Would an 1/8" really make a difference.
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Would an 1/8" really make a difference.
I have an issue with my left knee that I have been trying to work around. I have, for a time, had my saddle too high and have gone through the three or four different measurement theories as to a good starting point and it was very helpful. I have/had my doubts as to the real-time difference a 1/8" - 3/16" height change would make in my cockpit feel but it seems to have made a felt difference. Am I just hoping for an improvement or would that small amount really be something I would feel as an improvement? Should I be looking for another adjustment or just ride it and see where I go with it? Any information as to what else I can do or look into to help would be very appreciated. I know that I could/should have a fitting but to be honest, I do not know of anyone ever remotely close to me that I feel I could trust so I am on my own. I also realize that there have been dozens of posts on the subject and about the same in videos but most veer off to involve so many variables that, for a old man trying to just feel good on his bike, it is far too complicated. Need to know that I have a good starting point and then what is the next thing I should be looking for. If this is truly beyond me and the consensus is that the only way forward is a professional fit please just say so. Otherwise I just need to know what my next step should be or do I just ride the bike and enjoy the last adjustment?
Be safe, Frank.
Be safe, Frank.
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I've had knee problems in the past and my knees feel better with fuller extension. I have noticed that at the extreme high end of adjustment, (which is where I like to ride) small distances matter a lot. When I switch seasons (shoe sole thickness--Chucks vs hiking boots, for instance) I'll fasten my back reflector almost at the seat post locking collar (like 1/4" or a bit farther away) so that I can make quick small adjustments with that distance as a reference for easy visual measurement and by the time I've gone a block or two I'll have it dialed in. I think as you do more of it you will learn what you like and it will be easier to get it right quickly.
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It seems to me that if a saddle is set on the verge of being too high, then a small incease in heigth, even as little as 1/8" may well cause a problem in an already troublesome knee. Carbonfiber Boy has posted numerous times an accepted method, one I use myself successfully. Sit normally in your saddle and place the heel of the shoe on the peddle with the leg straight but not locked out. This illiminates considerations of cleats, and sole thickness. From there, you can go up or down a mm or two based on riding experience. I have a troublesome right knee myself and my solution is to strengthen the muscles and ligaments that surround the knee with knee specific exercises. Almost all of our movement is forward with almost not to the sides.
The link shows some knee exercises. https://www.webmd.com/pain-managemen...ysical-therapy For myself, I focus on exercises that emphasize lateral moves such as a tennis player shuffling from left to right or a basketball defensive player shuffling sideways while guarding someone on offense. I do these at least once a week or more during flarer-ups. I'm 81 y.o. and so far my knees are doing well. If I don't do the exercises discomfort persists.
The link shows some knee exercises. https://www.webmd.com/pain-managemen...ysical-therapy For myself, I focus on exercises that emphasize lateral moves such as a tennis player shuffling from left to right or a basketball defensive player shuffling sideways while guarding someone on offense. I do these at least once a week or more during flarer-ups. I'm 81 y.o. and so far my knees are doing well. If I don't do the exercises discomfort persists.
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1/8” is absolutely a significant change. Especially if you are riding long distances or otherwise pushing your limits, including experiencing knee pain.
My suggestion is to ignore all the formulas once you get your saddle into the correct ballpark. Go for a ride with your allen keys handy and play with minor adjustments of saddle height as you ride. You should probably mark the starting point so you can get it back if you make an adjustment that doesn’t work out.
Something else to consider is that saddle height isn’t the only thing that can cause knee pain.
My suggestion is to ignore all the formulas once you get your saddle into the correct ballpark. Go for a ride with your allen keys handy and play with minor adjustments of saddle height as you ride. You should probably mark the starting point so you can get it back if you make an adjustment that doesn’t work out.
Something else to consider is that saddle height isn’t the only thing that can cause knee pain.
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You could start with my bike fitting primer, here: https://www.bikeforums.net/21296948-post3.html
And yes, small differences in saddle height do make a difference, fore-and-aft dimensions not so much. There you'll feel a difference of a centimeter or two.
And yes, small differences in saddle height do make a difference, fore-and-aft dimensions not so much. There you'll feel a difference of a centimeter or two.
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Thanks all. I feel like the front to back, over the BB, is good but the height is my downfall. It is especially difficult to transpose the "correct" fit from my hybrid to my gravel bike in spite of the fact the rear triangles are identical. Will continue to adjust and I have used a similar technique with the seat post with masking tape with making a reference line for seat post height.
