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Q-Factor and IT Band Friction Syndrome: how to fix it? (long)(14 posts)

Q-Factor and IT Band Friction Syndrome: how to fix it? (long)JS Haiku Shop
Feb 21, 2003 9:48 AM
this year i've not ridden the single speed very much.

in november 2001 i switched from riding frames with double and triple chainrings (mostly triple), to riding almost solely my surly steamroller, a track/fixie frame setup with a freewheel and a single front chainring. to be clear, it's not a converted geared bike--in other words, no removed chainrings from a double or triple, just a one-chainring crankarm.

my ITBFS problems started after 3-4 months of riding the SS, and i was off the bike and in physical therapy (twice weekly) for ~2 months. the problem was isolated to my right knee (drive side). they continually claimed it was not a physical problem (cause), but "biomechanical", citing the setup of the bike or cleat (sports PT).

as i've not ridden the ss bike much since march 2002, and PT was "successful", no problems to report. however, i got out for a 20-miler yesterday on the ss and came back with a little "twinge" in my knee--not a limiter, but a sign of things to come, if not careful.

supporing info: i was using mtb spd pedals on the ss, and swapped to Look pedals, which seemed to alleviate the problems some. switching BACK to mtb spd pedals worsened it. however, i can ride either set of pedals on the frames built with double or triple chainrings. with exception of virtual (total) tt length/length of cockpit, all bikes are setup identically, and i'm using the same shoes.

my line of thought is this: assuming Q-Factor is the distance between the bb shell and the center of the cleat receptor in clipless pedals, my steamroller has a smaller q-factor (yet to be measured) than the others, causing my lower leg to bend that much further toward the center of the bike, stretching the IT Band across the outside of the knee. spd pedals make it worse since the platform is smaller, making the q-factor that much less; look pedals not quite as bad (larger cleat and platform), but still problematic.

questions are:

is the correct way to measure q-factor to take the distance from the outer edge of the drive-side bb shell to the center of the pedal cleat receptor?

assuming this is the problem, how do i shim or add spacers to the pedal spindle to increase the q-factor to mimic the other bikes?

thanks in advance.

-J
Q-Factorsoup
Feb 21, 2003 10:04 AM
Sheldon calls it "tread"(new to me), measures it as the lateral distance between pedal attachment points, and seems to think the narrower the better:

http://www.sheldonbrown.com/gloss_tp-z.html#tread

I'm no doctor, but I would think that ITBS would show up quicker than 3-4 months after starting the suspect activity. Was/is there anything else going on-- increased intensity, lower cadence, more climbing, etc. that might have casued an injury that never really went away? When you say PT was sucessful, what do you mean? We're you able to ride your other bikes abosolutely pain free?

Knees are weird. Good luck.

soup
Q-FactorSpunout
Feb 21, 2003 10:10 AM
I'm a bit knock-kneed in that my knees brush the top tube on the way up. I just pushed my Look cleats inward on my shoes, getting 5mm per side. No more knee pain.

Time pedals have adjustable Q-Factor. Washers on your pedal threads can buy a few mm, not too much though!. A wider BB will help.

I think everybody is different, and maybe your PT can calculate your 'tread'. Measure up your bike, and see if you are close.
re: look cleatsJS Haiku Shop
Feb 21, 2003 10:19 AM
my look cleats are already as far back and as far "inboard" as possible.

thanks for your response!
Q-FactorJS Haiku Shop
Feb 21, 2003 10:18 AM
late november 2001 i did some skiing (first time) and left the (bunny) slopes with some pain in my right knee. this took several weeks to go away.

no increased intensity, but increased spinning, yes. i changed to a smaller freewheel (higher gear) in summer 2002, so the increased "intensity" wasn't noticed until after the ITBFS had come & gone.

before posting, i looked up sheldon's definition of "Q Factor", and it didn't mean what i indicated in this post. however, i've read Q Factor many times in the past as the distance from foot to center of frame, so i figured it best to use that term than another.

