My T3 63cm frame seems small

[staff1975]

My new T3 in a 63cm frame has just arrived today and it looks great. Already done 25 mile on it this afternoon and my backside is sore and my legs feel like jelly.
My problem is it seems small as I am 6 ft 5". I had to take it into my local bike shop coz my nearest Decathlon is 150 mile away coz the gears 4-8 were clicking and doing my head in.... but that's another story. The guy in the shop said that bike is too small for me and I replied its a 63cm frame. He said there's no that's a 63cm so he measured it from the crank to seat post bracket and it measures 57cm? He did explain that some manufacturers measure it as if the top tube is parallel but he said even if they do its still only a 60cm at best.
I rang Stockport, Decathlon where I bought it from and the guy said to measure it from crank to seat tube which I did and it was 57cm. He didn't believe me coz he boxed and sent me the bike. He put me onto one of the tech guy on the phone who basically said the last bloke was wrong. He said to just look for the red sticker on the seat tube with a number on and surely enough it said 63cm. He explained it is impossible to measure a compact framed bike which most modern bike are now a days.
I'm still not convinced and neither is my local shop. Could they have made an error when marking the frame with the size??
Could anyone else with a 63cm frame please measure theirs from centre of crank to centre of seat post and tell me what it measures ?

 

[AndyPeace]

I would ask Decathlon for the full Geometry specs for your tribian. It's not impossible to measure a compact frame but Larger sized compact framed bikes don't always have an effective top tube length that tally's with the actual frame size. (If I had bough my bike in a 62cm size, the effective top tube length (parallel to the ground from the center of head set to where it crosses the seatpost) would have been just shy of 60cm.) Larger frames have different geometry, like taller headtubes and different angles
This won't tally with your bike but I thought I'd add it as geometry specs will show how larger sized bikes measure up.
If it is the right size, you may need to make a few adjustments to your bikes set up, to get it to fit you, like a longer stem. sizing issues like this is why you should buy a bike from a local shop and take a test ride, or at least sit on the bike to try it for size. It's so much easier to resolve/clarify things when your face to face.

 

[staff1975]

Trouble is I really wanted a Triban 3 because I asked for advice on here for what bike to buy for my £300 budget and the T3 was the most popular suggestion by a long way and my closest Decathlon store is over 150 mile away so had to buy online

 

[sreten]

Hi,

The nominal size in terms of seattube length is where a level top tube would
intersect with an extended seatube, it is not the actual seatube length.

Is your seat height set correctly ? Heel on pedal your legs should lock out.
Have you tried dropping the bars and adjusting the seat fore and aft a bit ?
Dropping the bars and setting the angle can make big differences.

I think your LBS guy is probably wrong. According to Decathalon 63cm
suits 6' 3.5" and that is near enough for proper seat height and well set
up bars to make up any difference unless you have unusual proportions.

A very basic indication is standover clearance in the middle of the toptube.
About 1" the bike should be a good fit for you. Over 2" its likely too small.

rgds, sreten.

Sloping top tubes not only allow lower standover near the seat, they
also allow longer (and stiffer for forks) fronttubes. So standover is
best judged in the middle of the toptube. My bike is pretty near
perfect for a sloping toptube. Some but minimal clearance stood
with the stem in my crutch, about 1" midway along the toptube.

FWIW for real road bikers : the stem should never point up,
it should be flipped to point down, and you must have at
least one of the height adjustment rings above the stem

Stem up and no top rings in the image above indicates its
the same as delivered and unlikely to be the best setting.

To be really pedantic because of the bottom clamp the
headset doesn't need the rings at all except for setting
the preload via the top for the bottom clamp.

 

[staff1975]

I know you do not measure the actual top tube but the virtual top tube. But mine still measures 60cm and it a 63 bike. I have just rang Warrington Decathlon as they have a 63 in stock to measure. He confirmed the seat tube is 57cm and the virtual top tube is 59cm ?? He said the 63cm measurement comes from the crank to the headset. So that's the 3rd different way a Decathlon staff member has told me to measure the frame

 

[AndyRM]

It might be worth taking some pictures of you with the bike so that you can get advice based on how it measures up in comparison.

 

[vickster]

There's some really tall bloke in Kent (jifdave?) who has a triban 3 - he has a longer seatpost I think, maybe a stem change

Tribans do seem to have a smaller geometry than other manufacturers

 

[staff1975]

Had this email back from Decathlon today.

Hi John,
The Triban 3 which you purchased is a road bike which comes with a compact frame. When measuring frames sizes for any compact sport bike it is standard practice of the bicycle industry to work off effective measurements, rather than actual measurement from the middle of the bottom bracket to the top of the seat tube.
What we have done in store is take a picture of how to measure a compact frame, the image is attached, it is measure from arrow to arrow. Also I have found a diargram of how to measure it, again the image is attached, the correct measure is length B.
Thanks,
Emily

Sorry not sure how to cut and paste the photo's but basically it shows that you measure from the crank upto where the virtual top tube would meet the seat post. Thats where they take the frames measements from.

I'm happy with the bike anyway coz ive hightened the seat and may get another stem in future but just going to see how it goes for now.

All I need now is a bit decent weather!!!