Determine Size of Specialized Roubaix

[gminator]

Im looking at buying a Specialzied Roubaix, the seller is unsure about the size.

 

Whats the best way to acturatly determine the size, I didnt see any markings on the bike that shows size?

[Tankman]

Measuring Tape in cm.

 

Top Tube is the important one

[gminator]

Ok cool thanks, In need a 52 cm.

 

So do I messure the length of the top tube parrallel to the ground, sort of like reach ( between the headset and the seat post).

 

Or do I just go messure the actual tube along with its slant if that makes any sense at all?

[Jakkals.]

Spez seattube measure = 52cm, top tube 53.5cm

Spez seattube measure = 50cm, top tube 52cm.

 

Make sure before you buy, My Tarmac is one size to beeeeg because the bike shop didnt take into consideration that the toptube was sloping.

[Let's Ride]

"So do I messure the length of the top tube parrallel to the ground, sort of like reach ( between the headset and the seat post)."

 

Correct, use a spirit level.

[AdrianDJ]

Do you have your ergo fit measurements? or similar? the effective tt length is the important one. straight line (parallel to the ground) from top of head tube (centre) to centre of seat post. can play around with stem length a bit but wouldnt want to go to short on a road bike..

[gminator]

"So do I messure the length of the top tube parrallel to the ground, sort of like reach ( between the headset and the seat post)."

 

Correct, use a spirit level.

 

Ok cool thanks for all the help.

 

But just to be super clear the distance accross the top tube (from headset to the seat post) parrallel to the ground (reach) should be 52cm.

 

I've got my hands on spirit level so Im going to go make some mesurements tonight hopefully buy the bike if all goes well.

 

I took the bike for a ride and it felt ok, but not sure what I should be looking for. I've only ever ridden moutnain bikes so the feel of road bike is completely new to me.

[gminator]

Also if the bike turns out be smaller than expected (which is very likely), being 1.68m tall will I be fine with 48/51/52ish frame?