Hello
I’ve got a planet-x stealth tt frame and I’d like to improve this base if possible.
If think it could mainly be done in the front of the bike.
I’ve got a flat carbone handlebar (progress pg-241) and an old school stem with spacers behind.
I thought about putting a more Aero stem, taking of the spacers and raising the bars. Maybe putting some angle on the bars also.
What do you think ? What else Can i improve ? (internal routing I imagine)
Thanks a lot
Ivan
You could replace the bars with something like a tririg Alpha.
Switching from S bends to ski tip extensions is almost always faster.
Try to clean up cable routing, maybe drill some ports and move it internally
What I would not encourage you to do is dump a ton of money into this project. That bike wasn’t that fast to begin with. You’re about 8 generations removed from a top of the line bike. Each older generation is 4-8w slower than previous gens depending on bike brand.
Let’s say your bike is 50w slower than the top 2-3 bikes on average. You may be able to get it within 25w slower. At some point you’re going to hit a wall.
That bike will never get within striking distance of a rim brake P5-3 or P5-6 and the rim brake P5-6 is still 10-15w slower than the top 2-3 fastest bikes
Hope that helps
Four things jump out:
Thanks, it helps a lot.
I ordered a New cockpit with more adjustability and ski-tip bars.
I move the bottle since I had the support.
For the wheelcover, not sure i could find it in France but maybe an old disc.
Is it usefull to take out the spacers behind the stem to keep the basebar Closer to the frame? (putting an inclined stem or more spacers behind the ski bars)
Generally risers are more aero than stem spacers (oval profiles vs a thick cylinder). That being said, place the base bar at the right position for cornering/climbing (typically where you would ride on the hoods with a drop bar), and then use the necessary risers to position the aero bars. Use the bento to smooth the airflow behind the stem.
Interesting, should I stop dumping money on my plasma 5 and finally buy that 2025 Cervélo p5 ?
I keep telling myself that it’s probably just as fast.
The plasma 5, iirc, was only a couple of watts faster than the plasma 3 if you had all the hydration front end stuff on.
What’s your average 40 OR 90k time and power and I’ll get back to you in a day or so with roughly how much faster the P5d is
Hard to say as the triathlons I do vary a lot. But for the last two flatish races (around 400meters of elevation), 39km/h over 80k and 90k @235Ap, 240NP.
don’t spend too much time on it, it’s really nice from you but I will probably get it anyway : 30mm tires are very appealing even if I’m not faster.
Also did Aix en Provence at 35km/h at 261 NP this year for 1200m of elevation, but it’snot very useful data as I was extremely cautious and accepted to loose a lot of time on the descents.
It’s hard to see everything, because of the dark and busy background…
A couple things I would add to the above…
I’d just do latex Tubes, conti gp 5000 tires and 88 mm Chinese wheels front and back which are about $400. That will get you nearly all the way there compared to a $6k current gen tt bike having compared this myself.
I actually suspect you’re not losing a ton with that setup if you aero position is decent.
Have a look at EZ disc in the UK, they ship to europe. Recommended them strongly
Am I looking for a needle in a haystack trying to find something at 80+ mm with greater than 23mm external width? Or just accept that the tire could sit anywhere from 1-3.5mm wider on each side?
It’s true that a lot of the cheaper Chinese wheels at 88mm aren’t built for greater than 23mm, as they aren’t current-gen specs.
25s will for sure fit though, I did this myself on my prior rim brake 88s, never tried 28s unfortunately.
Honestly, if you’re committed to using that perfectly fine rim-brake bike, I’d just suck it up and use 25s, they’re actually not bad - all us older folks raced with 23s for the past decade+ and we did fine. My 23s absolutely were no slower than my current 28s, but man, the chatter on rough roads is kinda brutal in comparison!
(For current-gen disc brake wheels, most race wheels fit 28s, like HED.)
Im a different guy, but my situation is a 2022 Speedmax with disc brakes.
Have been looking for a while for something that will accept 28s
Light bicycle has some 60 mm rims thst are 30mm external for rim brake, work with 28mm tires just fine and they stop pretty well too. I’d rather get two 60mm rims and run a disc cover in the back than run narrow 80+mm rims. Pretty diminishing gains over 60mm when you’re going fast anyway
Almost anything current gen will take 28s. Most new tt bikes shipped now come with 28s.
hed vanquish v62 is what my bike came with and it uses 28s.
I made an assumption on system weight which may skew the results :01-:02 here or there, but not more than that. 90km avg power = 235, starting CdA of .240 which is pretty typical when I get people in for testing
All these numbers are going to be in that +/- :15 range over 90km since I don’t know you’re starting CdA, that allows for some mild wind, elevation gain/loss etc.
10w apart that’s roughly 2minutes
15 apart is roughly 3:40
20w apart is roughly 4:50
If you’re starting CdA is roughly .235 then 20w apart is roughly 4:40 saved
Hope that helps
What about SRAM etap blips, go 1x aero chainring, 12 speed Shimano cassette. Cut of cable stops and remove front derailleur hanger.
Gotta be worth some watts
Great info
Thank you for posting
Man that’s too complex and expensive for an older gen bike.
