Hey guys,

I am hoping for some advice on comparing a few different bikes. Am I right in saying that I should ignore top tube length as when looked at without considering seat tube angle mis dimension can be misleading. To get a more practical idea of what my position will be I should be comparing stack & reach therefore?

The bike I am considering is a 2015 Specialized S-Works Tarmac in either a 56cm or 58cm (note I am 187cm tall, 79kg, 78.3cm bb venter-saddle top), flexible, have put in 7000km so far this year).

Currently I have 2 bikes & happy with fit on both:

Scott CR1SL (2012) 58cm
Stack 603mm (no spacers under stem & could comfortably drop 1-2cm further tomorrow).
Reach 394mm + 110mm stem= 504mm

Canyon Inflite AL (2014) 58cm
Stack 590mm (ride with 25mm of spacers as that is how the bike came set up & it’s my winter bike)
Reach 388mm + 120mm stem= 508mm

& now it is between the 2 sizes of Tarmac I need help with:

Specialized S-Works Tarmac (2015) 56cm
Stack 564mm
Reach 395mm + 110mm stem= 505mm

58cm
Stack 591mm
Reach 402 + 100mm stem= 502mm

So, when you look at it I could ride the 58cm with the stem slammed & a 100m stem (is that so short as to muck up the handling)
or
Ride the 56cm but with probably 2cm of spacers under the stem.

Thoughts?

Cheers!!

pete

Road geo is in the dark ages. The same factors that effect handling on mountain bikes also apply to road bikes. I would go with the longest wheelbase you can get away with that you can make comfortable.

Road geo is in the dark ages. The same factors that effect handling on mountain bikes also apply to road bikes. I would go with the longest wheelbase you can get away with that you can make comfortable.

Spoken like a true MTB’er JCL 🙂
Surely if you know your ideal effective top tube length and when the head tube is too tall (like your Scott ) you should be able to size your bike properly just by looking at a geo chart. You are running short stems for your height and IMHO bikes handle better with longer stems and the weight further over the front wheel (there’s a reason the pros have 130-140 stems) and I have to disagree with JCL

Now anecdotal sizing evince on forums is meaningless but for somebody the same height as me I’m surprised you are on 100mm/110 stems, fair enough if you prefer a sit up and beg style of riding but it really sounds like you are riding the wrong size bikes and could do with a bike fit.

I can see why people like stack/reach and appreciate how most manufacturers sizes are not linear especially when they reach the extremes but if you know your ETT+ideal stem it’s easy to see how any small seat angle changes or head tube lengths can alter cockpit length.

You seem quite serious so I’d say get a bike fit! Then forshaw you will know

I’d say get a bike fit!

So would I. Any decent bike shop selling that sort of frame/bike will include a full fit as a part of the sale.

The reason pros have such long stems is they want the lightest, smallest, (oh and aero) frame possible. If you want high speed descending stability? You want wheelbase.

I also bet half the out of the saddle sprinters who go over the front and stove their heads into the deck wouldn’t if they were running 80mm rather than 120mm stems.

My Scott has a 110mm stem & the Canyon has a 120mm stem.

I began cycling 18 months ago & bought the Scott to compete in etape du tour last year. I placed in the bottom 20% last year however this year improved to top 15%, 4 w/kg (330w) FTP & dropped 19kg to 79kg.

I can ride in the drops for hours on the Scott so have no fear of a more aggressive set up. I love cycling & want to race next year & as much as I love the Scott it’s more an endurance frame & I think I can go faster with a more aggressive position.

With the Specialized I’ll go to a concept store for a proper fit.

With the Specialized I’ll go to a concept store for a proper fit.

Not entirely necessary. Any GOOD Spesh dealer will offer that as well. Whereabouts are you?

I’m in Geneva. I’ll most likely pick it up next time in London hence why I would be more likely
to visit a concept store.

What are you on about JCL ?

If a pro goes over the bars its because there is a clash of wheels or a pile up and stem length will make bollok all difference, also an 80mm stem on a road bike is a poor handling experience

Anyway, my vote is go to a shop and pay for a fit ( go to cadence sport and get Adrian timins to fit) so you know that the fit isn’t based on a brand or assumption to buy
When you are contemplating a big bike purchase then 100 is relatively small

also an 80mm stem on a road bike is a poor handling experience

In what way?

