Need help identifying what size bike I have bought

[insurin]

I have just bought a Trek 7.2 FX second had. I was informed it was a large. When I got the bike I was looking for a sticker of some sort that tells you the size. For example Specialized has 54cm/56cm etc on the downtube. This bike has nothing to indicate the size.
I am using the official website to manually measure but I am getting conflicting measurements. I must be measuring from the wrong start point or end point.

I am using this site

http://www.trekbikes.com/uk/en/bike...rl=uk/en/bikes/town/recreation/fx/7_2_fx_disc

I can measure the head tube length (C on the chart). This is 16cm which indicates it's a 20 inch frame.
If I measure standover (L on the chart), I get 78cm which is a 20 inch frame.
If I measure effective top tube (E on the chart) from the front of the seatpost to the centre of the head tube I get 54cm indicating it's a 17.5 inch.

I am 6 foot. 33 inch inside leg and have been riding a 56cm Specialized Tricross Sport for the last 4 years.

Any pointers?

 

[steveindenmark]

Have you looked under the bottom bracket?

Steve

 

[insurin]

Nothing on the sticker apart from a serial number

 

[insurin]

I think the writing says tbl-2277

 

[Stu Plows]

I thought the measurement was down to top of seat tube to the centre of crank?

 

[Dusty Bin]

Not sure why you'd want to look under the BB. Does the bike fit you?

 

[vickster]

I think Trek hybrid frames are measured in inches, something like 15, 17.5, 20, 22.5 or similar

http://www.trekbikes.com/us/en/bike...sizing?url=us/en/bikes/town/fitness/fx/7_2_fx

I guess the 20" or 22.5 would be a large?

 

[Stu Plows]

Here you go - http://www.trekbikes.com/faq/questions.php?questionid=49

 

[insurin]

Here you go - http://www.trekbikes.com/faq/questions.php?questionid=49

Thanks. Its 20 inches. Now I need to sell it. It just does not feel right