Patriot

Ok, Answer me this, because I have been through everything on both of my bikes, and just can't figure out what the problem is. I keep getting some knee pain when I ride one of my two bikes.

When I ride Trinity, I almost never have any trouble with knee pain. Matter of fact, I rode the 200+mi STP in one day, and everything got a little sore, EXCEPT my knees. Trinity has 175mm cranks, and an SLR saddle, carbon bars and Campt ergo shifters.

When I ride my Centurion, I regularly get knee pain (patella). Now, my Centurion has shorter cranks, 172.5mm, alloy bars, a Lookin Gel saddle, and aero brake levers w/DT shifters.

Now, geometry on both bikes is set up exactly the same with only a couple of varients that I cannot duplicate on the Centurion. One differance, is the bar height. The Centurion bars are 0.75" lower. The quill just won't go up high enough. I plan on getting a long quill stem for the rebuild. Saddle height, setback etc, is all exactly the same.

The other differance, is the crank length. Now, one would think I would have less problems with the shorter cranks on the Centurion. But, I keep getting some knee pain. I rode Trinity yesturday for 20mi, and my knees felt great, as usual. Sometimes, I feel a little stiffness, but never outright pain.

Today, on my commute to work, my knees felt ok, until about half way through, when I felt a twinge. After I got to work tonight, now they are feeling sore. I am going to have to take it very slow on the way home.

I am hoping that when I rebuild the Centurion next year, that it will be fixed, whatever the problem may be. I just don't know what.

Any takers?

cmcenroe

I don't really know, but I have knee pain every time I ride, also. Do you ride the same pedals on both machines?

Patriot

Yes, differant pedals. Both Look designs though. Cleat positions are the same. My Carbon bike I use the hard carbon soled shoes, and the Centurion I use the rec Exustar shoes. The shoes have always seemed fine.

What's funny, is when I first started riding over a year ago. I rode the Centurion all the time, and had no troubles. Only recently since I have started commuting. Actually it started in August, after I got back from being on vacation for two weeks. The pain seems to come and go.

Some days are good, some not so good.

clausen

Where are you measuring your saddle height from centre of the crank or the pedal? Could be the thickness of the soles in your two pairs of shoes. I know I use a lower cadence when in traffic compared to when I'm out in the country and that causes me some minor aches.

High Fist Shin

I'm not sure if this will help but it may be worth a shot.

I have two bikes I ride regularly and I was getting knee pain with one and not the other. I thought the problem was with the pedals and float because one was fixed and the other had 9 degrees of float. It was the fixed one that was giving me the trouble.

I switched out the shimano spd's for speedplay froggies and it seemed the problem went away. On rides of about 40 miles or so, no pain. Anything above that and the pain started to creep back it.

I decided to see my doctor and he refered me to a sports medicine doc to check my knee for me. I learned that the problem was flexibility in my right IT band and patella tendon. He gave me a group of stretches to do 3 times a day for 15 minutes each to try and loosen it up.

It's been almost 2 weeks since I started stretching more and the difference is amazing. It's like the pain was never there. I can ride the speedplays on long rides and there is no pain. My knee feels different and I can tell the difference as soon as I hit the first hill.

I offer this advise because it has been my experience that cyclist don't stretch enough and this can lead to problems.

I hope this helps you. Good luck.

Dante

SpongeDad

1. I would buy a cheap set of 175 cranks and see if that fixes the Centurion. Could be something as simple as higher torque, although you'd think you could modulate that.

2. I swear my Trek pedal position feels wider than the exact same pedals on my Merlin. You might want to measure the width. (When I got the Merlin, we spent a lot of time getting my left knee laterally lined up over my left foot, not just fore/aft/KOPS positioning). To the fitter's credit, he spotted the problem before I mentioned that my left knee occasionally twinges.)

3. Trinity is jealous and is smacking your knee at night a la Tonya Harding when you ride the Centurion.

4. When you pose, make sure you do on both the left and right side to maintain balanced development.

Grasschopper

Wait a min...if you have the same saddle height (c of BB to top of saddle) but different crank lengths then you effectivly have a different saddle height don't you?

Could this be a saddle height issue?

EURO

Me too. I had really bad knee problems (couldn't walk!), saw a physio who diagnosed IT band, and after a couple of weeks of HORRIBLE stretching and acupunture I'm great.

