weird fit (?) issue...adductor cramps

[dookie]

i've been wobblenaught fit on my primary gearie (about a year ago) by a guy with tons of experience with the system and elite riders. my self-diagnosis was surprisingly close to his numbers. anyway, bike feels great.

and i've used as much precision as i can muster to copy the fit to my other bikes. running the same saddle everywhere eliminates some of the uncertainties, and a laser plumb-line/level is the absolute bomb for this task. i would say that i have the saddle/BB relationship on all the others within +/- 1mm of the model bike in every direction.

so the issue is with my fixed-gear. it, and only it, gives me (sometimes wicked) adductor cramps when climbing seated. i can run the same gear on another bike and do the same no-shifting seated climb without issue. stretching a bit usually does the trick, but it sucks to have to stop the bike to do so.

the saddle to bar distance on the fix is a bit shorter than the model (see my WTT X2 post in the classifieds), but i have yet another bike that is even shorter and does not cause issues. q-factor? centaur carbon square tapers on the fix, UT on the model. i don't see how it could be a fixed vs. free issue, as it only happens during seated climbs where i'm applying (forward) power regardless of drivetrain.

so what gives? any ideas?

[SoCalSteve]

i've been wobblenaught fit on my primary gearie (about a year ago) by a guy with tons of experience with the system and elite riders. my self-diagnosis was surprisingly close to his numbers. anyway, bike feels great.

and i've used as much precision as i can muster to copy the fit to my other bikes. running the same saddle everywhere eliminates some of the uncertainties, and a laser plumb-line/level is the absolute bomb for this task. i would say that i have the saddle/BB relationship on all the others within +/- 1mm of the model bike in every direction.

so the issue is with my fixed-gear. it, and only it, gives me (sometimes wicked) adductor cramps when climbing seated. i can run the same gear on another bike and do the same no-shifting seated climb without issue. stretching a bit usually does the trick, but it sucks to have to stop the bike to do so.

the saddle to bar distance on the fix is a bit shorter than the model (see my WTT X2 post in the classifieds), but i have yet another bike that is even shorter and does not cause issues. q-factor? centaur carbon square tapers on the fix, UT on the model. i don't see how it could be a fixed vs. free issue, as it only happens during seated climbs where i'm applying (forward) power regardless of drivetrain.

so what gives? any ideas?

Sorry for the thread drift, but...

Please explain how this works and how you do this.

I have more than a few bikes and I use the same saddle on all of them.

Thanks,

Curious in Los Angeles :bike:

[rustychisel]

how long you been riding fixed?

are you using the same shoes/pedals?

[edit] oh yeah, a third question. what's an adductor? (maybe you need adductor tape) :banana: :banana:

no-one expects the Spanish Inquisition

[dookie]

how long you been riding fixed?

are you using the same shoes/pedals?

[edit] oh yeah, a third question. what's an adductor? (maybe you need adductor tape) :banana: :banana:

no-one expects the Spanish Inquisition

been fixed for several years, including many centuries (some with 5-6k vertical)...not new to it. drop bars & brakes & all that.

shoes/pedals are identical across all bikes.

adductors are the upper inner thigh muscles, primarily responsible for pulling the knees together. ever 'pulled your groin'? that's the adductors.
like this. (http://en.wikipedia.org/wiki/Adductor_muscles_of_the_hip)

[dookie]

Please explain how this works and how you do this.

i'm assuming that you can match vertical / level adjustments and it's only the fore/aft that is a mystery?

if so...here's what i do to match fore/aft (pretty simple, actually):

wobblenaught uses the widest point of the saddle as their reference point (which can be a bit tricky to find without calipers), but is really only needed if you've got different saddles or if you're starting from scratch and trying to position the first saddle to their numbers. if you've got a model bike and an identical saddle on another, any consistent reference point will work...so pick an easy one.

first, support & level the model bike...a wind trainer & front wheel chock is perfect. i use the wheel axles as my level reference. they should be the same height off the floor.

next, note vertical & level adjustments of the saddle. i run my saddles as close to dead level as the seatpost clamp will allow, so i use an old fashioned bubble level here. fancier tools are available, if you like toys or out of level saddles...digital levels w/angle readouts.

i had been doing this next step with a plumb bob on a string but found it very hard to be precise as the bob is never completely stationary (especially when i keep bumping it), the frame interferes with it, and it doesn't work in an upward direction (for the bars)...so i splurged on a $40 laser at home depot. now's the time to fire it up...be sure to make laser noises. psheeew! psheeew!

