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Thread: XC Seat Height?

  1. #1
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    XC Seat Height?

    I see in most of the photos posted in this forum, most XC seats seam to be at a height much higher than the handlebars. I'm wondering if I am missing something in perfoamnce and / or comfort?

    Is this to maximize your leg reach for more power? Better aerodynamics? It would seem that it would put a lot of weight on your hands? Likewise, how do you get your "sit" bones to hit your saddle properly when leaning over at such an angle?

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    You are talking about two seperate things. First, seat hight should be adjusted to leave a slight bend to the knees at the bottom of your pedal stroke. This is the standard for most riders. Then, different stem lengths and angles can be used to tune to confort/handling and riding styles. Details on the second part can be found in many threads on this site.

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    Quote Originally Posted by JPark
    You are talking about two seperate things. First, seat hight should be adjusted to leave a slight bend to the knees at the bottom of your pedal stroke. This is the standard for most riders. Then, different stem lengths and angles can be used to tune to confort/handling and riding styles. Details on the second part can be found in many threads on this site.
    Yep.

    Seat height, fore/aft positioning and angle have nothing to do with handlebar height/position.

    Get your seat position figured out, so that you can actually produce power on the bike, and go from there.

    I see a lot of "XC" guys who look like they've never pedaled a bike before. Knees pointing outwards, lots of knee bend at the lowest point of the pedal stroke, etc. This is a great reason to buy or borrow a track bike; your inefficient position will be revealed very quickly.

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    Quote Originally Posted by Le Duke
    Seat height, fore/aft positioning and angle have nothing to do with handlebar height/position.
    I disagree. The relation between the two dictates how bent you need to be at the hips. So if you have a steep seat angle you can tolerate lower handlebars, and vice versa.

    There's no single "correct" saddle or handlebar location, it's all about tradeoffs.

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    Your pelvis should remain mostly vertical so the weight remains on the sit bones, that's a factor of core strength in the ab's. I think this is where some people have issues with numbness in their private parts, if they lack core strength and their pelvis tilts forward so the pelvic bone rests on the front of the seat, there's weight on the nerve. That's also where a lot of lower back pain comes from with the classic XC riding position, if there's insufficient core strength then the lower back muscles try to take up the slack.

    I see some people with their seat so high that their pelvis rocks side to side as well, that's a good indication it's too high.
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    Quote Originally Posted by rockyuphill
    Your pelvis should remain mostly vertical so the weight remains on the sit bones, that's a factor of core strength in the ab's. I think this is where some people have issues with numbness in their private parts, if they lack core strength and their pelvis tilts forward so the pelvic bone rests on the front of the seat, there's weight on the nerve. That's also where a lot of lower back pain comes from with the classic XC riding position, if there's insufficient core strength then the lower back muscles try to take up the slack.

    I see some people with their seat so high that their pelvis rocks side to side as well, that's a good indication it's too high.
    That seems rather confusing. It makes sense that I should set my seat up high enough so I have good extension on my legs...but the height of my handle bars would seem to have a direct correlation to the angle I need to set my seat, correct. Otherwise rolling forward takes my sit bones off the seat and puts me on the nose of the saddle. I know the higher I get my seat the more impact it has on numbness in my hands and crotch.

    Any good reference sites on this topic?

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    Quote Originally Posted by flargle
    I disagree. The relation between the two dictates how bent you need to be at the hips. So if you have a steep seat angle you can tolerate lower handlebars, and vice versa.

    There's no single "correct" saddle or handlebar location, it's all about tradeoffs.
    Based on the amount of money that professional teams spend on looking into this with all of their riders at the beginning of the season, I have to say that I think you're wrong. There's a reason that Saxobank had a life-size, 3-D model of Dave Zabriskie's TT position made when he was with them, and a reason that they still have it.

    Hell, my team spent several hundred dollars a rider to get us all in powerful, comfortable and efficient positions last year, and that was an amateur team.

    Everything starts from the saddle; stem, bars, etc. can all be adjusted once that is determined. And seat tube angle, in my experience, has relatively little to do with how YOU fit on the bike. There's a reason saddles have long, flat rails, and also a reason for setback seatposts.