There are two things I would do - go and see a proper fitter with both of your bikes - the kind of guy who uses a laser pointer and LeWedges to make sure your leg is straight, and failing that go to a good sports physio.

Hipcycler

Three words:

Knee Replacement Surgery

I mean, come on, titanium in my bone and I'm a happy man.
Posing right down to the X-ray....I'm as OCP as anyone could be!

TallRider

I doubt that it's your saddle height - you seem to know your stuff on bikes and setup. I've thought of two factors that differ between the bikes, that might explain what's going on.
(a) Type of riding: I understand you use the Centurion mostly as a commuter, and "Trinity" for your "real" rides. Commute riding has different demands, and I tend to use a different riding style to boot. Does your cadence vary? Are you standing to sprint more, heading away from stoplights? (Keep in mind that in the cold weather, this will be harder on you than in summertime.) Any other diffs in riding style?
(2) Weight. I doubt this is the culprit, but I seem to remember that Trinity weighs 16# and the Centurion 28# - right? This could matter slightly, when tied in with differences in riding style. You're adapted for sprinting away on a lighter bike, this form isn't perfectly adapted to a 12# heavier bike, but it's only going to mess with your knees in the cold?

55/Rad

How's this for a theory....

You only ride Trinity when it's nice outside. Warm. Middle of the day fun rides.
You ride the Centurion to commute in the cold, rain, dark of night, grind-the-knee stuff.

55/Rad

Hipcycler

Well duh!
There it is...Dr. Rad has figured it out with common sense.
Now bill him $842.76 so that his insurance can cover $100 of it and he has to pay you the rest direct.

2manybikes

Higher gearing could do it. A higher first gear?

Just a bumpier ride could do it. Anything that is stiffer. From the tires up to the shoes.
More small vibrations.

If you wear more warm clothing on one bike the seat height can change due to more padding.

If you ride the Centurion in the cold of the morning the temperature could do it. You may have to warm up more carefully in the morning. Or you may have to insulate your legs more. You just may be stiffer in the morning.

A different width from pedal to pedal. Q factor

A saddle with different shape edges next to your legs can position your legs in a different place. They could be closer together, farther apart, more forward or more to the rear.

How about saddle forward or backward related to the BB ? You have a Dave Scott Ironman right? It's a tri bike with a different seat post angle I think. That could easily do it.

Jim Bonnet

Seat height. I have the same problem sometimes when switching bikes with different crank lengths. Your saddle is not at the same height if you measure centerBB to seat clamp on different crank lengths.

--jim

popeye

"
I decided to see my doctor and he refered me to a sports medicine doc to check my knee for me. I learned that the problem was flexibility in my right IT band and patella tendon. He gave me a group of stretches to do 3 times a day for 15 minutes each to try and loosen it up."

Could you please describe the exercises.

jazzy_cyclist

I had some problems with ITB last summer. After some stretching, it went away, but I have to be very vigilant because my hamstrings and quads both get pretty tight. When things get too tight, then the bony parts of your knees start rubbing against that tissue and get inflamed. As I understand it, the ITB is usually on the outside of the knee (it was for me anyway).

So the next question is why did I get it on one side? Well, I only noticed yesterday in a session with a PT guy that for some reason my left leg swings out more than my right, stressing it more. No real reason for it to do that - just something I have to consciously work on. Anyway, the point being that Q-factor might be something worth looking at.

If you can get someone to measure your leg angle when your leg is extended, not extending more than 25 degrees can definitely stress the knee (angle needs to be less). This is seat height issue. Also, picture the saddle being *way* back behind the pedals -- that would stress your knees also, wouldn't it? If these things are the same, then I'm baffled too.

jfmckenna

yes that is indeed a problem. raise the saddle.

Patriot

Well, I have ruled out a couple things.

1. Saddle height. I have experiemnted here on numerous ocassions compensating for the differant crank lengths, and setback, with no result.

2. Cold weather. Well, I ride Trinity in the winter quite often as well. Sometimes, even in the rain. Did I say that? I mean... um... only when it's 85F and no wind. Yeah, that's it.
Although, admittedly, it may behouve me to spend more time warming up before I get the lead out on my commute. That could easily be a factor in cold weather and with the heavier bike combined. So, Rads theory is with merit.

