Specialized bike geometry

[siadwell]

I've got my eye on a bargainacious Allez, but the only size available is 58cm.

I'm about 5'11" and according to Spesh's sizing charts, I should be looking at a 56cm. Obviously, I should really go in to the shop and get properly fitted, but I was wondering what differences there would be in practical terms between the two sizes. I have a bad neck and so am more interested in comfort than an agressive racing position.

 

[HLaB]

I've got my eye on a bargainacious Allez, but the only size available is 58cm.

I'm about 5'11" and according to Spesh's sizing charts, I should be looking at a 56cm. Obviously, I should really go in to the shop and get properly fitted, but I was wondering what differences there would be in practical terms between the two sizes. I have a bad neck and so am more interested in comfort than an agressive racing position.

I think you've answered your own question, especially seeing you have a bad neck.
However, I'm 5'9" in ride 54 and 55cm bikes; my Spesh Sirrus is an equivalent 54cm so you might get away with it with a shorter stem fitted perhaps but I'd try before you buy.

 

[Banjo]

The bigger frame will let you have less seatpost raised which may be better for a stiff neck but a taller frame also has a longer top tube which will have you stretching forward more .

You can move the seat forward a bit to compensate and fit a shorter stem but as HLab says you need to get a proper fitting.Dont buy it just beacause its cheap.If your not comfortable on it its no good.

 

[rockyraccoon]

I'm 6'1''. I've got the Allez size 58cm. I followed the sizing chart and it fits me perfectly.

The Allez 58 cm will be to big for you. Your bike needs to fit you properly in order to ride comfortably without hurting yourself. There are several threads in this forum about the consequences of inappropriate size/fitting such as uncomfortable rides; back, neck, hands, knees pain; and etc.

In your case, specially with your neck problem, you should definitely follow the sizing chart and get the recommended size. By getting the 56cm you only will have to do minor adjustments such as saddle height and position, and stem.

 

[accountantpete]

I think the only real difference is that the 58 will have a longer top tube - I don't know about your upper body measurements but with a 110mm stem this could mean that you have to stretch to reach the bars.

You could always get a shorter stem - but this might make the handling a little bit twitchy (if that is important to you).

 

[zizou]

Even if the Allez was the right size then it still has racey geometry so might not be the most comfortable option available.

 

[MacB]

I looked at their geometry, not sure which Allez, but I chose the triple and it shows:-

56 has effective TT of 565mm and HT length of 170mm
58 has effective TT of 582mm and HT length of 205mm
61 has effective TT of 600mm and HT length of 230mm

Due to the compact geometry I could ride any of these bikes as the standovers aren't that high, I'm 6'1", pretty standard proportionally(barring being a fat git) and have size 10 feet. Using Dave Moultons quick reference chart, which I find extremely accurate:-

http://www.prodigalchild.net/Bicycle6.htm

I know that my overall TT and stem need to be in the 700mm range, things like ST/HT angles do have an impact on this. I have 3 bikes two of which were converted to drops from flat bars, the effective TT's for each bike are 600, 596 and 576mm and respective HT lengths are 160, 200 & 167mm. Adding in stem length each bike is within 5mm of a 700mm combined TT/Stem total, angles account for the variance, and the ones with the shorter head tubes have a lot more spacers under the stem.

Though I could ride any of these the larger and smaller sizes would be putting me towards extremes of stem lengths and limiting my ability to tinker. I'd go for the 58 with a 120mm stem and expect to get a good balance of stability and responsiveness.

 

[PaulSecteur]

If I could point sir towards a Specialized Secteur, its an "endurance Road" bike. Meaning the geometry is more relaxed than a race bike, so should be easier on the bad back.

You really need to get on a bike you intend to buy, but going oversized with a bad back sounds like a recipe to having a bike with cobwebs on it because its painful to use.

A bargain isnt a bargain if it dont fit.

For reference, Im 5-11 with a 32 leg and a 56 secteur if perfect for me. A 58 might fit, but would be more of a stretch to the bars.

 

[MacB]

Another thing I find helpful is to envisage the front triangle, using effective top tube line, as pivoting around the bottom bracket. In this relationship the seat tube angle has the effect of deciding how much of the top tube will be fore and aft of a centre line through the BB. The steeper the seat tube angle the less top tube is behind the BB and vice versa. In real terms this means that if you had two frames of equal effective top tube, but differing seat tube angles, the one with the steeper angle would have a longer reach. This is working on the assumption that you would have identical saddle to BB relationships.

Some people would argue that they'd just alter the saddle position but I find my back and knees are fairly intolerant in this area.

 

[Norm]

I have a bad neck and so am more interested in comfort than an agressive racing position.

Then I wouldn't look at an Allez of any size.

The Secteur bars are an inch or so higher or go for a "tourer" like the Tricross, which is a couple of inches taller still.

 

[siadwell]

Thanks for the replies, guys.

Funnily enough, a Secteur was on my shortlist. There are some good prices to be had on 2010 models, so looks like that's the one for me. I'll get myself down to the bike shop after Christmas.

 

[ianrauk]

I'm 5'9" with an inseam of 31". I have Secteur Elite in a 56 frame. I tried the 54 which would have fitted but there was far too much seat post showing for my liking. I changed the stem from a 110mm to a 90mm for a closer reach.

 

[Norm]

I'm 5'9" with an inseam of 31". I have Secteur Elite in a 56" frame. I tried the 54" which would have fitted but there was far too much seat post showing for my liking. I changed the stem from a 110mm to a 90mm for a closer reach.

I'm 2" taller with an inseam about 2" shorter (yeah, picture that!) and my Secteur is a 54.

However, that's 54cm, I don't think I'd fit on a 54" frame.

 

[ChrisKH]

I'm 5' 11" and have got a 58 cm Allez and if truth be told it's marginally too big. Didn't have the option at the time but would go for a Secteur if I was doing it all again, or maybe a different make altogether with a tourer feel.

 

[e-rider]

You'll be fine on the 58cm especially if you have a bad neck

the only thing you might need to do is replace the handlebar stem for one that is 1 or 2cm shorter