I'm not actively shopping for my someday dream-tri bike, but I still enjoy looking at the new stuff as it comes out. I was a little dismayed (and possibly relieved that I probably won't be buying a 2015), because I've been hoping that my eventual bike will be able to have 700c wheels on both front and rear.
Felt, Cannondale, Cervelo, and lots of others all put 650c wheels on their XS frame size tri bikes, which unfortunately is my size. I'd been holding out figuring no biggie, the Specialized Shiv and Trek Speed Concept both have 700c wheels on their XS's, and my bike fitter has been encouraging me in either of those two directions.
But I just perused the 2015 Speed Concepts and this year they have 650c wheels on their XS frames too! There probably is SOME company out there besides Specialized who is finding a way to use 700c wheels on tri bikes at my size, but I don't know who!
Anyway, totally possible that things will change before I buy, just curious what peoples' thoughts are on the value of 700c vs. 650c? I hear arguments both ways; you're more aero with 650c, you lose ground with 650c due to wheel diameter, etc.
I don't want to be the girl with the weird size wheel when I need spare tube someday!
My specialized transition is XS with 700s. You may recall the problems I've had with my wheels and the basically-zero clearance between my tire and caliper. Part of that has to do with the size tire that is on there, but I do wonder if there's any connection between the geometry that specialized uses that few others seem to do (in re to 700 vs 650 on XS frames).
I admittedly don't know a ton about bike geometry and advanced mechanics, but I do know that when I was looking to do a TT with 650s, I got a lot of backlash (here actually), and I wish I had have gone with it after all. My bike (and the 2 other XS transitions that I know of) has a lot of problems, and I hate it. I guess you can't always know that before you ride it for awhile.
I would take carrying extra tubes to dealing with the mechanicals that I have in the last year.
With smaller wheelsize, you will almost always have to pedal with a higher cadence to keep your speed the same as someone on a 700c wheel. For some people it's not a problem. You also go a shorter distance with each pedal revolution.
Have you looked at Blue? I ride one of their older TT Bikes (XS) with 700c wheels and don't have any tire or pedal clearance issues. www.rideblue.com/
My tri bike has 650c wheels (also extra small). My biggest problem is that bike stores never seem to have spare tubes for that size in stock. So, I don't have an performance issues.
With smaller wheelsize, you will almost always have to pedal with a higher cadence to keep your speed the same as someone on a 700c wheel. For some people it's not a problem. You also go a shorter distance with each pedal revolution.
Have you looked at Blue? I ride one of their older TT Bikes (XS) with 700c wheels and don't have any tire or pedal clearance issues. www.rideblue.com/
Nope, never seen a Blue bike! I can look into that.
The P2 looks like it has 650c at 48cm, like so many others. That would probably be my size. I'm like 47/48cm in road bikes.
Most of my friends ride 51 and 54 cm bikes, so this is a foreign consideration for them. Generally 51cm and up is 700c across the board.
Obviously if 650c is what gets me the best fit, it's probably the best choice. But if someone has a geometry tweak that allows 700c to work about as well, I'd sure prefer that! No plans to sell my road bike, and would prefer for wheels, spare tubes, tires, etc., etc. to be interchangeable.
Oh I see, I was looking at the Classic P2 geometry measurements which was 650c in 48cm. The roller on my mouse is too quick, went right by the first table!
Fuji norcom comes in a 49 with a TT of 49.5 cm and runs 700s.
The cervelo P5 has a TT of 49.7cm in their 45cm bike (I'm assuming thats the xs) and they run 650s.
What Miranda Carfrae ride? Because doesn't she ride 700s despite being like the size of a pixy?
I'm pretty sure she is on 650s.
The most recent article I can find is about her 2012 Kona bike, when she switched from cannondale to felt, and determined 650 allowed a better fit, ie more power, which is arguably more important than the highly disputed "physics"
Eta: I say "physics" in quotes, only because I think there is probably good scientific info out there, but all I've been able to find are opinions that differ and aren't really citing actual science. Is there a physicist in the house?
Post by katinthehat on Aug 29, 2014 16:11:37 GMT -5
For sure, the best bike is one that fits you the best allowing you to get the most power out of it. Aero position doesn't mean anything if you can't hold it for very long or your lady bits hurt so much you can't pedal effectively, etc.
Fuji norcom comes in a 49 with a TT of 49.5 cm and runs 700s.
The cervelo P5 has a TT of 49.7cm in their 45cm bike (I'm assuming thats the xs) and they run 650s.
What Miranda Carfrae ride? Because doesn't she ride 700s despite being like the size of a pixy?
My road bike effective TT length is 50.6 cm. I'm not sure what the outer bounds are on the range that would fit me.
It looks like Miranda Carfrae does ride 650c's now. Interesting! I guess it makes sense that adjusting the gearing can address some of the downsides of 650c.
Post by reginaphalange72 on Aug 29, 2014 17:43:45 GMT -5
Rinny does ride 650s. She talked about this at the Q&A thing before Boulder. Apparently she constantly has people asking her if they can buy her old bikes.
My Quintana Roo (CD0.1) is a 48 cm and has 700s. That could be another option as well.