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    As I said in my first post, to me seat height is most important and should be set first. Most XC riders set their seats level to slight foward tilt. A good ergonomic saddle(cut out or similar) should solve most of your issues in the rear area. Ergonomic grips will help for the hands. Further confort can be gained in both areas with stem lenght/angle, but, remember all changes in this area will affect handling and climbing.

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    Don't know if I can post links to other sites, but there was a good thread on slowtwitch about saddle height by Dr. Coggan: http://forum.slowtwitch.com/gforum.cgi?post=1163166
    96% of greater trochanteric height will allow you to make optimal power and still have enough bend in the knee to hover over the saddle on rough terrain.

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    Anybody moderately into racing and training that hasn't had a professional bike fit is missing out big time in a huge part of performance on the bike.

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    Quote Originally Posted by goneskiian
    Anybody moderately into racing and training that hasn't had a professional bike fit is missing out big time in a huge part of performance on the bike.
    How huge?

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    I was professionally fit on my road bike, and setup both my mtb's with the exact same saddle position: height and setback. Road bars are 3" below the saddle, mtb bars about 2" at the bar ends. I think saddle position is the most important to establish first, then adjust stem length for reach, and bar height for comfort or performance.

    Before being fit, my saddle was too low, and my left leg was putting out more power per stroke than my right. After raising the saddle, and attaining a 150º knee angle, my power was equal from side to side, and slightly higher overall.

    Saddle position is extremely important and can affect power and comfort greatly.
    "Confidence is the feeling you have before you fully understand the situation".

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    If saddle height were so crucial, it would follow that crank length would also be crucial, yet most "pro" bike fitters seem content with the 2 (maybe 3) sizes available.

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    Saddle position is the most importent component of correct bike fit. Without correct position you give up huge power , and risk injury to knees and back . Bar height ,stem length etc. are all secondary to saddle position . If you are not able to determine the correct position on your own it is well worth the investment of seeking out proffesional help.

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    Crank length isn't as critical on a MTB compared to a road bike, you'd normally spend a good bit of a MTB race out of the saddle climbing, sprinting, descending etc. unlike a road bike where all those 2.5mm increments might make more of a difference.
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    Quote Originally Posted by rockyuphill
    Crank length isn't as critical on a MTB compared to a road bike, you'd normally spend a good bit of a MTB race out of the saddle climbing, sprinting, descending etc. unlike a road bike where all those 2.5mm increments might make more of a difference.
    Which is equivalent to saying that saddle height isn't as crucial.

    Which I kind of agree with, in the sense that on a road bike you spend more time in specific positions than on the mountain bike, and bike handling issues are less important.

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    Quote Originally Posted by rockyuphill
    Crank length isn't as critical on a MTB compared to a road bike, you'd normally spend a good bit of a MTB race out of the saddle climbing, sprinting, descending etc. unlike a road bike where all those 2.5mm increments might make more of a difference.
    Yes, but 90% or more of my time every week is spent training for races.

    As such, that means lots of long, seated efforts on the way out to my local trails, or seated efforts while riding up fire roads or trails that are most efficiently climbed while on the saddle, building aerobic power.

    And, let's be honest, there are plenty of people with positions that are off not by 2.5mm, but by 25mm or more, who would most definitely benefit from a professional bike fit. The vast majority of MTBs I see look like they were cobbled together with no thought given to the actual act of riding them; most are a combination of parts thought to suit a certain application (weight, strength, budget), that are slapped on a frame and tightened down without a second thought.

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    Quote Originally Posted by flargle
    If saddle height were so crucial, it would follow that crank length would also be crucial, yet most "pro" bike fitters seem content with the 2 (maybe 3) sizes available.
    Generally speaking, most bikes come stock with cranks that are appropriate for a person buying that size of frame, for that application.

    Example: On my road bike, I ride 170mm cranks. Why? I'm 5'6", with legs of very slightly more than normal length. If I switch from my road bike to my track bike, I raise my saddle by 5mm. This is great, because it helps/forces me to spin a higher cadence, smoothly, while clearing the banking on a steep track. And, as a result, I have the same leg extension, and no problems switching between them.

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    How do you know that 170 is optimal? Have you tested 165 or 175?

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    Catharine just finished getting fit by the probably the best in the business (Andy Pruitt).

    No big change was made to her bike, the seat height was in the correct range, the bar height was good, the fore-aft was good. That part of the bike fit was good.

