VegasJen

So I have several triathlon bikes in my stable. My favorite thus far has been my 2015 Specialized Shiv. I just really like that bike, it feels like it was designed for me. And it's fast. Prior to that bike, I was riding a Ridley Cheetah. It's an older bike but decent enough, it just never really felt like it fit me well.

But a couple months ago I ran across a Craigslist ad for a Cervelo P2. The bike was listed as a parts bike because the girl that had it believed the CF handlebars were cracked. I looked at it and got it for a very reasonable price. I ended up buying it more on a lark than anything. I don't think the bars were cracked, but I replaced them anyway with a different set up. I also replaced the original front fork that had been cut super short with one that gave me another couple inches of stack.

So I'm finally getting this bike sorted out. I don't think it's totally there yet, but close. Yesterday I took it out for a ride. I took it on a known course I've ridden several times in the recent past. Conditions were near ideal. A little warmer than I prefer, but no wind. I've ridden this same route in similar conditions but my best average for this 36 mile route was 18.1mph. Until yesterday.

Yesterday I rode that same route at an average of 18.5mph. I was shocked. That is not an insignificant differential. Nearly a half mph difference. Extrapolate that out over the course of an Olympic distance triathlon and we're in the neighborhood of 4-5 minutes. At least for me, that's almost half a kilometer on the run.

As much as I like my Shiv, it now has serious competition. And the Cervelo is just a basic older CF frame with shallow alloy wheels and butyl tubes. I won't be doing a "comparo" any time soon, but maybe when it cools off in a couple months I'll do back-to-back rides between the two and get a more accurate comparison.

VegasJen

HOLY CRAP!

I was tinkering with it a bit more. Got my stack dialed in. I also swapped out the alloy wheels with a set of Bontrager/HED carbon Aeolus 5.0 wheels and TPU tubes. A couple minor adjustments to the reach/bar height and seat angle.

Just damn!

Exact same route as above. 19.8mph average. That is *by far* my fastest average EVER. And this route isn't exactly flat. Total of 660ft of elevation gain throughout. It's a loop though, so I also have 660 feet of decline. But still, at least for me,that's flying.

VegasJen

On a side note, I did lose one of the TPU tubes in this ride. Fortunately, it was the rear. Also fortunately, it happened while at the crest of a hill before I picked up any speed. Even more fortunately, the crest of that particular hill is the point before my single fastest descent when I frequently hit about 30-32mph for almost a half mile. I shudder to think of how bad things could have gotten had it been the front tire that failed at max velocity.

Upon inspection, the tube failed right at the joint between the main tube and where the valve stem is bonded. No idea what could have caused it. It was a brand new tube, installed yesterday and aired up to 90psi. It was a rapid loss of pressure, I actually heard it pop. But no idea why though. I didn't hit anything with the tire before the failure.

VegasJen

Yet another data point. Today I did a local club event on the Cervelo. This is the same bike course I did for Rage on the Shiv back in April, and then another club event in June on the Cheetah. In both of those sprints, I finished the bike course in 47 minutes and change. To be fair, the one on the Shiv was a windy day and I had my 80mm wheels on which I think may have slowed me down by a minute or two, so best case scenario, potentially 45 minutes. Today on the P2, same course, 42 minutes and change.

I do not know why this bike is so damn fast.

_ForceD_

That is some quick riding that’s for sure. But one thing I’m confused about…you mention that the course is a 36-mile long loop, and it was used for a “sprint.” That’s longer than an Oly bike.

Dan

VegasJen

OK, I probably wasn't as clear as I should have been. I have one route I use where I live that's 36 miles. The other route I used for comparison is a route in Las Vegas used often in organized sprint triathlons. Two totally different routes.

VegasJen

So under the auspices of "this thread is worthless without pics", I present to you the Cervelo in question. My research shows it's a 2011 P2.



The wheels on it in this shot are a new-to-me set of Reynolds 41mm carbon wheels I picked up yesterday for an extremely good price. As it sits, even with the wheels, replacing the fork and other maintenance/upgrades I've done to it, I'm into this bike for just a bit over $1000.

tempocyclist

Nice. The old Cervelo P-series of TT bikes were known for being very slippery. A good purchase! Position on the bike also helps a lot, so perhaps your body position is slightly better on the P2 also.

VegasJen

Ya, I'm trying to figure out why I'm so much faster on this than I am on my Shiv. I'm hoping to get the Shiv back out here later this week and see if it's actually the bike or maybe some other factor I haven't identified yet.

