650 c wheels- what is the tradeoff?

[wiseowl]

So it looks like I am right on the borderline between Giant XS and XXS. The XS is on 700 cc wheels, and the XXS is on 650 cc wheels. I am marginally more sized (5 feet tall and 27.5 inseam) for an XXS, it appears, but could go either way. The XXS may be a better $ deal- I can get a better rig for my buck. Any of you riding, or considered riding, the smaller wheel? What is the tradeoff?

[mimitabby]

the biggest tradeoff I know is that there are few makers, no colors, and no one else has them.

[Tri Girl]

To me- I don't see any tradeoff. I ride on 650's and I LOVE them. Plenty of people around here ride 650's (and oh the race tires I'm eyeing on eBay... don't even get me started.) I don't have as many color options should I choose colored tires (which is not an issue for me), and I guess I don't have as many tire options- but again-not a big deal. I've never had a problem finding tires or tubes (but if I flat out on the road and need a new tube and don't have one- then I'm SOL- but that's why I carry everything I need).

For me, I like the quicker power when accelerating. Let me explain that- I can "get up and go" much quicker on my 650's on the Cervelo than I can on my 700's on the Giant. I can outsprint DH from a dead stop on my "teeny tires" (as he calls them). They have much more "giddy up" than my 700's (at least IMO). I know it all evens out in the wash, because with smaller tires you're technically putting in more pedal strokes (because the tire rotation is quicker), but I really don't think it makes a diff.

And plus, the 650's are more aesthetically pleasing to me. On a 48" frame, they look far more proportional than the 700's. I always feel like my Giant bike is just that- a tiny frame (it's an XS) with GIANT wheels.
It looks silly to me. The smaller tires don't make me look like a kid riding on my dad's bike.

[Eden]

I think it has more to do with fit than wheel size. I have both a 700c bike and a 650c bike and I find the opposite of TG to be true for me. Both are racing frames, one is Carbon one is Ti. My 700c wheel bike, for me, is MUCH quicker to accelerate and a much better climber. I am short, with more leg than torso though, so the 700c bike just fits me better.
I'd say really fit each of the bikes comprehensively and figure out which one really is the best fit for you and don't worry about the wheel size. The only big disadvantage to 650's is if you race you'll never be able to get neutral wheels. If you don't race, don't worry about it. If you do race, just be prepared to always put in your own wheels.

[smilingcat]

there are several pros with 650C wheel on a smaller frame. frame geometry doesn't have to be compromised to get the wheel to fit. biggest problem I've seen is very short head tube length. Shorter it is, the more wear and tear on the head set not to mention mor finicky in adjustment.

As tri-girl says, 650C wheel definitly has advantages over 700C wheel in accleration. You can "spool up" much faster on 650C. It takes lot more energy to spin up the 700c then it is with 650C (its physics of things and unless you are god there ain't much you can do about that). Faster spin up means faster acceleration. The whole thing revolves around a thing called angular momentum.

My old Ti bike had a 650C wheel and it was comfortable.

cons: choices of wheels are limited and less manufacturers are building 650C wheels. less choice in tires too. I wanted velomax orion?/circuit? or asscent wheels but they only came in 700C (I think velomax is part of easton now). I just checked yes velomax is now part of easton hmmm they now have 650C asscent/orion/circuit.

If you race see eden's comment. also at UCI sanctioned race, 650C wheels are not allowed for TT's (atleast that is what I remember).

Go with what is comfortable. They are still enough choices for 650C wheels.
And I think Tri people still prefer the 650C wheels so it wont be discontinued any time soon.

smilingcat

[Eden]

If you race see eden's comment. also at UCI sanctioned race, 650C wheels are not allowed for TT's (atleast that is what I remember).

As long as *both* wheels are 650 it's OK (at least it is for USACycling - better be cause my TT bike has 650's - and I don't think the rules vary too much from UCI). You can't have an odd wheeled bike - think getting ultra aero, by having a smaller wheel on the front than on the back.

[wiseowl]

I should specify that I do not race, nor do I ever plan to...but your comments are still very helpful and I am sure there are others in my boat who do race. Glad to hear the "extra" pedalling doesn't seem to hurt much- my DH is a stronger biker than me so we are always trying to find ways to eqalize us for rides together, and I am concerned the 650s would be one more notch against me. Out of curiosity, how tall are those of you on 650cc?