"The 33"-Road Bike Racing - Long legs, wide shoulders, short torso and TT fit

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guadzilla
12-06-10, 08:45 AM
I went and had a TT fit done recently but am not sure if that is the right position for me. I am very flexible and can ride for an hour on the drops with a flat back and 5" of saddle-handlebar drop.

However, I have long legs/very short torso. So for me, if I want to ride with a flat back (which, by itself, is perfectly fine), I have to do it in one of the following 2 positions:
1/ Elbows inside the knees (which is very uncomfortable - my rear shoulder muscles, along my shoulder blades, start to hurt within 30 seconds of being in this position)
2/ Elbows outside my knees (which puts them really wide/far out).

If my elbows are in line with the knees, my legs hit them.

Just had a fit session - a relatively low-tech one, in terms of no lasers/power meters/etc. but with a guy who does know his stuff and who's done a great fit for me for my road bike.

He set me up with a stupidly high stem - one that belongs on a hybrid. This is the only position that lets me have my elbows at a moderate width without banging into the elbow. My back is no longer perfectly flat but atleast this feels a bit comfy.

I havent done any rides in this fit yet, but wanted to check and see what some of you guys with similar body types are doing.

Do the shoulder muscles get used to being scrunched in? Will moving to ski bends, instead of S curves, help? HTFU/do weight training to strengthen this area? Or just ride this way for a while and see how the muscles react once they get used to this position?

TIA,
V.


king-tony
12-06-10, 09:17 AM
Having your elbows out so that your knees can go between them is not necessarily bad. It helps channel the air around your quads. For most people there is a sweet spot and without a tunnel there is no way to know for sure. Your shoulders can get used to almost any position. Light weights or resistance bands and exercising them every day will speed this up. Don't get too hung up on the flat back. While that is a good rule of thumb, your head position will probably have a bigger impact and your head/back interaction is what really matters. Without a tunnel, I would simply say get as low as you can in the front while still being able to generate power. Comfort is a relative term and I would not call any TT position I have ever been in comfortable, only tolerable. Finally, I have seen few people go through the tunnel who need S-Bend bars. Ski bends, or some variant, usually work better with most non-UCI compliant positions. But people like S-bends because they look good on the bike.

Dalai
12-06-10, 09:38 PM
If you have a PM you could try different positions and field test using either Chung Virtual Elevation method (used by the newly released Golden Cheetah - Aerolab) or the Regression model...


guadzilla
12-07-10, 03:59 AM
@Dalai - actually, I can do one better. I got an ibike iAero unit for a really good price and plan to use it as a head unit with PT wheels. This apparently will let me calculate actual CdA info.

@Tony - ok, that's somewhat comforting to know that arms wider than the ginormous guads wouldnt be the end of the world. I'm probably going to ride in a slightly more comfort-oriented position (either as set up currently, or lower but with arms outwards) for a bit, try to get used to it and then slowly work on making my position more and more aggressive. Any ideas on whether it would be better to have low back/wider arms config or higher back/narrower arms config as a starting point?

And some of it, I admit, is also a bit appearance-oriented. The TT bike looks stupid with the ridiculously high bars. My road bike has a greater saddle-to-handlebar drop, fer crying out loud!

V.

Racer Ex
12-07-10, 07:24 AM
Any ideas on whether it would be better to have low back/wider arms config or higher back/narrower arms config as a starting point?


The former is more likely to give you a lower CdA.

guadzilla
12-07-10, 07:54 AM
The former is more likely to give you a lower CdA.

:beer:

Thanks - will set it up that way.

V.

Nate552
12-07-10, 08:16 AM
:beer:

Thanks - will set it up that way.

V.

Yep, when in doubt, go as low as you can on the front.

carpediemracing
12-07-10, 10:37 AM
..ridiculously high bars.

Not sure what rules you need to follow but it would be interesting to check out the Superman position. It was illegalized after it was used to break the ultimate hour record. Apparently it utilizes quads more or something. I think the whole "using different muscles" excuse was more about what off-track assistance they used but I have no proof of that.


http://www.youtube.com/watch?v=9YBfEsy1xO8

The Italians totally rocked that year, demolished virtually everyone with the superman position and the bikes. Regardless of how, they were flying. They used bigger gears than normal (hence the slower start) but could go faster overall.


http://www.youtube.com/watch?v=NiM94C0nGW0
Of course you couldn't beat raw talent. Boardman on his adapted Lotus bike.

cdr

rruff
12-07-10, 11:32 AM
Not sure what rules you need to follow but it would be interesting to check out the Superman position.

That would be my recommendation as well. Even if you have to meet UCI rules on extension length, you should be able to get your elbows in front of your knees... unless you are really tall.

rruff
12-07-10, 11:39 AM
@Dalai - actually, I can do one better. I got an ibike iAero unit for a really good price and plan to use it as a head unit with PT wheels. This apparently will let me calculate actual CdA info.