make sure it's firing roughly square to the bike and put the vertical line (or your string) on your saddle reference point, then carefully measure the (level) horizontal distance from the center of the BB spindle to your line. my exact procedure is to use a ruled 4ft bubble level and set it on something high enough to hold it at BB height (a paint can), then i can make sure it's level and slide it fore/aft to put the BB on a convenient starting point. sucks trying to hold it level and read it at the same time.

you can use exactly the same procedure to measure bar reach...put the level on the saddle and the laser line on the center of the bar flats and carefully measure the (level) horizontal distance from the saddle reference point to your line.

finally, measure saddle height to floor and bar tops to floor and subtract. there's your drop.

swap bikes & repeat, matching the numbers you just measured. set the saddle first, then see where the bars are in relation. keep in mind that vertical adjustments to saddle/bars also moves them horizontally, so do vertical first.

make sense?

[SoCalSteve]

i'm assuming that you can match vertical / level adjustments and it's only the fore/aft that is a mystery?

if so...here's what i do to match fore/aft (pretty simple, actually):

wobblenaught uses the widest point of the saddle as their reference point (which can be a bit tricky to find without calipers), but is really only needed if you've got different saddles or if you're starting from scratch and trying to position the first saddle to their numbers. if you've got a model bike and an identical saddle on another, any consistent reference point will work...so pick an easy one.

first, support & level the model bike...a wind trainer & front wheel chock is perfect. i use the wheel axles as my level reference. they should be the same height off the floor.

next, note vertical & level adjustments of the saddle. i run my saddles as close to dead level as the seatpost clamp will allow, so i use an old fashioned bubble level here. fancier tools are available, if you like toys or out of level saddles...digital levels w/angle readouts.

i had been doing this next step with a plumb bob on a string but found it very hard to be precise as the bob is never completely stationary (especially when i keep bumping it), the frame interferes with it, and it doesn't work in an upward direction (for the bars)...so i splurged on a $40 laser at home depot. now's the time to fire it up...be sure to make laser noises. psheeew! psheeew!

make sure it's firing roughly square to the bike and put the vertical line (or your string) on your saddle reference point, then carefully measure the (level) horizontal distance from the center of the BB spindle to your line. my exact procedure is to use a ruled 4ft bubble level and set it on something high enough to hold it at BB height (a paint can), then i can make sure it's level and slide it fore/aft to put the BB on a convenient starting point. sucks trying to hold it level and read it at the same time.

you can use exactly the same procedure to measure bar reach...put the level on the saddle and the laser line on the center of the bar flats and carefully measure the (level) horizontal distance from the saddle reference point to your line.

finally, measure saddle height to floor and bar tops to floor and subtract. there's your drop.

swap bikes & repeat, matching the numbers you just measured. set the saddle first, then see where the bars are in relation. keep in mind that vertical adjustments to saddle/bars also moves them horizontally, so do vertical first.

make sense?

Yes, it all makes 99.9% perfect sense!

Except for one thing (the .1%): How do you know that the plumb bob is "square" to the bike? Does it have a level built in it? If so, then it makes 100% sense.

Thanks for the great explanation!

Steve

[markie]

On a possibly related note...

I notice my inner thighs hurt after flailing the cranks around at 180rpm on descents....

Perhaps your abductors are worked already from spinning out on the descent and then the climb finishes them off?

[dookie]

How do you know that the plumb bob is "square" to the bike?

i suppose you could use a framers' square to ensure the laser line was exactly perpendicular to the centerline of the top tube, but i just eyeball it...

think about the lateral (ie: perpendicular to the bike) horizontal distance between the laser/ruler contact point and the laser/saddle contact point...an inch? less? whatever...relatively small. if the laser is several feet from the bike, you'd have to be dramatically out of square to produce a significant difference in the longitudinal horizontal distance between the same points, and that's what we're counting on to be exactly zero.

a few other notes:
- leveling the bike via axle to floor measurements assumes a level floor!
- i use the laser line as a reference when measuring saddle and bar to floor, to make sure i'm dead vertical.
- be sure to tell the wife the laser was bought for hanging pictures/shelves/etc competently (and without marking up the walls)...works beautifully for that too.

[dookie]

Perhaps your abductors are worked already from spinning out on the descent and then the climb finishes them off?

i hear you re: descents, but my discomfort starts almost immediately...not sure the spins are the root cause, but certainly an aggravator.

[rustychisel]

hmmm, an interesting one. I got nothing of any real help, but suspect this might come from being tensed and 'crabbing' on the bike rather than loose and easy pedalling. I've seen people who always seem ready to hit reverse gear on their fixed, as though they're anticipating the flywheel effect - you see it on the track a lot because new riders are worried about other bikes in close proximity. Make any sense?