    His recommendation were for things that are much harder too change. The big three were
    1. Lower Q-factor.
    2. Wider seat so she sits on her sit-bones.
    3. A bar with more sweep (she already runs a 9 degree sweep bar)

    The interesting thing is he didn't have any fancy technology. He did it the old fasion way.

    If you are getting a fit and some body is charging you a couple of hundered dollars to use their laser fitting system, you are probably spending more than you need too.

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    Quote Originally Posted by LMN
    The big three were
    1. Lower Q-factor.
    2. Wider seat so she sits on her sit-bones.
    3. A bar with more sweep (she already runs a 9 degree sweep bar)
    What kind of pedals is she running?

    Who is her saddle sponsor?

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    Quote Originally Posted by Le Duke
    And, let's be honest, there are plenty of people with positions that are off not by 2.5mm, but by 25mm or more, who would most definitely benefit from a professional bike fit. The vast majority of MTBs I see look like they were cobbled together with no thought given to the actual act of riding them; most are a combination of parts thought to suit a certain application (weight, strength, budget), that are slapped on a frame and tightened down without a second thought.
    Are you looking at racers or recreational riders? If you are looking at racers are you looking at Cat 2s and 3s or Cat 1s?

    I think you are basing your opinion here on experience you don't have. You are relatively new to MTB racing. Are you telling me that after a single year of MTB racing you are qualified to critique the fit? MTBing and road racing are different sports.

    The experienced MTB racer has developed a fit for what they think is important to their riding (climbing, descending, cornering, ect...) MTB set-up is all about comprimise, what you comprimise depends on where you ride and your skill set.

    What I think it neat is how every region has a different fit style. The bike set-up that is optimal in Ontario, is not optimal in BC and vice versa.

    Honestly proffesional fitter scare me. I am constantly horrified by the MTB set-up that comes out of professional fitters. Most fitters are roadies who do not understand the demands of MTB racing and the compromises that have to be made.

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    Quote Originally Posted by Le Duke
    What kind of pedals is she running?

    Who is her saddle sponsor?

    Shimano and Selle Italia

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    Quote Originally Posted by LMN
    Catharine just finished getting fit by the probably the best in the business (Andy Pruitt).

    No big change was made to her bike, the seat height was in the correct range, the bar height was good, the fore-aft was good. That part of the bike fit was good.

    His recommendation were for things that are much harder too change. The big three were
    1. Lower Q-factor.
    2. Wider seat so she sits on her sit-bones.
    3. A bar with more sweep (she already runs a 9 degree sweep bar)

    The interesting thing is he didn't have any fancy technology. He did it the old fasion way.

    If you are getting a fit and some body is charging you a couple of hundered dollars to use their laser fitting system, you are probably spending more than you need too.
    That's interesting... Pruitt is one of the pioneers of the "laser fitting systems" as you put it and charges well more than a couple hundred dollars to use such a system in his clinic in Boulder. Did Catharine get her fitting done by Pruitt off-site, or did he just choose not to use all those expensive tools at his disposal?

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    Quote Originally Posted by scooter2468
    That's interesting... Pruitt is one of the pioneers of the "laser fitting systems" as you put it and charges well more than a couple hundred dollars to use such a system in his clinic in Boulder. Did Catharine get her fitting done by Pruitt off-site, or did he just choose not to use all those expensive tools at his disposal?
    I wasn't there so can't give all the details.

    My guess is he recognizes that for MTBing a "laser fitting system" isn't practical.

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    As LMN said there is a range for saddle height. There is not one set measurement for each rider and that is it. There are also a number of issues to consider before just saying you need x degree of bend in your knee and thats great.

    A person's flexibility needs to be considered. If they have really tight hamstrings or are tight in other areas it might not allow them to fit and or be efficient in certain positions. You can set them up in a position but when they leave they will have issues if it is not correct.

    Past injuries are another. Surgeries, muscle damage, anything else can lead to a person not being efficient or comfortable in a certain position.

    Type of riding. There is a difference between mtn and road it is fairly small some riders may not change saddle height at all but there can be a difference.

    A fitter should check your range of motion and run through some questions before setting you up with x degree bend in your knee.

    There is more too, but going to a good fitter can help a ton. If you spend a couple grand on your bike why not take the time and spend a couple hundred on being set up properly.