thanks for your response.
I too am VERY interested in the responses to this postKristin
Feb 21, 2003 10:10 AM
J- Our ITBS issues seem to be very similar. I was riding SPD's on the DeBernardi, and even after laying off for 6 months the ITBS came back in the spring. I too swapped to Look Pedals and had much less trouble. I did have a twinge once myself even on the new pedals, but it didn't progress like it would on the old pedals. I haven't really had a real hard ride on the Looks' yet, but I'm cautiously hopeful. Good post.
red or black cleats?JS Haiku Shop
Feb 21, 2003 10:21 AM
I was using the black ones, switched to the red ones at the advice of the PT, and developed some other problems--patellar tendonitis (actually ligament, no?). seems the float made for much more play in the act of getting unclipped, and not only did that not resolve my problems, it added another one. going back to the black cleats cleared that one up immediately.
The red ones of courseKristin
Feb 21, 2003 10:41 AM
The black ones would not match my shoes, and that would simply not do. Thats an interesting thought...usually they say to go with more float. I should also mention, the local racer/shop manager who recommended the Looks suggested that some of the problems could be caused by the face the the SPD's (mine were shimano) allow some up and down float which could be bad for long steady distance types of riding.
There are several options,djg
Feb 21, 2003 10:58 AM
although I'd be wary of over-the-net diagnoses and prescriptions. If you have real problems, it's best to consult a real doctor, and to do it in person.

How you measure q-factor really doesn't matter, as long as you measure consistently. You know that you have different setups. Pick a metric and find the difference. Whether that difference explains your problems is not something I can tell you.

Andy Pruitt's medical guide for cyclists has some discussion of knee issues (including i.t.) and q-factor. It's pretty clear and I found it to be a helpful starting place. OTOH, it's not terribly detailed (and, although he's an experienced cycling trainer, "Dr." Pruitt is really just an Ed.D.).

Personally, I found it very helpful to increase my q-factor. I did this by a combination of cleat movement and the use of Look CX-7 pedals, which have an ajustable q-factor (within a certain range). I believe that the new Time pedals also have some (albeit maybe less) adjustability. Other folks use washers. All of these options give you a certain range of adjustment, which may or may not be what you need.

If you play around with this, play around gradually and be careful. Posting for a sports med doc or a physio with cycling specific experience in your area may really be worth your while.

Good luck.
thanks, much appreciated! nmJS Haiku Shop
Feb 21, 2003 11:02 AM
re: Q-Factor and IT Band Friction Syndrome: how to fix it? (long)SlowPokey
Feb 21, 2003 6:22 PM
J
I have been having IT band syndrome for half a decade now.

Narrow Q-factor definetely hurts me. For my fixed, I used a longer BB and ran the chain on the inside ring of my double.

For IT band, I have had really good luck with orthotics. My arches are so high (how high are they), my ped. had never seen such bad suplination.

The orthotics I have been using for the past 4 years have helped a lot.

I have also stopped riding my fixed and ride triples on both rode and MT. The extra Q seems to fix my problems.

My two cents...

SlowPokey
re: Q-Factor and IT Band Friction Syndrome: how to fix it? (long)Fignons_ponytail
Feb 21, 2003 7:04 PM
I also have q-factor related knee pains that are brought on by narrower q-factors. I'm leery of putting a washer in between the pedal spindle and crankarm, although this has helped me in the past and I use it currently as well. In the past I've also used Phil Wood bottom brackets in a longer spindle (still symmetrical, though) and will probably do this on my current ride. I have a C-Record crankset that uses a 111mm bottom bracket spindle, but will probably order the Phil Wood in a 115 when I replace my bottom bracket this spring. It will skew the chain line 2mm, but that should not be too bad even on my current 10 speed setup and it will allow me to remove the washers I'm currently using.
carbon pro vs. Ultegra125lb
Feb 21, 2003 8:08 PM
I switched from an Ultegra 170 to Cabon pro 172.5's and the problems started. the q factor is different between the two cranks, I'm working on switching back to 170's. I had to adjust my cleats (speedplay x2 pedals) forward towards my toes and outboard, away from the bike center. I'm also bow-legged and spaced the cleatbolt inboard, to compensate for the uneven pressure on the pedals, its helped a lot. Now the pain doesn't kick in until 40-60 miles, but shorter sub 40 mile rides at top speed are ok.

i used to use spd's, i will never use them again, the pain was unbearable. the speedplays are doing the trick, but my rides are getting longer and i need to find a fullproof pedal, bb, crank, cleat set up.

also consider a pro fit at the local shop for around $75
thanks, all...JS Haiku Shop
Feb 24, 2003 7:42 AM
i'm going to measure it out (busy weekend, no time yet) and use some washers as spacers at least for now, and will report back.

-J