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Bike Fit Numbers: 650 or no?

Hi all,

I was fit back in October for a tri bike using the retul system.  Here are the measurements:

saddle height: 668mm

saddle setbak, -22mm

saddle angle: -3 deg

eff. seat tube angle: 78 deg

grip angle: 50 deg

grip width: 100mm

frame stack: 519mm

frame reach: 350mm

handlebar reach: 448mm

handlebar drop: -60mm

arm pad reach: 343 mm

arm pad drop: -18mm

grip reach: 624 mm

grip drop: 65mm

arm pad to grip reach: 281mm

bb to grip reach: 602mm

arm pad width: 207mm

handlebar stack: 577mm

handlebar reach: 427mm

 

OK, that was probably more info than we needed, but I'm not sure what numbers (besides stack and reach) might be helpful. I am wondering if I am an obvious candidate for 650 wheals or not?  My fitter, who I honestly trust a ton, says he knows dan from slowtwitch would advise putting me on one, but he said he personally could go either way with it.   Right now I have a Look 700c and I've had one instance where I almost ate it because of toe overlap, but that could also be attributed to my own user error.  

Right now, I have been waiting for a Felt DA 48cm w/650, which my fitter says he has gotten word that he can get me one, but not until the end of march. The date keeps getting pushed back, not his fault, he's just telling me what they are telling him. But he's been assured he's got a 48cm coming our way, umm once they actually mold it i guess... Anyway, I'm getting a little scared that this won't pan out. I like the Blue bikes, but they only come in 700. 

So given my numbers, would I fit well on a Felt and a Blue (my fitter says yes)? Is there another bike that you would recommend?  My HIM is mid-July and would LOVE to actually be on a tri bike for it.  Any info or advice would be appreciated!

Comments

  • I'll just comment on the 650 question. I'm not a bike fitter, and know little about the use of all the numbers you generated from Retul fitting to determine the style of bike you should get, nor the charactaristics of different manufacturer's frames.

    Back in 2000, when I bought my tri bike from QR, molded carbon fiber frames were exotic to the point of invisible. Bikes were all made of round tube metal. The only way to get one's position low enough was to have a very short head tube. Even then, for shorter people (< about 5'9"), only using smaller wheels would allow a big enough drop from saddle height to elbow pad height. Aerobars were also a problem, raising the effective height of the arms too much.

    Now, with the advancement of carbon fiber technology, radical integration of stems and head tubes, and aerobars with intergrated elbow rests flush with the bar, it is possible for many shorter folks to achieve a proper position with a 700 c frame. And that's the key question to ask - will this bike allow me to achieve a proper aero position, with proper joint (shoulder, elbow, hip, back) angles?

    If you are a "size 48" it is probably still way easier to get that proper fit with a 650 bike. Having said that, you have to weigh the downsides: hard to get tubes, tires, wheels, forks (if yours breaks, like mine did). Can't switch wheels between bikes if you have a PowerTap hub and want to use it on your 700c road bike. Etc. Bottom line for me: if you can really find a 700c bike that fits, go for it, but you may get the best results from a smaller frame if you want to ride in an aggressive aero position.

  • I'll echo Al's comments as a fellow 650 rider. If you can find a bike with 700s that fits, go for it. You have lots more options for tires, tubes, support from other riders, and on top of that getting the tires on/off isn't as challenging.
  • Feel free to send that off to Todd at TTbikefit.com for his input too!
  •  Melissa,

    Felts are long and low bikes.  They are "generally" better suited for folks that are more torso than legs.  Some bikes are tall & narrow, some are long & low and others fall somewhere in between.  Felt certainly chose a side which to be on.  I don't pretend to have the expertise to interpret your measurements to give you a definitive answer.  Is your fitter saying it fits you because it really fits or because he wants to sell you a $12,500 bike (or the $5,000 frame)?

  • Having owned a 650 setup in the past, i agree with everyone here. go 700 if you can.
  • Thanks everyone for your input. I will send the info to TTbikefit and see what they say.

    The whole long and low thing is what had me concerned, since he said that cervelo wouldn't really work without a lot of spacers which would make it less aerodynamic. But I thought cervelo and felt were both long and low, but my knowledge on this is extremely limited.

    Al, thanks for your knowledge on this. I guess your point about achieving the most aerodynamic position is sort of where I'm at. If 650 really is the best bet to attain that eventually then that's where I want to put my money.

    Bob, I'm not too worried about him trying to make a sale. He really isn't a dealer, he specializes in fits. The only bike he totally steered me away from was Trek, which I could tell he had his own bias about...but I wasn't that interested in a trek anyway. That said, he has relationships with the major brands and could get me a little bit of a discount on the big names, so I don't think he has an extremely vested interest in what I get put on. I'm obviously not obligated to buy from him, and we were both up front with that.

    If any other fit experts have any opinion on this, it would be appreciated.
  • Cervelos are also long and low from my understanding. I would think if the Cervelo wouldn't fit well the Felt wouldn't fit all that well either. I currently (for the next couple of weeks anyway) have a Felt B2 (which is basically the same frame as the previous DA). I should be on a tall & narrow but I didn't know squat about fit when I bought it in '09. The Felt is just the wrong bike for me and I can't get a real good fit because I'm too stretched out on it. Trek Speed Concept 9.9 should arrive in early-April.

    Getting a second opinion from TTBikeFit should squelch the speculation.
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