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    Quote Originally Posted by Le Duke
    Based on the amount of money that professional teams spend on looking into this with all of their riders at the beginning of the season, I have to say that I think you're wrong. There's a reason that Saxobank had a life-size, 3-D model of Dave Zabriskie's TT position made when he was with them, and a reason that they still have it.
    That sort of was my point. The tradeoff in TT fit is between power and aerodynamics, and the goal is to find the optimal middle ground. I'm pretty sure Z's seat angle is steeper on his TT than on his road bike, and if he rides a mountain bike, slacker and probably a hair lower, and if he raced downhill, slacker and lower still.

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    Here's a question: Is the most efficient position also the most comfortable or is there some compromise there? I've always setup my own bikes for comfort/handling first. The saddle position, relative to cranks, I decided by which felt the most efficient on hill climbs (i.e. the position that felt most powerful). I have had one professional fit on a road-bike, but I don't like it! It doesn't feel as comfortable as I feel I could have done myself. I wonder though if the professional got it right (this bike is only used for racing) and maybe if I adjust it now I'll lose efficiency in some way.

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    Quote Originally Posted by LMN
    I wasn't there so can't give all the details.

    My guess is he recognizes that for MTBing a "laser fitting system" isn't practical.
    Why wouldn't it be? They just set the bike in a trainer, put a bunch of dots on critical points, and let you pedal for a bit.

    Yeah, I know, folks stand up, slide around on the saddle, whatever, on mountain bikes, but folks stand up on road bikes, time trial bikes, track bikes, etc... and they use the lasers for the fit sessions on all those bikes. One common thread for riding any type of bike is that there is one optimal point for saddle position (for that person on that bike), and the laser systems help them find that point by discovering deficiencies that may not be visible to the naked eye. Heck, some of the typical deficiencies they find w/ those systems are problems w/ the rider's shoes, to include cleat placement and whether inserts are needed to correct an alignment problem. There's nothing unique about mountainbiking that would make the sophisticated systems unsuitable.

    I don't know why Andy didn't use the laser system in this instance, but I doubt it has anything to do w/ the fact that it was a fit session for a mountainbike. Probably more to do w/ the fittee not wanting to pay for it, but that's just speculation on my part.

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    Quote Originally Posted by scooter2468
    One common thread for riding any type of bike is that there is one optimal point for saddle position (for that person on that bike)
    Optimal in what sense?

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    Quote Originally Posted by LMN
    The experienced MTB racer has developed a fit for what they think is important to their riding (climbing, descending, cornering, ect...) MTB set-up is all about comprimise, what you comprimise depends on where you ride and your skill set.
    So true!

    It takes time, lots of time to find optimum. I start at saddle hieght, and than adjust Fore/Aft based on feel. A bit back helps with the low torque "grunt" efforts. A bit forward helps with my spin. And this must be dialed in AFTER the suspension is tuned.. sag, (front or rear) will effect where you are relative to the spindle.

    From there, handle bar drop/reach. I like a bit stretched out and low position. I am 5'10", ride a 23.6" TT with a 72.2 ST angle and use a 120mm stem with no spacers and a 580mm flat bar with 4deg bend. Hardtail with 80mm fork.

    This is where I find my best balance, power, ability to carve the corners, and a good "arm feel" when standing.

    Some riders would find my bar position way to low and long, and spooky on descents. But its where I have settled for my optimum... at this time

    I did do a laser fit and the fitter ( http://www.blackdiamondtherapy.com/) suggested I raise my saddle slightly and put a spacer on my left pedal (to increase Q). It worked, my left knee would swing a bit, and the tiny spacer corrected it and I could actually feel the improvement.. my left leg now feels more square over the pedal when driving the down stroke.

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    Quote Originally Posted by LMN
    Are you looking at racers or recreational riders? If you are looking at racers are you looking at Cat 2s and 3s or Cat 1s?

    I think you are basing your opinion here on experience you don't have. You are relatively new to MTB racing. Are you telling me that after a single year of MTB racing you are qualified to critique the fit? MTBing and road racing are different sports.
    Even some Cat1s I've raced against have some issues. Knees not tracking correctly, saddles VERY low, crazy short stems (DH-like), etc.

