A lot of Cervelo enthusiasts who are enthusiastic about the new P5 are, to put the best face on it, sanguine about the aerobar option. Doesn’t tilt. Armrest don’t expand as wide as many might like.

What we do note, with today’s launch of the P3X, is that you can take this bike’s aerobars and drop them right into the P5. Bravo! Cervelo has also made it pretty easy to do this.

The front end of the PX3 is available for the P5. I sense that the details are a little in flux, such as, the price for this. Will the dealer take the old bar back for credit? Do you want to keep both front ends?

Honestly, should you choose to purchase a P5 which – to refresh memories – is either $7,500 or $12,500 – I think there’s a very good chance your LBS will perform the swap causing you minor financial pain.

Making these bars cross-compatible was an engineering feat, but there are also inventory considerations, as well as: cost; what the exchange policy is; and what happens if the market makes a firm decision on one bar over the other? (Everyone will need to exercise a little patience as this plays out.)

It should be an easy swap, because the pursuit bars are not involved, and the shifting on all the bikes is electronic. I pulled the aerobar out of the P3X and what remained attached, coming down from the seat posty Speed Riser, was an electric wire and there was a connection right there (see schematic below).

Same with the P5’s aerobar. So, unplug the wire from the old aerobar, plug it into the P3X aerobar, slide the new aerobar in… done! I can’t imagine this taking more than a minute.

On the one hand, you might think there’ll be a rash of swap-outs, with a bunch of leftover P5 front ends. I’m not so sure. I think it’s possible you may see swap-outs in the other direction. There’s no way to know until the market speaks. Here’s the difference between these two front ends.

Both front ends are UCI legal. P3X front can be level, or there can be tilted up 5, 10 or 15 degrees. Its pad position is more width, height and length adjustable.

Each bar has the built-in capacity for accepting front hydration between the arms. Above you see it on the P3X's bars and the easy way to know which bar is which is the P5's aerobar has a monoextension. That monoextension has a pair of bossed built into the mono part of the extension. the P3X has the traditional pair of extensions, and a removable bridge that slides down to the base of the extensions and has a water bottle boss on it. Above you can see how the water bottle or fluid hydration system would mount. The other boss is that middle among the 3 bolts between the armrests.

The P5 aerobar comes with a choice of extensions, 30° ski bend is standard, but also S-bends and 50° are options. The P3X only comes with the standard upturn, 35°, but this bar accepts the 22.2mm outside diameter typical of almost everybody’s extensions.

But it’s not all in favor of the P3X front end. The P5 front end is 100 grams lighter. When the front ends are set up the same way – no tilt obviously – Cervelo claims the P5’s aerobars are lighter, though this might be a combo of the aerobar and the pursuit bar.

While the P3X’s aerobars allow the pads to go wider than you can get on the P5, the latter’s bars allow the pads to be placed narrower. It integrates the Di2 junction into a pretty nifty location, and the confluence of the junction and routing presents an integrated aesthetic.

Just, here’s a pic of me riding the new P5. I’ve got the pads adjusted out as wide as they’ll go and, as you see, it’s wide enough for me, but I’m a jacket size 42 generously (I’m more 42 than 40, but I’m on the 40 side of 42). This is how wide I’m not.

So, the fellow who’s coming to tri with wider shoulders may find the need to move his pads out. This is a viable reason to want the P3X’s aerobars.

It’s not just the adjustability in the Z plane. It’s also pad height and pad fore/aft. The P3X’s bars are very adjustable, as in, Speed Concept adjustable. Below is a Cartesian representation of the old P5X adjustability versus the new P5. If you mosey over to the P3X write-up from today you’ll see that Cartesian graph showing the old versus the new PX series bikes.

Note that the P3X retains almost all the adjustability of that the P5X gives you. Most of you won’t need the additional height range the PX series offers, but a lot of you will need the fore/aft.

As you see below, there’s a lot of fore/aft in the extension: 95mm.

But there’s only half that fore/aft range in the pads, and that is where some of you will find yourself hamstrung.

All that said, I like the new P5 aerobars fine. The available range fits me well. I don’t ride with upward tilt in my aerobars, so I don’t need the P3X tilt; the P5 bars are simpler, lighter; and I like the 30° extension angle that is the default option on this bike.

As I noted in the P3X write-up, there’s a $400 charge to move to a bar not on the bike you’re purchasing. What’s not quite worked out – or if it is I didn’t understand it – is what happens to the old bar. I get the sense that it’s $400 and you now have 2 sets of bars. Or, if you relinquish the bar you don’t want, what’s the credit back? I think this’ll depend on your LBS. My guess is that if you’re dropping between $7,500 and $12,500 on a new Cervelo tri bike, your LBS is going to be somewhat malleable on that.

What we don’t know is what bar the market will prefer. Or, which among the new Cervelo bikes. It would not surprise me if I see a lot of P5s with P3X bars on them. However, I could see a lot of long distance pros riding the P3X because of the storage, and if they don’t ride with tilt (most don’t) and if the P5 aerobar fits (in most cases it will), why not ride the P5 bar on the P3X?

This’ll be interesting to watch.