Road Bike Sizing

[tjdixon911]

I'm looking into the possibility of buying a cheap Road bike from ebay, how does sizing vary from mountain bikes? I'm about 6'1 and currently ride a 19.5" MTB. I'm currently looking at a 53.5cm bike, does this sound about right?

Thanks

Tom

[itsnotarace]

Define where the 53.5 measurement is from? Assuming it's the effective top tube measurement then that is way small for you unless your torso is freakishly short for your size

Get someone else to measure you and put your results into here:

http://www.competitivecyclist.com/za/CCY?PAGE=FIT_...

[tjdixon911]

itsnotarace said:

Define where the 53.5 measurement is from? Assuming it's the effective top tube measurement then that is way small for you unless your torso is freakishly short for your size

Get someone else to measure you and put your results into here:

http://www.competitivecyclist.com/za/CCY?PAGE=FIT_...

I'll have to find that out, I assumed it was the same measurement as the 19.5" on my MTB frame making it about 21" - the bike is listed as a Medium/Large Giant Rapid if that helps?

[itsnotarace]

From Giant's website that appears to be 53.5cm seatpost but it doesn't say whether it's centre to centre or centre to top. The top tube on the M/L is 56cm. Without seeing you and knowing your measurements I would say you'd really want the large over the medium/large

Can you get to a local Giant stockist and try a few?

[b2hbm]

tjdixon911 said:

I'm looking into the possibility of buying a cheap Road bike from ebay, how does sizing vary from mountain bikes? I'm about 6'1 and currently ride a 19.5" MTB. I'm currently looking at a 53.5cm bike, does this sound about right?

Thanks

Tom

Well if it's any use, I'm 5'8" and ride a 54cm frame so 53.5cm sounds a bit small for your height.

IMO it's not the seat tube (53.5cm) that's important, it's what they call the effective top tube length, which is basically a horizontal line from the center of the head tube (fork/steerer) to the center of the seat pin. I generally aim for anywhere between 54 & 56cm, so I'd guess you'd need at least 56cm ?

Brian

[Roman]

You will probably find you need a size 56cm for a bike with compact (sloping top tube) geometry or size 58-60cm for a bike with 'traditional' (horizontal top tube) geometry. Depends on the geometry of the frame & how it is measured though.

[Chicken Chaser]

I'm riding a Boardman 50cm and I'm 5'8". When on the hoods, I cant see the front hub as its covered by the bars. Seat is just about spot on (still moving it mm by mm) so I think it all depends on the geometry of the bike. Mine feels just right in length.

[PH5121]

I am 6ft 2 and like you have a 19.5 inch mtb.

I would go for the large frame if looking at something from the Giant range.I have a Giant Defy road bike, and I needed a Large rather than the Medium/Large.

Edited by PH5121 on Thursday 27th January 09:13

[tjdixon911]

I had a look and a ride of a couple of bikes at the weekend, the Giant suited me in the Large (55.5CM in the brochure) and a 58cm Cannondale which I thought wasn't too bad albeit slightly bigger. So been looking around the net and come across these;

http://www.rutlandcycling.com/26051/Viking-San-Mar...

http://www.rutlandcycling.com/30787/Viking-Torino-...

They look pretty good to me for the money but I have never heard of them, anyone know if they are any good?