    I'm not trying to say that I can look at someone as they're riding by and say "Raise your saddle exactly 1.8mm!"; but just making a general statement about what I've observed. There are some terrible bike fits out there, and I don't have to be Andy Pruitt to point them out. Unless MTB racing and road racing are even more different than I thought, I don't think improperly tracking knees are ever a good thing.

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    One article I read suggested that you set your seat height, based on your leg length & comfort, then set your handlebar height so that you stay balanced when you remove your hands from the bars. Once you have that position, now you adjust your bar height based on your style of riding, flexibility, etc. A more recreational rider keeping the bar high and dropping the bar for racers / more flexible folks.

    I'm sure if I take my hands off the bar I be very "weight forward" and off balance, but not nearly as weight forward as some of these bikes I see with the seat 6 inches higher than the handle bars.

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    Quote Originally Posted by Henchman
    Here's a question: Is the most efficient position also the most comfortable or is there some compromise there? I've always setup my own bikes for comfort/handling first. The saddle position, relative to cranks, I decided by which felt the most efficient on hill climbs (i.e. the position that felt most powerful). I have had one professional fit on a road-bike, but I don't like it! It doesn't feel as comfortable as I feel I could have done myself. I wonder though if the professional got it right (this bike is only used for racing) and maybe if I adjust it now I'll lose efficiency in some way.
    Most of the time when you get a fit there is going to be an adjustment period. Especially if any extreme adjustments have been made. Comfort plays a huge role in efficiency. Someone can put you in what they believe is a great position but if you are constantly adjusting and moving to get comfortable then any power you might have gained is lost. Depending on what type of riding you are looking to do there could be some compromises but comfort really is a key element.

    If for any reason you did have any major adjustments done during your fit it is also a good idea to baby step your way into that position if it doesn't feel right at first. I would not change something and then go out and hammer the hell out of it on the Tuesday night ride or weekend race without seeing how it felt before hand.

    Also, make sure you let your fitter know what you are feeling. If you leave and something does not feel right go back and tell them, otherwise they cannot work with you to fix the issue. You paid for it so if you are not satisfied or have any doubts let them know and they should within reason be more than willing to take care of you.

    Not sure if I understood correctly but do you only ride the position the fitter did in races? If so, you really need to race what ever position you train in.

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    Set the saddle height first, comfortable proper leg extentsion and for and back position...

    If you ride mountains decide if you are going with one height (compromise) or going with two heights one for up and one for down.

    Then set the bars up, ones flexibility may limit how low you go.

    Again if you ride mountains with big steep downs, that will probably set the highest position.

    Then maybe nearer the low end for fast flat and rolling riding, or maybe a little higher for lots of steep down hill..

    Not suggesting you change the set up for every ride...but for sure the set up will change if your riding the Trans Rockies, and then doing a 2 hour XC burn...

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    Quote Originally Posted by rockyuphill
    Your pelvis should remain mostly vertical so the weight remains on the sit bones, that's a factor of core strength in the ab's. I think this is where some people have issues with numbness in their private parts, if they lack core strength and their pelvis tilts forward so the pelvic bone rests on the front of the seat, there's weight on the nerve. That's also where a lot of lower back pain comes from with the classic XC riding position, if there's insufficient core strength then the lower back muscles try to take up the slack.

    I see some people with their seat so high that their pelvis rocks side to side as well, that's a good indication it's too high.
    THANKS!

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    Quote Originally Posted by scooter2468
    Why wouldn't it be? They just set the bike in a trainer, put a bunch of dots on critical points, and let you pedal for a bit.

    Yeah, I know, folks stand up, slide around on the saddle, whatever, on mountain bikes, but folks stand up on road bikes, time trial bikes, track bikes, etc... and they use the lasers for the fit sessions on all those bikes. One common thread for riding any type of bike is that there is one optimal point for saddle position (for that person on that bike), and the laser systems help them find that point by discovering deficiencies that may not be visible to the naked eye. Heck, some of the typical deficiencies they find w/ those systems are problems w/ the rider's shoes, to include cleat placement and whether inserts are needed to correct an alignment problem. There's nothing unique about mountainbiking that would make the sophisticated systems unsuitable.
    Mountain biking is incredibly dynamic.

    Putting a person on a trainer and setting them up is optimizing their position for riding on flat smooth ground, probably at a high cadence. Completely different then what you actually ride on.

