Hi, I’m new to triathlons and I have yet to purchase a bike. I was looking online for the right size bike and I am not sure what size to get. Any suggestions?
that’s, uhm, kinda vague.
find a Local Bike Shop you like and trust, and that pays significant attention to triathlons. if you let people here know where you live they’ll have suggestions on which LBSs are good tri shops.
bikes are usually made in 2cm increments, since you said you were fairly tall - I’ll stick to bikes that may fit you.
most people around 6’ will fit in a 56 or 58cm bike - and yes, there are exceptions(more likely smaller frame than larger) - depending on how flexible you are and the fact that some bikes have longer/shorter top tubes (from the seat to the handlebars)
Figure 2cm larger or smaller frame for every 2 inches of height.
If you already know your road bike size, a tri-bike will either be the same or 1 size smaller (depending on frame)
…and before people start jumping on me (“I’m 6’6” and ride a 48cm!!!") this is a just a starting point.
Acronym,
Can I ask you why you chose a 48 cm bike? Also what type of bike are you riding? I’ve heard that Giant makes bikes that have undersized geometrys in comparison to normal bikes. We are about the same height. Im 6’5" and I have a 36" inseam. According to the standard formula my bike size should be a 61 or 62 cm.
I suspect he meant a 58cm bike. His elbows would hang over the pads on a 48. I’m 6’3"+ and ride a 58 (tri bike) w/a 90mm stem if thats any help. Everyone is different. I echo the advice to find a nearby shop you trust.
I suspect he meant a 58cm bike. His elbows would hang over the pads on a 48. I’m 6’3"+ and ride a 58 (tri bike) w/a 90mm stem if thats any help. Everyone is different. I echo the advice to find a nearby shop you trust.
Yeah you are probably right about that. 
I don’t ride a 48, I’m 6 even and ride a 58. My point (and why it is in quotes) is that undoubtedly someone will chime in and tell me that I’m wrong and not everyone 6’ will fit in a 56-58. This is, afterall, slowtwitch.
also, at 6’5" you will probably have trouble finding a bike that fits well (outside of a custom build). Trek’s seem to be sized a little larger. Maybe others can recommend frames that seem a bit tall or long for their size.
Thats good to know Acronym. I was looking into buying a Giant, but now I will check out Trek too. Thanks!
I’m 6’6" with a 38" inseam and I ride a 63cm road bike (Cannondale) and a 61 cm Cervelo P2K quite comfortably.
That Cervelo P2k sounds like a nice bike.
I like it and I haven’t really seen a reason to get a P3 yet. I have gone with an Oval adjustable stem to move the bars around a bit and i run it with HED bars but for the price it is a heck of a deal. I haven’t had any problems with aluminum being harsh and I’m in the 220 lb range. I did IMC last year on it. I’m looking for another 61cm P2 frame to set up as a pursuit bike.
IMC = Ironman Canada?
Yup. A good long ride but my bike treated me well. I run it with HED 3c wheels front and back or with a Renn disc in the back.
Wow, good to know. I’m not up to that distance yet but I’m aiming.
I wound up buying the Cervelo P2SL aluminum and boy am I happy with it. The 61cm fits me perfectly and in my first triathlon I averaged 21.7 mph without even doing muhc training. This bike rocks! Perfect for a tall person.
If you want steel, there is the Serotta CXII which they will custom build to your measurements. Mine is the most comfortable bike I’ve ever ridden (due to the custom build and a fine fitting at Fitwerx in VT). Even though it’s from a high-end manufacturer, it’s priced lower than many carbon bikes. If most of your height is from the waist up, you might try brands with a longer top tube, like Lemond. I ride one of their road bikes, but haven’t tried their tri bikes, because frankly I think their butt ugly.
As I’m sure others will tell you, don’t start with a particular bike in mind. Instead, start with a good bike fit, and then find a bike that suits your measurements.
I’m 6’4" with a 32 inch inseam. I ride a QR 61cm with a 110mm stem. Got my fit done by inside out sports. My bro is 6’9" with a 36 inch inseam. He rides a 63cm C’dale.
I am 6’5, 37 inseam. I got a fitted bike from Ves at Yaqui! Did not need to be custom. I sent in all my measurements,
and it fit me like a glove to a 59cm DE frame Tri bike. So, I would not guess since it is a lot of money to waste.
I thought I would need something larger based on what most write, but when I worked with Ves, this was not the case.
Best thing I ever did was go to an expert like Ves!!
Dave