currently on the lookout for some Specialized Shiv frameset for next tri season.
Just got re-fit for my tri position, resulting in a slightly more aggressive position. Feels fast but nice and comfortable still. Think it will save me some watts thanks to more aero position.
My key fit coordinates are the following (I am 1,80m tall):
First of all a disclaimer, don’t take my advice too seriously, I am not a qualified fitter or anything
Your desired fit points of the pads:
Reach: 41.7
Stack 62.7
Stack and reach of the Shiv is al follows (assuming you are considering the triathlon Shiv):
S - Reach: 38.5
S - Stack: 51.5
M - Reach: 40.5
M - Stack: 54.0
Note that these values are measured to the point where the fork tube exists the head tube. As a result, you have to add the stem+aerobar dimensions to reach the pad stack & reach. Typically, this adds 6-9cm to the reach for the stem length. As for stack, depending on the aerobar it adds at least 2cm (the specialized bar adds even more), and this can be further increased using spacers.
Looking at your numbers, it seems to me your pad reach is relatively short, and will require the pads to be slided back considerably for the size M. However size S would require a considerable amount of stack spacers to reach your pad stack. In both cases, you have enough room to lower the pads if desired. What size you prefer is up to you as both are able to satisfy your fit requirements. Having a short stem tends to result in a more ‘nervous’ ride, so size S might be better?
Once you factor in the high stack bars the Shiv comes with it turns out that you would be slammed on a Medium. So it’s better to go for a small so you have room to adapt your position with time.
Another nice option would be the Felt B-Series 51
Or Cervelo new P2 54
Scott Plasma4 M with a low stack bar
The only rule when going for a modern superbike seems to be “get a small”. When I bought my Shiv I didnt realize how much stack the standard aerobar had and could not get that low, even though everything was slammed. Now I bought a small one instead of a medium. Everything still slammed, and using Uberhund aerobars with absolutely minimal stack. And a 110mm negative (-35) degree stem. Yay, superbikes.
Check out the thread “death of long and low geometry”.
