Confused over frame sizing

[Typhon]

I'm looking to upgrade from my Triban which is a 60 cm but that is not the seat tube measurement - it actually has a 53.5 cm seat tube. It also has a 56.5 cm horizontal top tube (not the effective top tube, the actual straight line). I've been measured a couple of times by medical professionals at 6'2" and I have a long body and relatively short legs (I wear trousers with a 31" inside leg).

So everything I've read on the internet would tell me that the bike is a tiny bit on the small size for me - except it's not. I feel stretched and always have done. I've replaced the 110mm stem with a 90mm one and I still feel very slightly stretched and get pain in my right shoulder on long rides.

Now I'm thinking of upgrading I'm looking at frame geometry more and more as I will almost certainly buy online and I've read that the top tube measurement is the most important. On the basis that 56.5 cm is too big by at least 1cm even after reducing the stem 2cm, I was thinking that a 53 or 54 cm top tube would be correct. However given the bikes I've looked at this puts me in the "medium" range with a 54 or 56cm frame as measured against the seat tube. Surely this is too small for me?

I've even come to doubt my own height! I have even measured myself and late in the evening I am 73.5 inches i.e. 6'1 1/2 so why I am so stretched out on a frame and stem that would everything online would suggest is suited to someone who's about 5'7 - 5'10?

What am I doing wrong - or sometimes do people just have a need for a slightly smaller frame than their proportions suggest, or even have a preference for something slightly smaller?

 

[mark st1]

Think you need to visit a good local lbs and get a proper bike fit mate. All manufacturers seem to be different even though they all seem to go with the s,m,l.xl etc the sizes can be vastly different.

 

[Typhon]

Yeah the lbs option would ensure I get a perfectly fitting bike I suppose. It just irks me having to pay 2 or 3 grand for a carbon bike with ultegra when you could get one for £1300 online. I guess it's no different to other shops, a 50% mark-up is pretty common I hear. At least with something like this you are actually getting advice whereas with say an ipad the store pays £200 for the item, sticks it on a shelf and you give them £400 for it.

 

[vickster]

I don't think stores make anything like that mark up on an Apple product...anyhoo

There are some good deals out there in stores on 2012 bikes - some brands are online only, many aren't ... you may need to travel a bit though, you are in the middle of the country though which can't be a bad thing

 

[Typhon]

A friend of mine is doing a thesis on Apple's business strategy and told me the other day the mark-up was 50%. A quick google shows that is Apple's own mark-up though, not the stores. Guess I wasn't listening properly. That would be their mark-up if you bought direct from them though.

I guess no-where is a million miles away but then again, as there's not much between Bristol and Birmingham, everything is 50 miles away!

 

[vickster]

Hop on a train and have a day in the big smoke

 

[Typhon]

Could do, I'll have to see if anything else catches my eye. That Ridley was very tempting!

 

[vickster]

I wouldn't leave it too long, limited offer I'd say

Pearsons own bikes are pretty nice too

 

[simon.r]

The more I think about this the less important I think it is, given the relatively large adjustments you can make with seat-post and stem length / angle.

See my post on this thread for examples.

 

[Typhon]

I wouldn't leave it too long, limited offer I'd say

Pearsons own bikes are pretty nice too

I'll take your word for that.

The more I think about this the less important I think it is, given the relatively large adjustments you can make with seat-post and stem length / angle.

See my post on this thread for examples.

Yeah I don't think seat post length is important as the saddle can just go up and down to compensate. Mine is only a 53.5cm and the saddle could go up way more. In theory you could make large adjustments with the stem but too much and I think you'd effect the steering. Just changing mine for one 2cm smaller had a negative effect on the steering for me, it feels more twitchy now. So I'd like to have a good base in terms of top tube so that I don't have to adjust too much.

 

[jim55]

yeah the top tube length is the most important ,but your present bike has a virtual tt length of 60 cm ,which is too big by the sound of it ,id try a 58 or even a 54 but rem with the smaller frame the stem would need to b longer to compensate ,personally id pay for a good bike fit and buy a bike to suit yr dimensions ,a lot of companies will do a bike fit without a view to buying a certain bike off them as part of the deal ,seperate companies

 

[Typhon]

I did try the 57cm model at the time in Decathlon and it was far too small. I was in there the other day for something else and tried the 57cm again and it was way too small, probably further out from my correct size than my 60cm now that I think about it. So I guess it is fine margins, although if you're even stretched by a couple of cm you really notice it on the long rides don't you? Wouldn't be an issue if I was just planning to pop to the shops on it but I have big plans in terms of mileage this year, especially this summer!

The bike fit is tempting. Specialized have a BG fit machine in their stores. I could get a Roubaix with the equipment I want and it'd fit perfectly and be so comfortable on the moon-like surface of the roads around here. There's just the small matter of £3000 and about £200 for fitting! I guess with an LBS they'd probably throw in a human fitting for free with a bike.

 

[deptfordmarmoset]

Have you tried flipping the stem? Just in case it's a matter of being too low rather than too stretched out.

 

[Typhon]

I haven't tried that - I'll give that a go tomorrow and see if it helps with my reach.

 

[simmi]

I'm 5ft 11.5" and also have short legs and a long body.
My frame size is 56cm and I know this to be right as I have had a bike fit.
I would be very surprised if you needed less than this and would thing a 58cm would be about right.
As well as stem length your saddle position fore and aft is also very adjustable.
Mine is back a bit which helps on the hills.