Planet X Pro carbon Track

I've been looking at buying a second hand track bike for racing, mainly for use at Herne Hill (but want to have the option to branch out to Lee Valley etc). I've found a lot of Planet X Pro Carbon track frames out there, and wanted to know people's opinions on them, as I can't find many reviews online. Obviously they're fairly cheap compared to some higher end carbon frames, and also older. Want to know what people think about them, specifically about their stiffness and sizes:

• I've heard from some people they're pretty flexy: is this true? I'm hoping to race on it competitively, so want something stiffer for the high end power sprints.
  
• I'm about 80 kg and 189 cm, would the size large frame be suitable (their biggest one)? Its reach is only 20 cm longer than my roadbike's, compared to a Dolan DF4 59 cm where the reach is 50 cm more. I'm worried that as I race more I'm going to want to stretch out my reach, and might be limited
  
• Anyone got any other opinions/experience on them, and if they're good value
  Or can anyone suggest any alternatives?
  
  

I quite like how they look too, which obviously helps

I raced one for a couple of years at HH. I went from an alloy Dolan to it.
It was light and good value at the time. I don’t recall it being overly flex but I was not a big strength rider being more of a spinner, nor was I any good! I am about 6’1” and was about 90kg so rode a large.
At the time it was a good value frame for a fairly crap middle aged racer. If you are aiming higher you may want to invest more. I did spend proportionately more on relatively decent wheels and tyres though.
I sold mine to a club mate and it may still be circulating HH. Overall it was a good frame for what I needed, if i was doing it again I’d consider one (or a steel colnago which is obviously loads more cash!!).

Had a couple, and I'm about the same height (and was the same weight 😂) as you.

Yes, they're flexy. That being said, realistically, how much power are you putting out? If you're a 1600w+ sprinter, you'll notice it, if you're a regular human in the 1000-1200w range, if you're not winning races, it won't be the bike flexing that's the problem. There have been plenty of people riding them at national level in the past in endurance events.

Don't really think I can answer about the sizing question, as that's such a personal thing, but that being said, 59cm track frames are really hard to come by unless you want a 220mm headtube, so you may end up having to pay for a high end frame if that's what you want. Only affordable option out there I can think of would be an XL Hoy Fiorenzuola, but those are SUPER rare, unfortunately (such a shame as they're incredible frames for the money!) Those are even longer than the DF4 though, with 538mm reach (60cm TT).

If you're not so fussed about the smaller sizing, the Felt TK2/3s are pretty much exactly the same geo as the Planet X and way, way, waaaay stiffer. And they go for a song second hand, which is nice! Bought one a couple of months ago, and it's easily as stiff (if not stiffer) than my Pinarello!

I had one for a while and with my meager power output it did not feel flexy. Mind you I think my best lap average was 48km/h. However it just felt kind of flat and not very confidence inspiringly lively like my carbon fiber road bikes. I have had an alloy Cinelli Mash and steel track frames. To be honest I like the steel one best. It is stiff and transmits power best.

Hmm, I did actually just top out at 1700 W a few weeks ago, so I may keep browsing (haven't seen that many Felt Tk2/3s on my searches though). Most likely I will just stick to the hire bikes for a while....

Out of interest, how much of a difference would the stiffness actually make: Is it quantifiable in terms of power/speed loss? Or is it just feeling fast more than anything?

It'd be a tiny amount slower, you could probably find a measurable difference, but aerodynamics would probably be a bigger factor, so you couldn't be sure (we're talking like a hundredth of a second in flying 200 here - doesn't sound like much, but those hundredths are hard won for true sprinters!)

Personally, I'd go for it over a hire bike - the geometry is so much better. They may be flexy, but they're great value starter bikes. Those Condors are so upright they may as well be Dutch city bikes 😅

How about this?

https://www.lfgss.com/conversations/381454/#comment16760484

He's worried about flex in a deep aero carbon frame... 😁

They are flexy though

That may well be the case but if that's a concern then a 60cm 531 lugged frame is not going to be a viable alternative

Thanks for all the info so far, I'm trying to figure out if it's something I just wouldn't have noticed if I hadn't heard about it, or if it's really quite obvious.

For example, I went from an alloy 2016 Synapse to a HiMod SystemSix, where I really could feel the stiffness difference. Where would you say the rental track bikes and the Planet X Pro Carbon Track sits on that (admittedly sparse) scale? And what's the stiffness value for money? (Would pricing up actually be worth it to gain stiffness?)

What track bike do you currently race on?

I don't, I've only ever ridden on the rental bikes (Fujis at Herne hill and Condors at Lee Valley), so am deciding whether to buy one, and if so then what.

You need to base it on looks. And buy loads of other bikes to go with it.

They're way less flexy than the HHV Fujis if that helps? Planet Xs are pretty ubiquitous, so if you're unsure, you could just ask someone at the track for a go?