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Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 3:33 pm
by Xplora
I had to readjust my seat up recently after it was about an inch too low and my knees were crapping out badly. The handlebars felt OK and the seat position felt OK. Since going up the hoods feel too far away and I'm not really getting my abs into the ride enough anymore. I'm trying to figure out what has changed to make me feel so much less comfortable, and what to do to fix it. I'm starting to think the stem is too long, but I'm not really feeling like I'm sitting right either. The outside of my right knee was giving me a lot of grief (still is, really) because I unclip with that foot, what seems to be the solution? It's a 59cm frame but I'm not that short. Am I? :oops:

Re: Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 4:02 pm
by sogood
There'll always be a period of discomfort and unfamiliarity after a change in the fit. And 1" is a big change. So it may take time for you to get used to the new position, even if it's the "ideal" fit. Otherwise the solution to this is to read more on the net and there are lots of basic but good articles on bike fitting. If you are not up to it, then the next option is to pay someone knowledgeable to look it over for you.

A side on photo of you on the bike with pedal at the lowest point can be quite useful for fellow members to comment.

One question though, how did you determine the "correct" saddle height?

Re: Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 4:40 pm
by trailgumby
Better even than a side-on shot would be video about 30 seconds or so each from each side of you and front and back pedalling seated on a trainer under significant load, after warming up and getting hot.

Pedalling is a dynamic thing, and how you pedal under load can be very different to when you're soft-pedalling, and with due respect to sogood, just sitting on the bike won't tell us a whole lot about what's going on with your action.

I know it is the case for me, and I'm still a work in progress with getting myself and my assymetric action (tend to drop the left hip) sorted out.

Re: Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 4:56 pm
by nayfen
In regards to the knee pain

Assuming the bike is correct size and you have the seat position set to the right height. This can be determined with something like bike fit calculator try these couple of points.

Fore & aft seat position
Adjusting position: Loosen seat bolt to slide seat back on its rails as far as it will go. Re-tighten seat bolt. Make a plumb bob – tie a key or squeeze a glob of "Blu-tak" to the end of a 1.5m long piece of string. On a level surface, lean the bike against the wall and sit in your normal riding position with feet at the 3 o'clock- 9 o'clock position (i.e. cranks parallel to the ground). Have someone drop the plumb bob down from the tibial tuberosity on the forward knee (this is the small bump just below the knee-cap) to the floor in between the cranks and frame. Position the foot parallel to the floor. Adjust saddle position forward until plumb line falls directly through or just slightly (1-2 cm) behind the centre of the pedal axle. Re-tighten the seat bolt. Check to see that the saddle is perfectly level. Check this with a spirit level or lean bike against a brick wall and check against the brick lines (make sure floor is level).

Feet position
If no improvements are made with seat adjustments look at feet position on pedal. Observe if toes point in or out. This can cause aggravation to the knees. Adjustments will need to be made to the Qfactor. Easiest way is moving the cleat position on the base of shoe. The fore/aft position of the foot can manipulate the muscle bias between calf and quad sometimes eliminating knee pain. You could try a cleat with larger degree of float. This will provide a greater range of movement and give the knee some extra scope. Also try loosening the cleat tension so that it easier to release from pedals. This may help a little.

As far as riding in the hoods & feeling stretched out. Loosen the handle bar at the stem. Rotate the bar towards the seat a few degrees at a time. Each time hopping on and going for quick spin. If it feels more comfortable with the hoods closer, you have three options leave bars in new position problem solved. 2. Put bars back in original position slide brifters up bars and redo bar tape. 3 buy shorter stem.

Re: Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 9:03 pm
by Xplora
I tend to just go with whatever feels comfortable as far as fit goes. If I can't straighten my leg out then it's too low. I know I shouldn't completely straighten, but if its too low you don't survive the climbs. I realised that I think my seat is too far forward now, because I'm not using my core to "sit" anymore, it's all going through the wrists. I think it was less of an issue when the seat was lower because my torso weight compared to the legs was behind the ankles more (which makes sense, your balance point leaning forward sitting on a chair is different to when you stand). I'm a bit interested in dropping the bars as well to get some comfort on the hoods, and epic pace on the drops. I definitely get the impression that my Kona isn't designed to pleb away hybrid bike style :mrgreen:

I'll probably have to invest in a fitting at some point, I'm commuting too far to just let it go. If you can a few bucks though...

Re: Bike fit impacts on comfort and health?

Posted: Fri Jun 24, 2011 9:16 pm
by trailgumby
25-35 degree knee bend with foot at bottom of stroke is what works for most folks. How that translates to seat height depends on whether you are a heel dipper, a toe dipper, or somewhere in between. I tend to be a heel dipper at the bottom of the stroke these days, although I started as a toe dipper.