    The varience on where you sit and how you put out power is fairly significant.

    I admit though, I am biased. I have seen too many people spend a lot of money and end up with a really crappy fit from somebody who has lasers. There seems to be this belief that all you need to do to charge $500 for a fit is buy some fancy equipment and take a weekend course.

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    LMN, I understand the narrower Q-factor and wider saddle but what was the reason for more sweep? 9 degrees is already pretty agressive. Since she was already pretty dialed in on her fit, how did she get to that position? Any tips or hints you can give? Thanks.

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    Quote Originally Posted by LMN
    Mountain biking is incredibly dynamic.

    Putting a person on a trainer and setting them up is optimizing their position for riding on flat smooth ground, probably at a high cadence. Completely different then what you actually ride on.

    The varience on where you sit and how you put out power is fairly significant.

    I admit though, I am biased. I have seen too many people spend a lot of money and end up with a really crappy fit from somebody who has lasers. There seems to be this belief that all you need to do to charge $500 for a fit is buy some fancy equipment and take a weekend course.
    First, let me say I have no argument with you last paragraph. But, you've got a bit of faulty logic in your opening paragraphs. If there's too much variation in how one sits on and subsequently rides/pedals a mountain bike to justify a thorough fitting to determine the optimal position, then there's no point in doing anything to even get near the optimal position. Why bother, right?? You're always moving around anyway.

    We both know that's absurd, though. Of course there's an optimal seat position that allows for the most efficient riding in most conditions, whether it's attained by some guy watching you ride along and then recommending changes (the old school way) or by setting things up for a precise computerized/laser-ized fitting, or somewhere in between.

    I'd be willing to bet that if you asked, you'd find that whether Dr. Pruitt used the lasers he has access to, or whether he just took a few measurements with a tape measure and goinometer, he had the bike on a trainer and the rider pedaling on the trainer while he observed. No reason whatsoever that he couldn't have used the computerized system to augment his observations.

  40. #40
    LMN
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    Quote Originally Posted by System
    LMN, I understand the narrower Q-factor and wider saddle but what was the reason for more sweep? 9 degrees is already pretty agressive. Since she was already pretty dialed in on her fit, how did she get to that position? Any tips or hints you can give? Thanks.
    Increasing the sweep would bring the shoulder, elbows and hands in line which should allow better power transfer. You get a similar effect by using bar-ends.

    Catharine's position has evolved over the years. She has tried all kind of different set-ups and in the end settle on the one that she felt was the most comfortable and allowed the best power transfer.

  41. #41
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    Quote Originally Posted by flargle
    Optimal in what sense?
    Efficiency, typically.

    Don't be argumentative, you know full well that for any given person on any given bike, there's an optimal position for the saddle. If not, why not just put it anywhere?

  42. #42
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    Quote Originally Posted by scooter2468
    Don't be argumentative, you know full well that for any given person on any given bike, there's an optimal position for the saddle. If not, why not just put it anywhere?
    If so, why do telescoping seatposts exist? Why do time trial bikes have steeper seat angles than road bikes? It's a pretty simple point, there is not a single optimal position for the saddle, it's context-dependent.

  43. #43
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    Quote Originally Posted by scooter2468
    any given person on any given bike, there's an optimal position for the saddle. If not, why not just put it anywhere?
    Couldn't agree with you more.

    But that optimal position is going to depend on many factors (size, bike, terrain, riding style, flexibility, ....) More factors (IMHO) than an algorithm can account for.

    The way I look at it is doing a good laser fit is going to put you in the ball park. The fine tuning is going to come through communication between the rider and fitter and small adjustments over time. If the fitter is good enough to make those adjustments, then they are good enough to get you in the ball park the old fashion way.

  44. #44
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    Quote Originally Posted by flargle
    If so, why do telescoping seatposts exist? Why do time trial bikes have steeper seat angles than road bikes? It's a pretty simple point, there is not a single optimal position for the saddle, it's context-dependent.
    I guess you missed the crucial point about an optimal position for a given rider on a particular bike. Therefore, it is expected that someone's road position will be different than a TT position. Like you said, context-dependent. But, the seated position on your mtb is one context and there's an optimal position for it. Yeah, I know... telescopic seatposts exist, and they do because the context will change, but you set the saddle in the 'optimal' position for general riding, then accept that you can lower it to get it out of the way for a completely different context, one where the most efficient, powerful pedalling isn't the crucial factor in where you'd want your saddle.