Be safe all, Frank.
Be safe all, Frank.
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Get your saddle height in the ballpark first before worry too much about other stuff. Wrong saddle height can be knee pain but a bunch of other stuff also can be knee pain too.
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
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Get your saddle height in the ballpark first before worry too much about other stuff. Wrong saddle height can be knee pain but a bunch of other stuff also can be knee pain too.
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
Thanks again all for your input.
Be safe, Frank.
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For me, a 5mm difference in saddle height or fore/aft can literally cut my speed in half -- or double it -- going up a 12% grade. (But everyone is different, so my body may just be "hyper-sensitive" to position changes.)
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The older I get, the more sensitive I become to position changes. I will absolutely feel 1 or 2 mm differences.
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The way to get the same effective seat height on different bikes with different seats is to adjust to the same knee bend. Sounds hard to do but it isn't. First, get the bike with the seat height you like. Bring it indoors and lean it next to a wall. Put on shoes with low heels, like typical cycling shoes. Get on the bike and sit in your usual riding position using the wall for support but having yourself and bike as upright as possible. Rotate the wall side pedal down. Now, put your heel on the spindle of the upside down pedal. Do not rotate your hips to reach the pedal! If you cannot reach, find a pair of shoes with enough heel that your heel reaches. Now, can you also bend your knee a touch without lifting your heel off? Does your heel lift off? Get another pair of shoes with again touch more heel or if it is really close, put a cardboard "lift" inside the shoe under your heel. There is a magic amount of heel that will allow both contact with a straight leg and contact with a slightly bent knee. (Remember, this whole time you are keeping your hips level. If you cannot straighten your leg, go to a shoe with a smaller heel/thinner sole or even go barefoot.)
Yes, it took a little work to establish your "baseline". But now, you can put that shoe on and quickly dial in any bike. Get that other bike. Adjust the seat height to that magic place. Done. (Now, different types of pedals make this a little more complicated as your foot height may change. Might take measuring your shoe on the pedal and compensating the seat height accordingly. Or having an outside observer measure down from a mark you make on the ball of your ankle to the centerline of the pedal spindle.)
Knee issues - as well as seat height, tight hamstrings can cause them as can improper foot position on the pedals and not keeping them warm enough. I've been dealing with knee issues for 40 years. I ride with a lowish seat (I do the test above in my socks, no shoe) but I have to stretch, I have to have my cleats set right and I have to keep my knees warm. I was told by an orthopedic surgeon when the symptoms showed up that not doing those things meant investing in third party replacements. Since then I have ridden 150,000 miles and still have my originals.
Yes, it took a little work to establish your "baseline". But now, you can put that shoe on and quickly dial in any bike. Get that other bike. Adjust the seat height to that magic place. Done. (Now, different types of pedals make this a little more complicated as your foot height may change. Might take measuring your shoe on the pedal and compensating the seat height accordingly. Or having an outside observer measure down from a mark you make on the ball of your ankle to the centerline of the pedal spindle.)
Knee issues - as well as seat height, tight hamstrings can cause them as can improper foot position on the pedals and not keeping them warm enough. I've been dealing with knee issues for 40 years. I ride with a lowish seat (I do the test above in my socks, no shoe) but I have to stretch, I have to have my cleats set right and I have to keep my knees warm. I was told by an orthopedic surgeon when the symptoms showed up that not doing those things meant investing in third party replacements. Since then I have ridden 150,000 miles and still have my originals.
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Get your saddle height in the ballpark first before worry too much about other stuff. Wrong saddle height can be knee pain but a bunch of other stuff also can be knee pain too.
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
Are you pushing too high a gear? Is the crank a different length than the other bike? If you set saddle height based on the other bike, then did you more correctly measure to the pedal at the bottom of it's stroke or wrongly from the BB?
Keep in mind that the "right position" might not feel perfect at first, so give it chance by riding a few miles before making adjustments. And when you do make adjustments, keep them to relatively small movements. Also keep in mind that when you move the saddle more forward on the rails or further back on the rails you are also impacting saddle height. A saddle moved further back on the rails will also make the saddle feel like it has been raised because your feet are moved further away from the pedals. A saddle moved further forward on the rails will make it feel like the saddle has been lowered because your feet are moved closer to the pedals. So keep in mind that when making fore/aft adjustment you will likely need to adjust saddle height. If your seatpost has setback be mindful of that as well because setback is another variable in the overall equation.