Initially the lower seat felt quite uncomfortable when I first tried it, so I put it back straight away. However, but after my bad crash and an experience with a gradually slipping replacement carbon seatpost when I returned to commuting a couple of months later, I found myself with a lower seat height and no loss of power on the climbs. So that demonstrated to me that a lower seat could work.

Once I fixed the slipping with some Ritchey Liquid Torque I left it just below the middle of the range, and no more sore back. Ended up being about 1.7cm lower than where i used to run it.

Re: Bike fit impacts on comfort and health?

Posted: Sat Jun 25, 2011 9:07 am
by Xplora
I think the part I don't like is the lack of power while in the seat, I don't like standing up much LOL but I'll look at the lower seat. 25 degrees sounds way too much to me though. I guess my understanding is that you stand up to get power so therefore it seems reasonable that the closer you are to standing, the better. Allowing for the fact your knees don't extend perfectly etc. I do prefer to ride as fast as practical (limits of safety and my lungs) so the more intense position feels better most of the time. I'll try and play aruond with it this weekend if I don't collapse from flu. So bad to ride home with the chills :shock:

Re: Bike fit impacts on comfort and health?

Posted: Sat Jun 25, 2011 5:47 pm
by sogood
If you are really worried about power, then you better fork out a few hundred buck for a professional fit. Otherwise just do the simple straight leg heel-to-pedal test for your saddle height and go from there. You'll be in close enough ball park for general needs.

Re: Bike fit impacts on comfort and health?

Posted: Sun Jun 26, 2011 2:05 pm
by Xplora
I don't know if I'm "worried about power" as much as "addicted to power". I bought my Honky Inc with the drops because my wife's flatbar just wasn't cutting it. It's set up for plebbing, and I don't pleb unless I'm knackered (which is fairly common, given I ride as hard as I can). The constant aggressive riding attacks the legs eventually.

Random aside, I've lost 10% of my peak weight since starting to ride 12 months ago. I only weigh 155 lbs or so, but damn!

Re: Bike fit impacts on comfort and health?

Posted: Fri Jul 08, 2011 3:17 pm
by BigLexi
trailgumby wrote:Pedalling is a dynamic thing, and how you pedal under load can be very different to when you're soft-pedalling, and with due respect to sogood, just sitting on the bike won't tell us a whole lot about what's going on with your action.
Agree...my hips tend to drop a little after 5-10 minutes of pedalling and what felt a little too high all of a sudden feels perfect (like I almost need to slide the seat up again...just a little).

Re: Bike fit impacts on comfort and health?

Posted: Thu Jul 14, 2011 6:07 pm
by Xplora
My wife suggested that I needed to move the seat forward, rather than up and back. I tried sitting a bit forward today and ended up feeling my upper quads and abs pedalling for the first time in ages. She was right :oops: I've been going further and further away and it's been killing my legs. I think I've been in denial about how big I really am on this bike :lol: Going to adjust the seat forward tonight and wait for my strained right knee to recover. 8)

Bike fit impacts on comfort and health?

Posted: Thu Jul 14, 2011 8:14 pm
by Redbull
How tall are you?

59cm frame is fairly big and if you are 155lbs then you should be a tall thin streak :).

I'm 193cm and I ride a large compact frame and a 60cm standard.

Re: Bike fit impacts on comfort and health?

Posted: Fri Jul 15, 2011 8:25 am
by Xplora
I'm 185 high, 6'1" and a bit in the old language. Hell yeah I'm thin. Even thinner since I've been riding all the time. I'm just about excited to move the seat forward if it means riding is painless again, I can focus on HTFU rather than "ouch, I think I need antinflammatories" 8)

Re: Bike fit impacts on comfort and health?

Posted: Mon Jul 18, 2011 1:22 pm
by Gerardthekiwi
I've recently had a "proper" bike fit, lasting 2 hours and resulting in a lower seat height, wedge under one cleat, longer stem plus custom foot beds for shoes.

Craig also identified that - being knock-kneed - I needed a longer pedal axle on the LHS.

My advice would be to get a fit like this done, by someone with lots of experience who uses technology to the max (laser tracking, videoing etc).

I wish I'd had it done sooner and would recommend it to new and old cyclists alike.

Re: Bike fit impacts on comfort and health?

Posted: Tue Jul 26, 2011 6:12 pm
by Xplora
Adjusted my right cleat so the shoe was closer to the crank. Feeling quite a bit better now... let's see what the week holds?