I am leaning towards Rad and timcupery's line of thinking. The bike is a good 12# heavier, and I do alot more start and stop riding in the city. I stand and sprint much more often, even when climbing small rollers. I have noticed it happens mainly when standing, or when I push hard and my knees get a little cocked outward, instead of inward towards the top tube. I guess this happens more often because I am fighting the weight of the machine much more so than with Trinity.
I am hoping when I rebuild the bike with the bigger cranks and new wheels, that I can drop the weight by at least 2 pounds or more with a new group, and hopfully that will help a little.

Oh, and btw, Trinity is sub 15# (sans accessories). I just want to clear that up. I wouldn't want Trinity to have a complex, thinking it was overweight or anything.

I am also thinking that a good stretching regimine may help aleviate some of the problems. It can't hurt. Besides, how am I supposed to get better at cycling if my knees can only go so far? I have to figure out how to improve without ruining the goods.
Sorry Hip. I like titanium, but would prefer to keep it on the bike, not in my legs.

Aonbay

I concur with this deduction!!!!!!!

simplyred

Patriot,
I think your knees want to ride that magic carpet called Ti

Honestly though, the above postings seem to pretty much sum up why you hurt. Another suggestion is to really keep in check the Ti geometry to Trinity's so you don't have another body part in pain when busting out your new ride..

-simplyred

Mojo GoGo

I have the same problem with my Allez and Madone and I just came to accept that it's crank length. Sure the Allez is heavier and has more limited gearing but my legs will get achy on the Madone but will be outright sore with the Allez - and this is from a guy who didn't used to think crank length mattered...

High Fist Shin

The best part about the stretching regimine is that it's free and you can start right away. The weight of the bikes may factor into your troubles but I also noticed some other things after I started the stretching...

When I wore lighter shoes, like casual dress shoes, my knees would start to bother me a little at the end of the day. If I wore heavier shoes or boots, no knee pain.

After the stretching, I can wear either pair and I don't have a problem.

The other thing to consider would be that your muscles and joints are used to pushing around Trinity at 15#. Then you go and jump on the commuter and the weight difference is putting extra stain on the joints and muscles. If your ITB is tight, it will pull your knee out of alignment on the upstoke causing pain. This was my problem.

I also changed my foot and knee position while riding a little. I brought my knees in tighter to the top tube and brought my toes in and my heels out a little. Kind of pigeon toed if you know what I mean. This seemed to be the fix I was looking for along with the stretching.

I hope this helps you Mr. Pres. I hate to see anyone going through this because I've been there and I know it hurts.

Dante

mrt10x

I broke my back 15 years ago, for the next 8 or so years I struggled with daily and sometimes debilitating back pain, imagine that. It got so bad around 1999 that myself and my doctor, based upon MRI, decided it was time for surgery. Luckily, although I resented it at the time, the Marine Corps (actually Navy doctors) insisted that I go through 4 months of physical therapy before the surgery would be approved. As part of this therapy they gave me a book called "Stretching" I was forced to stretch three times a day for 15-30 minutes at a time... miracle of miracles,, back pain went away.. and has stayed away for the last 6 years. More on topic, a simple switch last year from 04 Asics to 05 Asics, same model OBTW, caused my first ever ITB pain. "Stretching" to the rescue, adding a simple ITB stretch, basically bending at the waist to touch your toes, but with one leg crossed in front of the other, and the ITB pain went away.
Bottom line, stretch 15 minutes in the morning when you wake up, and MOST IMPORTANT stretch 15 minutes before you go to bed. This pre-rack stretch is amazing in its benefits. Find it here, it has sport specific stretching routines.
https://search.barnesandnoble.com/booksearch/isbnInquiry.asp?userid=a11X1neA8Y&isbn=0936070226&itm=1]https://search.barnesandnoble.com/boo...36070226&itm=1[/URL]
OBTW I also like the theory that your different saddle widths might be causing your stroke to vary slightly. ITBs are extremely sensitive to changes in repetitive motions.

bob the nailer

doubt saddle height would cause knee issues. you don't say what kind of look cleats you have, and if they have any float, if not, get some with float, will prolly fix the issue.

wagathon

This sounds very possible. If you do straight-leg with heel on the pedal method of approximating the saddle height, the saddle should be lower with 175s. However, for me, having the wrong saddle height has a bigger effect on the hammys than the patella.