Iride01 is also correct that gearing and crank length can also cause knee pain. Higher cadence in an easier gear can sometimes relieve knee pain if you are regularly grinding away in a hard gear. And cranks that are too long (which I beleve is an issue that most people have, whether they experience pain or not) can absolutely cause knee pain/discomfort. The pain usually happens at the top of the pedal stroke because the long crank creates a knee angle that is too sharp. And if the knee angle is too sharp at the top of the pedal stroke it can also cause hip impingement issues. Shorter cranks can be a great solution to this problem.
So, long-story short... when you really dig into seat height it's complicated! But in order to keep it manageable without getting lost in the weeds I'd start with getting the saddle height correct using the "heel on pedal" method. From there you can make small adjustments via trial and error and you'll most likely achieve a noticeable improvement.
Last edited by Cyclist0100; 12-13-20 at 06:31 AM.
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Thanks all. I feel like the front to back, over the BB, is good but the height is my downfall. It is especially difficult to transpose the "correct" fit from my hybrid to my gravel bike in spite of the fact the rear triangles are identical. Will continue to adjust and I have used a similar technique with the seat post with masking tape with making a reference line for seat post height.
Be safe all, Frank.
Be safe all, Frank.
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I definitely feel small changes, I'm really sensitive to the change but you can get used to it quickly.
I wouldn't heavily rely on online formulas. Use them as starting points and go from there. When I get a new bike or am making adjustments I go out for a ride just to see what works. I keep actual 4mm and 5mm keys in my pocket so I can easily adjust after a bit and see how things feel. When Im happy I ride home
I wouldn't heavily rely on online formulas. Use them as starting points and go from there. When I get a new bike or am making adjustments I go out for a ride just to see what works. I keep actual 4mm and 5mm keys in my pocket so I can easily adjust after a bit and see how things feel. When Im happy I ride home
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I agree and I did make the adjustment. What I was trying to say is that I made this change and it seemed to me, to have made a big difference. I was/am asking if this could really be enough to make the difference I was feeling and wanted or was it just in my head. I apologize for the vague wording but the consensus is that it is and it is not all in my head.
Thanks for you post, Frank.
Thanks for you post, Frank.
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I would like to add this comment. I, like so many on this forum and other sites, have tried so many different saddles in search of the "correct" fit. I was on the verge of selling or converting my gravel bike when a sales person at my bike shop asked if I had ever had a real sit bones measurement? I had not, I only had my own at home measurement so he had me sit on his instore equipment. Turns out I have wide sit bones and the saddles I had been trying were way off. Once I got that straight I tried two more with the correct width and I found my present and current "perfect" saddle until I become more or less fit but at least I know what the starting point is. What all of this rambling is for is to say what a huge improvement the correct saddle made in my riding enjoyment. The 1/8" post is now I am getting greedy and want to get that fit that I only read about here.
Be safe all, Frank.
Be safe all, Frank.
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I agree and I did make the adjustment. What I was trying to say is that I made this change and it seemed to me, to have made a big difference. I was/am asking if this could really be enough to make the difference I was feeling and wanted or was it just in my head. I apologize for the vague wording but the consensus is that it is and it is not all in my head.
Thanks for you post, Frank.
Thanks for you post, Frank.
If you try the heel test fitment technique, I would suggest you have the crank in line with the seat tube, and not at the absolute bottom of the pedal stroke, where the crank arm is perpendicular to the ground. In line with the seat tube is actually where your leg is at maximum extension.
For some good info on seat height, and how much damage can be done to your body, along with how to get your seat where it should be for you, look here: https://www.stevehoggbikefitting.com...ard-can-it-be/
https://www.stevehoggbikefitting.com...d-can-it-be-2/
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Heldenberg already has knee pain, so I would advise not to make big changes in the wrong direction. So the first change should be rather small to limit the impact in case it is in the wrong direction. Often (at least in some books, like Zinn, Arnie Baker, and Priuitt) it is recommended to raise the saddle if the pain is in front or on the side, but I don't if that is a hard general rule. Caution in changing ride position was a key point made in "Road Racing, Techniques and Training" by Bernard Hinault and Claude Genzling. Claude migrated Bernhard to a different frame size, at the rate of about 1 mm per week. Of course then-Champion Hinault had legs worth a huge number of francs, but mine are quite valuable to me. It also tends to validate the idea that 1 mm changes are significant under some conditions.
But I'm not a doctor of any sort, just a cautious guy where it comes to my knees.
But I'm not a doctor of any sort, just a cautious guy where it comes to my knees.