  45. #45
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    Quote Originally Posted by Photo Kid
    One article I read suggested that you set your seat height, based on your leg length & comfort, then set your handlebar height so that you stay balanced when you remove your hands from the bars. Once you have that position, now you adjust your bar height based on your style of riding, flexibility, etc. A more recreational rider keeping the bar high and dropping the bar for racers / more flexible folks.
    I guess you could spend all sorts of $ and time getting fit for the bike and never actually have time to ride. Get an efficient stroke set and tune your bars to your level of aggressiveness. I prefer less break @ my knees, but still enough that I'm fully engaging my quads on the push. My bars a fairly low, but could be 1cm lower.

    I can very comfortably pedal in circles and apply pressure @ any point. I can pop up/out of the saddle on hard surface climbs like a roadie and move out. I can ride as far/long as I care to, but I challenge myself @ every point so there comes a time that my output chews thru my caloric intake and therefore I hang it up.

    As an goon that rides for personal challenge only, I'll get/set the fit that suits me using my own set of preferences and leave it at that. You can take 3 years of testing incremental changes of .01mm or you get set knowing there will be give/take and deal w/ the rest.

    Here's an elevation view of my bike:



    Although, being fit by a pro not only allows you to blow $, it provides a means whereby you can blame someone else on your weak riding, so that may be an option worthy of your (the general public) consideration.

    Now go ride.

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    Quote Originally Posted by selector
    I guess you could spend all sorts of $ and time getting fit for the bike and never actually have time to ride.


    As an goon that rides for personal challenge only, I'll get/set the fit that suits me using my own set of preferences and leave it at that. You can take 3 years of testing incremental changes of .01mm or you get set knowing there will be give/take and deal w/ the rest.


    Although, being fit by a pro not only allows you to blow $, it provides a means whereby you can blame someone else on your weak riding, so that may be an option worthy of your (the general public) consideration.

    Now go ride.
    Clearly written by someone who's never had a bike fitting done and had it plainly shown how wrong we can sometimes be when setting our bikes up ourselves.

    BTW, when you get fitted, it doesn't take forever. You still have time to ride your bike later, and maybe even more than before if the fitting helps correct or prevent injury.

  47. #47
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    Quote Originally Posted by scooter2468
    Clearly written by someone who's never had a bike fitting done and had it plainly shown how wrong we can sometimes be when setting our bikes up ourselves.
    Why restate the obvious????

    How wrong????? What the ph***k do you know about how/where I ride and what suits me??? Nothing. How are you able to determine my current level of comfort and efficiency??? Puhleeze dude... you don't know me from the man in the moon. Please don't suppose your philosophical preferences are for everyone. Take a bike, any bike... it's comprised of components and nothing more. A fitting invovles at least (2) people; rider and fitter. At the end of the day, it's the rider that needs to be comfortable and hopefully have optimum positioning. If you're suggesting a solo rider can't make it thru the testing process for themselves and get damn close, you're nothing other than strictly wrong. In the end it's a bike being ridden by a person, not a fitter. The fitter can use math and gizmos until they're blue in the face, but in the end, the rider is the one on the hook to get it done.

    Just like all the whining and crying in MX re: suspension... I've heard it adnauseam... sort yer chit and shut up. Anything else is an excuse.

    If you elect to try to get to the knife's edge thru means of professional fitting, that's your choice. If you think the knife's edge will mitigate or counter your bad nutrition habits (for instance), you're wrong. If you need the knife's edge to win, you are, by definition an elite rider/athlete and such measures should be provided to you at no expense and as part of the training regimen.

  48. #48
    LMN
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    Quote Originally Posted by selector
    Why restate the obvious????

