Agreed Jonnyo, it’s why I’ve kept my P3 vs upgrade to any “super bike”.
My R5 has the BB30 & for life of me I feel no difference and now have more complex crank and power meter configurations. In turn i stay with Powertap for power. I would like to crank based power for my 303 race wheel configuration but just a pain in ass to change now. And FSA carbon no-no work with Stages. Garmin vector worries me as I change pedals every 3 years or so with wear. So maybe power tap has BB30 to thank!!
The R-series uses a special lower headset bearing.
A significant increase in fork stiffness and strength, and a matching decrease in weight, are the reasons we invented the 1 3/8" lower steerer. Bigger ( like one point five inches) can be too stiff, and adds weight to the fork and frame. As we’ve engineered better and better forks over the years, the right sized steerer in the right application is the result. We call this Evolved Steerer Design. More info can be found here: http://www.cervelo.com/…-steerer-design.html
As far as I know, no other bike companies have adopted this fork diameter yet (though they could), so I believe this lower bearing is currently a Cervelo-only item.
Edited to add: Good news: A little Googling suggests that Specialized has a similar size bearing. Wheels Manufacturing offers a replacement: http://wheelsmfg.com/...balls-and-races.html
Edited again to answer your question about specs:
49mm OD x 37mm ID x 6.5mm36 x 45 degrees
Cheers,
The R-series uses a special lower headset bearing.
A significant increase in fork stiffness and strength, and a matching decrease in weight, are the reasons we invented the 1 3/8" lower steerer. Bigger ( like one point five inches) can be too stiff, and adds weight to the fork and frame. As we’ve engineered better and better forks over the years, the right sized steerer in the right application is the result. We call this Evolved Steerer Design. More info can be found here: http://www.cervelo.com/…-steerer-design.html
As far as I know, no other bike companies have adopted this fork diameter yet (though they could), so I believe this lower bearing is currently a Cervelo-only item.
Edited to add: Good news: A little Googling suggests that Specialized has a similar size bearing. Wheels Manufacturing offers a replacement: http://wheelsmfg.com/...balls-and-races.html
Edited again to answer your question about specs:
49mm OD x 37mm ID x 6.5mm36 x 45 degrees
Cheers,
Thanks for all this info…now that I am sorted away, and since I have curious engineering background (albeit electrical/RF/Comms), I assume the reason you can use symmetrical 1 1/8th on the P3 vs the R series is because we won’t be riding our P3’s on Paris Roubaix and other assorted GC dream destroying cobbles in France and the Ardennes
That, and the priorities are different between the R-series and P-series. More emphasis on aero for the P-series, so the smaller bearing reduces the frontal area of the head tube.
That, and the priorities are different between the R-series and P-series. More emphasis on aero for the P-series, so the smaller bearing reduces the frontal area of the head tube.
Cheers,
On the new P3 I feel like I am on a highly upgraded version of my original white Kestrel 4000. I saw a picture of Mark Allen riding it in Nice in 1990 and was first on the local buyer list in 1991. Carbon bikes have come a long way, but that thing had a narrow head tube:
Unfortunately, mine developed a crack so I got a Kestrel 200 SCi a few months before Penticton 1991. Also very narrow frontal on that bike…that was IM number 1…thanks for getting me to the start of IM #26. Everything is mechanically good to go. After being cooped up in airplanes and hotels for 2 days with mechanical and rain related forced taper just went did 40K of riding with 2000 ft of climbing and everything is rock solid now:
It’s a small world - I worked for Kestrel as a tech rep from roughly 1989-1991.
Thanks for the photos and a trip down memory lane!
Cheers,
6 speed
Mavic GP4 rims
Down tube Dura Ace Shifters
53x39 with 13-18 corn cob (wtf was I thinking doing IMC on that?)
Cinelli base bars
Profile Clip ons
Selle Italia Turbomatic saddle
Oakley Factory Pilots
Taper Squared UN 71 BB
172.5 Shimano Ultegra cranks
Quill stem
Kestrel 200 SCI frame
I still have that bike bolted to my computrainer upgraded to 8 speed with profile base bars and visiontech clip ons and 13-23 cassette and 170 Sinz taper square 110 bcd BMX cranks. I believe taper square BB was replaced around 3 times. Kestrel gave me a warranty upgrade to the frame in 2000 as it had developed a crack by then.
Sorry to revive an old thread but I took my 2014 P3 apart to clean the headset and found that the bearings were seized to the frame and they basically disintegrated while I was taking them out. I went to my LBS but they apparently ordered the wrong size (41.8 mm) as they will not fit in the frame. I’ve found what I believe to the be correct part number from Cane Creek (HSS20130) but I was wondering if anyone can confirm that both the top and bottom bearings are the same before I order.
