Just curious as I’ve never ridden one, does the suspension-like quality of a flexible beam affect pedaling at all? It seems like the saddle has to bounce up and down a little bit with each stroke.
I had a P5X and a PX and never really noticed much. I did notice some isolation from the road from not having a seat tube but not really any additional comfort from beam flex. Those were solid bikes though and beautiful to ride, I regret selling them. I actually notice more, and see more actual movement on my Trek Speed Concept Disc.
Just curious as I’ve never ridden one, does the suspension-like quality of a flexible beam affect pedaling at all? It seems like the saddle has to bounce up and down a little bit with each stroke.
I’d be more concerned with frame flex at the bottom bracket, resulting in lost energy propelling the bike forward. Put your front wheel against a wall, push hard on the outboard pedal, watch the bottom bracket move sideways. There are those who think this energy is not lost, but feeds back into the system as the bottom bracket springs back in place - I’m not one of them.
Just curious as I’ve never ridden one, does the suspension-like quality of a flexible beam affect pedaling at all? It seems like the saddle has to bounce up and down a little bit with each stroke.
I’d be more concerned with frame flex at the bottom bracket, resulting in lost energy propelling the bike forward. Put your front wheel against a wall, push hard on the outboard pedal, watch the bottom bracket move sideways. There are those who think this energy is not lost, but feeds back into the system as the bottom bracket springs back in place - I’m not one of them.
I wasn’t even thinking of frame losses like that, more like biomechanics of not having a stable platform to sit on.
I had a P5X and a PX and never really noticed much. I did notice some isolation from the road from not having a seat tube but not really any additional comfort from beam flex. Those were solid bikes though and beautiful to ride, I regret selling them. I actually notice more, and see more actual movement on my Trek Speed Concept Disc.
Did I see it a past thread that you had a P5 disc and a PX, and chose to keep the PX? When you say “isolation from the road”, does that translate to less discomfort in the, uh, under-carriage area on long rides?
I’m assuming you mean the bottle on the underside of the tri bars? That was for an IM and I run three nutrition bottles so was about function but if not doing an IM I run an empty Xlab Torpedo in the hope it is a more aero shape. But no I’v done no testing.
No, I actually meant the downtube bottle. I do believe that underside BTA bottle is aero, I’ve tested it but it fell apart the first time I raced it and I left pieces of bottles and cages everywhere, so I never rebuilt it. Also TJ used to run it this way.
I’m assuming you mean the bottle on the underside of the tri bars? That was for an IM and I run three nutrition bottles so was about function but if not doing an IM I run an empty Xlab Torpedo in the hope it is a more aero shape. But no I’v done no testing.
No, I actually meant the downtube bottle. I do believe that underside BTA bottle is aero, I’ve tested it but it fell apart the first time I raced it and I left pieces of bottles and cages everywhere, so I never rebuilt it. Also TJ used to run it this way.
Wow, very interesting. Like most of the country, we are getting some real hot weather here in Florida. Great idea for carrying another bottle! -
Yes I think it would for sure. I believe that the added comfort I felt was more attributed to not having a seat tube rather than any flex or suspension from the ‘beam’… which is quite stiff.
Yes I had the P5D and PX at the same time… l ended up selling the P5D and keeping the PX but then later sold that as well for something different. More had to do with lack of local Cervelo dealer support than the bike itself.
How did you enjoy your time with the P3X? What did you move on to?
The P3x was a fun bike to ride, really liked it. It was a touch faster than my Plasma which I did A LOT of mods to make it pretty close to a P5-6 bike only testing. I wouldn’t say it killed my plasma but was a bit faster.
I didn’t move onto anything, got an injury that force me out of competing, ended up selling it
I went from the Cervelo P2k to the P3X, same saddle on both bikes. I would say the P3X is slightly more comfortable, but the difference is so small that it should not be the deciding factor in a purchase.
My friend has a Pearson bike. Graeme Pearson was the first person I thought of to build me a custom mantis set of tri extensions before they came into vogue. He comes from New Zealand and just across the ditch as we call it in Australia, seems adventurous with what he likes to do in carbon and did me a custom set at a fraction of price you can buy a stock set now…
This bike looks fucking dope. Kudos.
Hate the flexing of the beam, but man this looks hot.
It’s worth noting that back then we were riding 21-23mm tires at 120psi vs 25-28mm tires at 80psi.
In my experience changing to wider wheels/tyres with lower pressures does more to improve comfort that anything else. That with the caveat that the only beam bike I have ridden was a softride in about 2009 for all of about 30 miles.