    How wrong????? What the ph***k do you know about how/where I ride and what suits me??? Nothing. How are you able to determine my current level of comfort and efficiency??? Puhleeze dude... you don't know me from the man in the moon. Please don't suppose your philosophical preferences are for everyone. Take a bike, any bike... it's comprised of components and nothing more. A fitting invovles at least (2) people; rider and fitter. At the end of the day, it's the rider that needs to be comfortable and hopefully have optimum positioning. If you're suggesting a solo rider can't make it thru the testing process for themselves and get damn close, you're nothing other than strictly wrong. In the end it's a bike being ridden by a person, not a fitter. The fitter can use math and gizmos until they're blue in the face, but in the end, the rider is the one on the hook to get it done.
    You don't need much experience to see from a glace a couple of things on your bike that are outside the norm. Maybe they peculiarities related to your body, or, more likely, they are thing you haven't tried.

    If you were to bring your bike to me to fit. Even before I saw you on it there would be three things I would want you to try
    1) You seat is at a, "I want to use Viagra for the rest of my life", angle. Your saddle that far nose up can put pressure where you don't want pressure. It also makes it harder to get your weight forward on steep climbs.

    2) The brake levers are very high up. At that angle you may have twist your wrists to operate them which means a weaker grip.

    3) From the side it looks like you have your bars sweeping down. An upward and backward sweeps allow a stronger grip and more control.

    Those are just suggestions. You may try them out and find they don't work for you, nothing wrong with that.

  49. #49
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    Photo Kid:

    I have found http://www.competitivecyclist.com/za...LCULATOR_INTRO
    useful. It will get you in the ballpark to start. I also like to use a white colored pencil (prisma color brand) to mark seat post height, brake lever position etc. This helps when making small changes and can help set a bike bake up after a crash. I also found the seat post slowly slipped on my my hardtails. Marking it made it visible. Good luck.

  50. #50
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    Wow, this thread has gotten totally out of control.

    First, to Selector, I agree with LMN, if you were to go to a pro fitter, they would make several changes to your bike that would result in more comfort and allow you to perform better on the bike. Having said that, it's your bike and you can set it up however you want.

    Second, I do agree that people have the ability to setup their bikes themselves, with relative precision, if they know what to do and how to do it. I've been riding for almost 20 years and got my first professional fitting last year. I researched the subject for years, learning the different philosophies of bike fit, what adjustments created what responses, and what adjustments could be made to eliminate pain or discomfort in certain areas of the body. I lived in a very small town, far away from a bike shop with a fitter, so I did this our of necessity.

    A couple of things about me. My right foot pronates, which causes my right knee to dive toward the top tube during my pedal stroke. My neck has always hurt after a couple of hours of riding. Always! So I made adjustments for my pronating foot. Purchased some LeMond Wedges and experimented until my knee tracked in what looked like a straight line up and down. My left knee always seemed to track perfectly up and down. I was never able to get rid of my neck pain.

    I moved to Phoenix last year, and a local shop started doing Specialized Body Geometry 3D fits, using a video camera and some slick computer software. I paid for the fit, which was done by an ex pro cyclist, and to my surprise, he said I had nailed several of the important parts of my bike fit already, but several needed significant change.

    He checked my flexibility, range of joint motion, etc. Then he watched me pedal the bike on a trainer. He had me bring the power up to 250 watts and then video was shot. The first thing he noticed was that my power from leg to leg was off. My left leg was 53% and my right 47% of power output. He also noticed my left knee was swinging out then looping toward the top tube during my stroke. I would have sworn my left knee was tracking perfectly straight, but there it was, on the video! My saddle was also a bit low and forward, so he raised it about an inch, which I thought was way too much at the time, and back about an inch. This got me behind the pedals with better leg extension. More video was shot and power readings taken. 50% power from both legs after those changes, and my left knee was tracking straight. He also noted that the wedges I had on my right shoe were perfect and my right knee was tracking perfectly. Those were the only adjustments he made. The saddle height felt horrible for the first couple of rides, but then it started feeling better and now feels much better than before. I used to get small aches and pains in my legs, but now those are completely gone, and my neck pain is completely gone.

    I think there are a lot of things in a bike fit that you can do on your own if you know what you are doing, but there are some things that you need someone else to check for you. You can't always just go by feel. Just because it feels good doesn't necessarily mean it's right. It might feel good just because you've been doing one way for a long time and are used to it. Fitters will see things you can't see, and have the knowledge of what adjustments create what changes in comfort and power. The optimum position for me might not be the optimum position for you, but a good fitter will be able to help you find your optimal position.
    "Confidence is the feeling you have before you fully understand the situation".

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