In what way?

http://cyclingtips.com.au/2011/02/the-geometry-of-bike-handling/

from http://www.velofitter.com/blog/2010/6/21/how-to-choose-the-correct-size-of-road-bike.html
http://cyclingtips.com.au/2011/02/the-geometry-of-bike-handling/
“trying to fix an ill fitting frame that’s horizontally too long or too short by using a long or short stem, or by moving the saddle too far fore or aft, can compromise the handling characteristics. What do I mean by “handling characteristics?” Well, the bike can feel like it’s fighting you when cornering, or may not want to track straight when you’re your climbing out of the saddle, or can feel like it’s too responsive (i.e. “twitchy”), or can shimmy when descending. As a rule of thumb for general purpose road riding, a longer and lower position, provided it’s comfortable, is preferable to one that is high and short; that’s going to be hard to accomplish if the top tube is too long for you”

A lot of sense in that first link. Especially the BB drop and rear centre length comments. The thing is, “People started identifying this small rear triangle as a “race bike”, and therefore a race bike must handle better” this applies to front centre at least as much as rear centre.

That second link is a load of traditional guff that’s just recycling the same old crap. You’re smarter than that Gary. I mean, who has ridden a road bike that was too stable? Most that I’ve ridden feel like you can only brake hard with the thing stood up or the front wheel wants to tuck.

I saw a guy about 5’10” at the LBS last week who had a bit longer torso ratio and ended up with a 52 Roubaix with at least a 120mm stem and toe overlap! Utter crap.

I would say you are smarter than that too. I think of it as like the differnces between moto and moto-gp, you can’t apply dirt sensibilities to Tarmac! Yes maybe the notion of a short steep ‘crit’ bike isn’t relevant any more? (I’ll leave that up to those that actually race them). It’s all about the weight over the front wheel and how far forward the hands are relative to the front contact patch.
All those new nodder riders with their short stems pointing to the sky who only ever use the tops who complain of ‘nervous cornering’? Nothing to do with ‘these twitchy road bikes’ and not solved with a shorter stem to slow the steering down it’s solved by getting the CoG forward/longer/lower and pinning it.

Re anecdotal LBS sizing, I have had a couple of fits the last by nasty Nick Frendo (remember him) when he was BG qualified and over a few years have settled on a 565 top tube with 130 stem and classic 73°/73° 172.5 cranks and can’t go over 16cm HT (which discounts most sportive bikes) so most frames are 56’s for somebody 6ft1 you might think that’s way too small but the bikes fit like a glove, corner and are stable at any speed, plus I use the drops a lot not just the hoods. Bike geometry/fitting is not an exact science and is always an interpretation so we will have to agree to differ 🙂
So as to not fully hijack the op’s thread I would wager the specialized would handle better than the canyon just by looking at the geo chart, me personally would have struck it off the list without swinging a leg over one, I would say get a fit done beforehand and then apply that to the frames/bikes you look at, it sounds like you are quite flexible and manufacturers head tubes have got very tall recently

Thanks guys. The cycling tips article is great–I will read & get into that in some detail.

The Scott I bought because it was a good discount & I didn’t know jack about bike riding. The Canyon Inflite AL I also own is only for winter training–so I don’t mind the position or way it handles as I am never racing it. That bike is all about getting out for 4-5 hr training rides mostly in z2-3.

I have goals this winter to get my FTP north of 350w by the start of next season & race for the first time–going by the tables I would be cat 3, approaching cat 2.

So I want to get the right bike & build it up exactly in the spec I want.

going by the tables I would be cat 3, approaching cat 2.

As I’m sure you’re aware they don’t really count for anything!

I’m not aware actually. I’ve never raced (sportives are only thing close). I know my power curve but granted have little understanding of the racing tactics needed to deliver economy of effort.

Join a club, learn to ride in a group before pinning a number on, don’t be a squirrel or a chopper 😉

Tables may give you an idea in a TT, but there’s so much more to road racing than your power output.

If you are coming to London then I would head down to sigmasport in Hampton Wick, 30 mins by train from Waterloo. They are a serious road outfit and do Specialized. The owners also hold the franchise for the Kingston concept store, but I would head to the main store in Hampton Wick.

If you have the money buy a new bike but I wouldn’t expect too much improvement in results from what you have already. Best advice on this thread is join a club.

80mm stem = poor handling.

Depends on what bike really, i have an 80mm stem on a 44cm frame & its been fine, although I’m thinking of moving up to a 90mm version as my flexibility has improved.

I’ve got an S Works (54cm) running a 100mm stem and the handling is spot on for me. The best thing I ever did was get a bike fit which gave me a set of figures to work to.

I have ridden on club rides before so am not completely green. I do ride with some fairly handy riders out here in Geneva.

Think I will try Sigmasport & get the full fitting service. Perhaps I can fit on a 56cm–I did Muay Thai for several years so my flexibility is still good.

Hoping I can continue to improve my performance as I have been riding for just18 months & had a few bouts of illness even that time. Over that period I have lost 20kg & have gone from a bottom 20% placing in etape du tour last year to top 15% this year.