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All good questions and I can only answer that I tried to measure consistently between the two bikes. The seats are different and I am trying to use the BB center as my point zero then run the ruler to match the angle of the seat post to set seat height. My crank arms are the same length so that is a constant. As far as pushing too high a gear I make my selection as to the load I feel in my bad knee without spinning out. I have been making a concerted effort be conscious of my rpm and knee/leg over the pedal and not splayed out. I also have to take into account the 47 years of wear and tear on my legs as a plumber so there is a definite base line I need to recognize.
Thanks again all for your input.
Be safe, Frank.
Thanks again all for your input.
Be safe, Frank.
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Frank, using BB center between two bikes is only valid if the crank arms are the same length. If not or you are in doubt, do more measurements to check how the arms compare or just change to measuring saddle to the pedal center. Should be obvious but also it should be said, we also need left to right matching as well as bike to bike matching. -- Ken
Frank.
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Heldenberg already has knee pain, so I would advise not to make big changes in the wrong direction. So the first change should be rather small to limit the impact in case it is in the wrong direction. Often (at least in some books, like Zinn, Arnie Baker, and Priuitt) it is recommended to raise the saddle if the pain is in front or on the side, but I don't if that is a hard general rule. Caution in changing ride position was a key point made in "Road Racing, Techniques and Training" by Bernard Hinault and Claude Genzling. Claude migrated Bernhard to a different frame size, at the rate of about 1 mm per week. Of course then-Champion Hinault had legs worth a huge number of francs, but mine are quite valuable to me. It also tends to validate the idea that 1 mm changes are significant under some conditions.
But I'm not a doctor of any sort, just a cautious guy where it comes to my knees.
But I'm not a doctor of any sort, just a cautious guy where it comes to my knees.
Dropper posts encourage large changes all the time. Have not heard that owners of dropper posts are being injured. More like they learn the dropped position works pretty good.
Going back to vintage operation of vintage bicycles it used to be quite common for racers to grab a spare bike, any bike, rather than wait for a wheel change. This of course worked better when everyone without exception was using Campy 1037 pedals. What happened when racers grabbed a bike way too small was they adjusted in a mile or two and continued on as if nothing had happened. When they grabbed a bike that was even very slightly too big it was hopeless. No power and no possibility of a fast corner.
Using the Hinault regimen of 1mm a week it will never be possible to correct large errors. Most errors are large. The way to find out if an error is in progress is to try stuff. Mix it up, move it around. Bike position is not about micrometric precision. It’s cold outside, we all just got a lot less flexible than we were a month ago. Stuff as basic as overall height varies between beginning of ride and end of ride. Varies with time of day and how well we slept last night.
Speaking of winter, riding lower, getting the center of gravity down, is enormously safer. No reason to care if the ride is a little slower in January. My long term experience is that once any rider puts the saddle up too high they are married to that position. Nothing, not even repetitive injuries, not repetitive surgeries, will make the saddle go down. So my new tack is put it down for winter. Might save a crash on the ice. Might allow a recovery from a slip on that one wet leaf. And after a month or two with the saddle down it might turn out that is where the saddle stays.
Last edited by 63rickert; 12-17-20 at 09:17 AM.
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Originally Posted by Road Fan View Post
Frank, using BB center between two bikes is only valid if the crank arms are the same length. If not or you are in doubt, do more measurements to check how the arms compare or just change to measuring saddle to the pedal center. Should be obvious but also it should be said, we also need left to right matching as well as bike to bike matching. -- Ken
I just spent an hour comparing BB to saddle length and from peddle axel with crank arm parallel to seat post measurements and you nailed it. The bikes have different crank lengths and putting the crank arm in line with the seat post showed a measurable difference. I then compared left to right side of each bike and that was within a 64th. I did not get out on the bikes to test tonight but I will ride them tomorrow. Thanks again for you help with this aspect.
Frank.
Frank, using BB center between two bikes is only valid if the crank arms are the same length. If not or you are in doubt, do more measurements to check how the arms compare or just change to measuring saddle to the pedal center. Should be obvious but also it should be said, we also need left to right matching as well as bike to bike matching. -- Ken
I just spent an hour comparing BB to saddle length and from peddle axel with crank arm parallel to seat post measurements and you nailed it. The bikes have different crank lengths and putting the crank arm in line with the seat post showed a measurable difference. I then compared left to right side of each bike and that was within a 64th. I did not get out on the bikes to test tonight but I will ride them tomorrow. Thanks again for you help with this aspect.
Frank.