_ForceD_

There is a lot of stuff attached to that bike. Rather large hydration system, Bento bag, unused bottle cages, etc. Don’t get me wrong…it’s a nice bike, and I like it. But stripped down you might find it even more aero, lighter, and faster.

Dan

tempocyclist

This thread needs a photo of the Shiv too for comparison, and because bike pics are always a good thing!

VegasJen

I get that. I have it set up for distance, I just don't have anything on it right now. Believe me, when I'm heading out, there are no empty bottle cages. I don't normally run anything in the hydration tank, yet, but that's there for when I do Ironman (if I decide to use this bike).
I have posted elsewhere but since you asked. (and this is an updated photo anyway)

VegasJen

Today I did a little work out in the garage. Not so much on either of those bikes, but a different bike I'm getting ready to sell. But while I was there, I did take some time to compare measurements.

So the biggest single difference I have discovered is that even with the saddle moved as far forward on the rails as possible, it is still about one full inch further back on the Shiv than it is on the P2, and I still probably have another 1/2" more travel available on the P2 if I want. The only other significant, relatively speaking, difference is the Shiv has 165mm crank arms to the P2's 170mm. Beyond that, the distance from the nose of the saddle to the bar end shifters is within 1/2", as is the height of the aero bar pads and the distance from the saddle nose to the arm cups. These two bikes are almost identical.

Tomorrow I'm going to take the Shiv back out on that same 37 mile route and see what kind of time I can do there. My previous best on that route riding the Shiv, I managed 18.1mph. I've done it twice now on the P2 and both times I averaged over 19mph. One of those times was 19.8mph.

VegasJen

Well, Sunday didn't work out because I had a mechanical failure. I didn't ride yesterday so the plan was to go out today and duplicate the ride. Unfortunately, I had a flat during this ride. I was able to stop and restart my time reasonably accurately. Also, my Velo counted both mileage and time correctly. Because of the puncture, I did not feel comfortable completing the entire 37 mile route, so I shortened it to 23 miles. Not exactly apples to apples, but it was, more or less, the same route, only cut short.

Even so, I was only able to maintain an 18.8mph average on the ride. It did include my big climb (that's a hill that averages 4* with small sections up to 6*) that's just over a 1/4mile long, which I often do mashing out of the saddle. The rest of the route is much more gently rolling hills or flat, so it could be argued that my average pace could have been slightly higher if I had done the full route and had more time at that higher average pace.

Having said all that, the one thing I can't get past though, is that I still felt like it was much more effort to maintain this pace than it is on the P2. This is just a WAG but I probably spent 20-30% of my time in zone 4 for this ride, as compared to maybe only 10% in zone 4 on the P2. And I feel every bit as exhausted after just 23 miles today a I do on the full 37 mile route when riding the P2.

So where is this extra 1mph? I mean the Shiv still feels fast. And it's definitely faster than my old Cheetah or any of my road bikes. But the P2 is a different animal all together.

VegasJen

Yet another data point. Today I took the P2 out on the same route as above. The results were much more comparable to the Shiv than previous rides. My average today was 18.9mph over the same route. That might seem like a dead heat but conditions were a factor today that weren't a factor the other day. In particular, I started out with noticeable wind that increased quickly over the short duration of the ride. In my previous ride, I had almost no discernible wind to deal with, probably <10mph. However today I started out the ride in 10-15mph wind that only increased as I was out. In the short 75 minutes it took to complete the ride, my seat of the pants estimation is wind had picked up to a steady 15-20mph with the occasional gust of 25mph.

Not really sure how much of an affect it had overall as the ride is something of a loop, so a headwind in part of the ride is a tail wind elsewhere. I will say in one particular stretch of relatively flat road that's around 3 miles I was comfortably riding at 25+mph with a tailwind. Now I can often sprint to 25mph in short bursts, but to be able to hold that pace, much less comfortably, that's pretty significant.

I still have a goal of getting the Shiv out and back on that 37 mile route without incident for a good data point, but as of yet, the stars have not aligned and the cycling gods have not smiled on me.

I definitely think seating position is playing a factor in the difference. As such, I did an internet search and there is a Shiv seat post that positions the saddle even farther forward than the standard post allows. I think I'm going to track one down and give it a try. I should be able to pick it up for <$100, and if that's the case, then I should notice some parity between the two frames.

Wildwood 

good tracking your speeds accurately. there is a guy on C&V with a large collection of road bikes, who ran many of them for an hour or more. It was his 19MPH Challenge Run, pretty flat in Utah. He would play with wheels and such seeking a 19mph average on those he thought should be the fastest. It was fun to read, like your updates and revelations. not sure he picked it up again, post knee surgery.