, hands relative to steering axis? is there any correlation between how far in front of (think road bike, long stem MTB) or behind (beach cruiser) your hands end up behind the steering axis?

    this topic was on my mind becauseI wanted to experiment with an even shorter stem but LBS dude told me that a bike with a 70 degree head tube angle should not be used with a stem shorter than 70mm due to fork trail. I've never gotten my head around trail. I am all for a nerdy discussion on the topic but I can't find anything. I am pretty sure that a 50mm stem on this bike is shorter than necessary and might be hurting my body and riding, but it's been an interesting experiement.
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    Default Re: bikes getting longer, I am not getting taller

    Stems are pretty cheap. Try it, see if you like it. I don't know your mechanic, but most mechanics don't know diddly about trail (I'll be honest - I know only slightly more than diddly). That statement sounds like a generalization he heard at some point, but who knows why or when it applies (to road bikes? 26" MTBs with non suspension corrected forks?).

    Also, if you wanna go really short on the stem, y'all seen the Pacenti P-dent stuff? You can only shorten the stem so much before the bars hit the steerer tube, well the P-dent bars have a 'dented' bar to fit around the steerer a bit.

    Review: Pacenti PDent Handlebar and Stem - Pinkbike
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    Default Re: bikes getting longer, I am not getting taller

    Come ride with me and see-
    If a dirt roadie wears lycra, no visor, uses clipless pedals, and doesnt show up for a ride with so much gear that he looks like he is going on an expedition- Guilty as charged.

    Quote Originally Posted by mack_turtle View Post
    I really don't see that happening any time soon. You sound like a dirt roadie. :wink:
     

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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by dgaddis View Post
    Stems are pretty cheap. Try it, see if you like it. I don't know your mechanic, but most mechanics don't know diddly about trail (I'll be honest - I know only slightly more than diddly). That statement sounds like a generalization he heard at some point, but who knows why or when it applies (to road bikes? 26" MTBs with non suspension corrected forks?).
    this was just the random sales guy I got when I called the LBS. I don't let anyone work on my bike but myself. my mechanic skills are is fine but fitting still seems like voodoo. "cheap" stems around 35mm are a bit hard to find but not impossible. I think it's fair to say that if a rider needs a 35mm stem on an XC bike for it to fit and is not extremely short, that's weird. I just wanted to see if he was onto something with the idea of the limits of stem length having anything to do with head tube angle. he basically told me that anything under 60 mm is for a gravity oriented bike. that advice meant he talked me out of coming to his store and spending money, so he must have been pretty sure of that.

    I am over the uber-short stem thing. 50mm is damn short already. going shorter might put me back where I was a year ago, with a frame that was super short. I'll play around with the new handlebar and some stems in a rational 50-90mm range. in the end, I was willing to try what a coache's online calculator recommends, but riding experience is what will matter.
    Jonathan - Austin, TX
    A Thorn in Your Sidewall

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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by mack_turtle View Post

    • given the same handlbar width and stem length, slackening the headtube should do ___ to the handling.
    • given the same HA and bar width, shortening the stem ought to do ___ to the handling.
    • given the same stem length and HA, widening the bar should do ___ to the handling.

    Define "handling" first.

    FWIW I think that widening the bar affect balance and the lever arm length and thus the force needed to actuate the bar. The tradeoff is widening a bar has an impact on the "virtual reach" so one should correct stem length accordingly. It can improves your ability to do small and fast corrections while saving you stamina even on the grippiest tires/conditions. It improves your balance and thus comfidence but you can't really say it improves the handling per se as the bike won't react differently.
    Last edited by sk_tle; 06-11-2018 at 05:42 AM.
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    Default Re: bikes getting longer, I am not getting taller

    Quote Originally Posted by mack_turtle View Post
    one question for Kris: when you're looking at those three dimensions, is that mostly for designing a frame with custom geometry, or for making a stock bike fit a rider? is that method equally useful for both?
    If I'm designing a bike that's stock, I'm first looking at terrain to determine the geometry and picking a fork that's appropriate, along with wheel and tire sizes. For the exercise, I'd first design the bike around myself (I'm between a medium and large typically). Then look at average inseams and arm lengths of specific height ranges and weigh that against what terrain that particular bike I'm designing is meant to tackle. That starts to cut the variables into segments and then I can dilute that into sizes, and I'm using cockpit length based on my experience fitting so many different humans and that length is saddle tip to handlebar center in addition to the center of bottom bracket to the top of saddle. Once you know the averages, you can determine saddle heights for those averages and reaches for those averages. At no time am I considering wheelbase or trail. I'm only considering HT angle, BB drop and CS length.

    Stock handlebars have gotten wider because the trend to wider bars happened. Your personal handlebar width? Determine that based on shoulder width and what feels natural, so if that means cutting your bars because they feel too wide, then yes, cut them.

    Quote Originally Posted by mack_turtle View Post
    this brings up an interesting question for me: with modern XC/ trail bikes that have slightly longer reaches than years past, slacker HAs in the 68-70 degrees, and are generally being ridden with wider bars, at what point is a stem "too short" for the sake of handling on technical trails? is there any sort of useful generalizations about head tube angles and stem lengths? bar width and stem length?

    someone pointed out to me that a <50mm stem on a frame with a head tube that steep would adversely affect the handling due to the relationship between the stem and the fork trail. I have yet to wrap my head around fork trail, but a 480mm A-C rigid fork with a 45mm offset might be daft.
    My honest to goodness opinion: A Trail is where you ride your bike. Trail as in that measurement between fork offset and head tube centerline? It's a meaningless number given way too much emphasis and most likely why so many production bikes and fitting creates so many questions like these. Head tube angle, bottom bracket drop and chainstay length. Read those three in combination with one another as one complete set of data points that are not separate. They all work together to determine handling. Think about your terrain, and your riding style first. Weigh that against the bikes geometry and set up you're looking at. For an engineer or designer, Trail is something that is considered but honestly, I think it creates too much confusion amongst consumers. The geometry points I mentioned above are the ones consumers really need to be considering as they are the most directly related to how bikes handle.


    If my memory serves me correctly, we've had this type of conversation before. I think you've been fiddling with your fit/setup for some time now? Taking a wild guess, it sounds like you're in between stock sizes. This is one reason many riders actually seek out an experienced builder.
    Kristofer Henry : 44 BIKES : Made to Shred™
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    Default Re: bikes getting longer, I am not getting taller

    I just bought a bike w/ 500mm of reach and a wheelbase over 50 inches long for general usage--I encourage anyone interested to give the new school stuff a try.
    Feels a lot like skiing, which is not something I usually get from my bikes..
     

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