Unfortunately it isn't that easy. Even if you manage to route the airspeed tube in a very clean area, any changes you make to position will still effect the readings of it... which means you need to do an extensive calibration with each position... which will probably still introduce error bars that are bigger than doing Chung alone. The iBike simply fluctuates too much both in slope and airspeed determination. You'll be able to get a decent estimate of your CdA but it won't be precise enough to pick out small changes.

guadzilla
12-07-10, 07:35 PM
That would be my recommendation as well. Even if you have to meet UCI rules on extension length, you should be able to get your elbows in front of your knees... unless you are really tall.

I can get my elbows in front of my knees, yes - but then my upper arms arent approx 90 degrees to my torso, they are stretced outwards at an obtuse angle. The fitter seemed to think that this wouldnt be a very comfy position, as it would be difficult for me to support my weight on my arms comfortably like this.

FWIW, I am 6'0" with a 35.4" PBH - so very short torso, very long legs.

@rruff - ah, I did not know that. Snap, there goes the "inexpensive access to a mobile windtunnel" :) Oh well, will check out the Chung method and give that a shot.

V.

rruff
12-07-10, 08:52 PM
Having your arms stretched out might not be super comfy, but Obree set the hour record that way. So long as you aren't doing 100 mile TTs you can probably adapt easily enough.

The iBike is still a nice head unit.

http://i35.tinypic.com/14w9esy.jpg

Quel
12-07-10, 09:18 PM
You said you had a TT fit done...with what as the starting point? A bike you own and rode all season? A bike you just bought? Without actually seeing any actual info I doubt anyone here can tell you too much. Could be a fixable fit problem, but maybe it would be best solved by a new bike with proper geometry for your body.

I might suggest reading some of the fit articles over on Slowtwitch.com. Their two big lumped bike fit categories are long/low and tall/narrow. Tall/narrow (taller height, shorter length) is considered better for short torso with long legs. Felt, Cervelo, and Kestrel are long/low, while Trek, Scott, Cannondale, and some others are tall/narrow.

See in particular: http://www.slowtwitch.com/Bike_Fit/Choosing_a_Tri_Bike_via_Stack_and_Reach/Long_and_low_short_and_narrow_613.html

Sorry for the tri nerdiness injection, but the site is good for TT stuff.

guadzilla
12-08-10, 10:16 AM
Having your arms stretched out might not be super comfy, but Obree set the hour record that way. So long as you aren't doing 100 mile TTs you can probably adapt easily enough.

True. A dose of HTFU never hurt, eh?

@Quel - This fit is for a new frameset and is my initial set-up. I plan to ride it for a season or so, see how I do and then have it re-done/optimized later. I merely want to get it set up into a good starting position for now.

I did read that Slowtwitch article. Several times, actually. Picked the frame (a Planet X Stealth) based on approximating a TT position on my road bike (sitting up on the saddle and estimating where my arms would be in a tuck), and for the most part, it seems fine.

It's not so much a specific problem per se - I am just not fully certain that the solution the fitter has found for me is the best one, that's all, and was trying to see what others who have a similar build as me do, in order to understand what my other options are. So far, I have 2: 1/ Lower/wider and 2/ Superman. Will give all 3 a try and see how it goes.

V.

Quel
12-08-10, 11:27 AM
Got any pictures? Frankly, sounds like you bought a frame that doesn't fit well if you are hitting your knees. But it could be something as easy as pushing the seat forward (which opens the hips) and getting a longer stem. I don't see why you need to settle for a compromise position just yet. You may have long legs/short torso, but not freakish, so you should be able to get a conventional fit somehow (though again, that could involve a different frame which probably isn't an option).

But of the two, superman should be faster, assuming you can hold it. Doesn't matter how slick your position is if you are sitting up half the time. And you shouldn't even have go to full on superman, just have your arms extended a bit to give your knees clearance.

rruff
12-08-10, 07:02 PM
Got any pictures? Frankly, sounds like you bought a frame that doesn't fit well if you are hitting your knees. But it could be something as easy as pushing the seat forward (which opens the hips) and getting a longer stem. I don't see why you need to settle for a compromise position just yet. You may have long legs/short torso, but not freakish, so you should be able to get a conventional fit somehow (though again, that could involve a different frame which probably isn't an option).

I doubt it is a frame issue... or at least it shouldn't be. You can get aerobars that allow an insane amount of adjustment.

The "knees hitting the forearms (or knees)" phenomena isn't unusual if you have long femurs and a short torso... and you want ~90 degree angle between your upper arm and torso. The only fixes for it are to put your knees inside or outside your elbows, or raise the elbows above the knees, or extend the reach. I think the last one is the best... but if you are tall and need to meet UCI regs, it's tough. In the photo of Obree above, I think he is even UCI legal, but used a rearward saddle position to achieve it.

guadzilla
12-08-10, 10:30 PM
I dont need to meet UCI regs, so that is one saving grace.

@Quel - the fitter's main diagnosis was that the pain in my shoulders was from too much pressure on my arms (which is true, esp when the arms are narrow). So he moved the seat a bit further back. I think if I move my arms wider, I can push the seat forward and open up my hips some more for sure. He was very opposed to that idea, but going by what I read here, it shouldnt be an issue.

I'll post photos of a couple of positions at the end of the month - am still limping from a piriformis injury today and flying tomorrow for a single day race and then a 7-day stage event.

V.