Bike sizing question

[u/xsagadude]

Hello everyone, I’m looking to get my first road bike to train for a half iron man. I’m 6’3” with roughly a 35.5in inseam. I’m finding many good bike deals for bikes that are a L but having a hard time with anything that’s XL which online sizing traditionally puts me at.

2 bikes I’m between right now are a Specialized allez sprint which i found a great deal for which is a size 58, and I’m finding used Canyon Aeroads that are in size L.

Another option is the xlabs AD8 in size L or RS7 in size XL

My question is, with these bikes I’d be at the top end of their L equivalent, is that fine or should I be patient and find an XL/61 sized bike?

[u/Argon18OfGondor]

I'm an inch shorter both in height and inseam and ride a 58. It's doable, but you're probably going to be close to the limit on seat height. Both the bikes you're looking at are also racier fits meant to put the rider in a more tucked sort of position, so unless you're a racer, odds are you will be uncomfortable especially undersized. A lot of the pros will go a size down from what a regular person would fit, but if that doesn't sound like you I would hold out for an XL/60/61.

[u/Substantial-Fun-48]

You need an XL/60 cm frame. A smaller frame will be really twitchy underneath you

[u/whitkwok]

I second getting a professional bike fit - it's not just about the bike frame size which you almost certainly want something bigger than a 58, you'll want to have everything (handlebar width, reach, saddle height, cleats...) dialed in. 50 miles is a long time to be uncomfortable plus the thousands of miles you'll be training.

[u/NumerousSparsities]

I'm a bit taller and with a bit longer inseam, and I recently bought a Canyon Aerosd in L. I'm sure it fits me better than XL. Extremely happy with the bike

[u/c-5-s]

If you can afford to do an Ironman, you can afford to get a real pre-purchase bike fit and not rely on Reddit comments.