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TT Bike: Cervelo P2K vs. Kestrel Talon(10 posts)

TT Bike: Cervelo P2K vs. Kestrel TalonVimalakirti
Jan 24, 2004 1:28 PM
I went to my LBS last month to test out some mid-priced TT bikes. The two I liked best were the Talon and P2K. I was wondering if y'all had any thought on which would be best for my needs. I've never ridden carbon before, so in that regard the Talon felt pretty cool. But I have some concern about power transfer. I'm a fairly big rider (6'2", 170#) and I thought the Kestrel might be too flexy for someone like me. I know that the P2K is one of the most popular TT bikes out there. It does seem to be a little more aero than the Talon, but obviously doesn't have the same silky-smooth ride.

I'll be using this bike primarily for short distance tri's and duathlons, although I am signed up for an Ironman later this year. I'm hoping to win my age group in a few of the smaller races; which bike do you think can best get me there?
Check the fitasgelle
Jan 24, 2004 1:47 PM
Just a quick look at the tables for the two bikes shows the two have completely different geometries. For example the Kestral has a 73 degree seat tube angle while the Cervelo has a 75 or 78 degree seat tube (depending on how you position the seatpost head). It doesn't make sense that either could fit your needs as well. I would suggest you take a closer look at your position on the two bikes and get the one that fits you better. Everything else is secondary.
Check the fitVimalakirti
Jan 24, 2004 2:08 PM
Apparently the Kestrel also has a standard tri package that comes with an aerobar setup and a seatpost similar to the Cervelo's--the guy at the tri store seemed to think that I could get about a 76 effective seatpost angle on the Kestrel--still not as steep as the Cervelo, but steeper than the standard road bike. I felt, and the guy at the store agreed, that I could fit on either bike. They sell a lot of tri-specific bikes at this place, so I assume he knows what he's talking about.
Check the fitasgelle
Jan 24, 2004 3:26 PM
If he tells you a 73 degree bike can be adapted to 75 or 78 degrees with a forward setpost and ride the same, I would seriously doubt his credentials. You might be able to get the saddle in the same position but the compromises in other areas will make a bike with a forward seatpost ride very differently from a natural 78 degree bike. You might want to read some of the fit articles at:
http://www.slowtwitch.com/mainheadings/techctr/techctr.html
or
http://www.bikesportmichigan.com/bikes/difference.shtml
One other thingasgelle
Jan 24, 2004 3:30 PM
You might try asking this at
http://www.slowtwitch.com/cgi-bin/gforum.cgi?forum=1

You should get some responses from expert tri-bike fitters.
reversible seat posttuscany
Jan 24, 2004 3:59 PM
The Kestrel Talon has a reversible seat post designed to change the seat tube angle just like my Cervelo Soloist. It is designed to be used like this.

I think questioning his bike shops competence without knowing any details of how a given bike works shows a lack of knowledge on your part.
O.K. I don't know what I'm talking aboutasgelle
Jan 24, 2004 4:27 PM
O.K. I don't know what I'm talking about. Ignore everything I wrote. Of course, the difference between me and the salesman is I raised some questions in response to a query and never made any recommendations, and the salesman is recommending a buyer puts down, what, over $2000 on a bike.

Obviously I don't know anything about the bike shop's competence. That's why if you read what I actually wrote, you'll see I didn't say anything about it but raised my doubts. I don't see the harm in the OP's doing some background reading and satisfying himself that he believes what the salesman is telling him. In that vein, if anyone raised the issue of the advice from the shop, it was the OP. By asking his questionss here, he showed that either the shop wasn't answering his questions or he didn't trust their answers.

Finally, no one has answered my original question of how two bikes with very different geometries (beyond the seat tube angles) can fit the same person equally well.
O.K. I don't know what I'm talking abouttuscany
Jan 24, 2004 5:13 PM
Asgelle, maybe my reply came back a little harsh. I apologize if this is the case. You did question his bike shop professional's credentials which to me is the same as questioning his competence.

As far as different geometries I have had a 54 cm Trek, a 55 cm Litespeed, a 56 cm Seven, a 56 cm custom Seven, a 55 cm Klein compact, and a 56 cm Cervelo Soloist. After I made adjustments all have fit me perfectly. These bikes all have different top tube and seat tube lengths and seat and head tube angles.

Not all bikes will fit everyone but many different bikes will fit many different people with proper fitting.
Fit and PerformanceJon Billheimer
Jan 25, 2004 11:04 AM
The issue perhaps is not whether both bikes can be made to fit. As long as the rider has relatively normal proportions they probably can be. There are two other issues in my opinion: 1) rider position and the power/aerodynamics tradeoff and 2)bike handling and weight distribution. The Kestrel with the seat moved forward to an effective 76 deg seat tube angle will place more of the rider's weight on the front end of the bike. This is because the Kestrel will have relatively longer chainstays and the rear wheel will be further behind the rider's centre of mass. Concomitantly, the Kestrel probably doesn't have as relaxed a head tube angle as the Cervelo, so more rider weight ends up over the front wheel. This might not be significant on flat courses, but can become quite significant on downhills in terms of the way the bike handles. Also, one should probably experiment with several angles to determine at what hip angle you feel the most comfortable and to decide how low you want to get. The lower the upper body position the more forward you're probably going to want to move the saddle in order to preserve your hip angle. So no, the Kestrel and the Cervelo are not equal propositions in terms of potential rider positioning and bike handling. You probably need to spend some trainer time on both bikes and try different positions to see what works best for you.

My own preference would be the Cervelo (since I own a Dual:)- ). I've got a pretty aggressive seat to handlebar height differential and consequently have my seat set at an effective 79 deg seat tube angle. In this configuration my weight distribution, from rear to front, is 52%/48%, which is not too bad. On a P2K or a P3 the distribution would probably be closer to 55%/45%, which is ideal. So once you've tried both bikes with the setup which you prefer you should probably then check out your rear to front weight distribution. This will effect bike stability and handling.

Hope this ramble helps:)-
Fit and PerformanceVimalakirti
Jan 26, 2004 9:03 AM
Thanks for all your replies. . .

First of all, yes, I was a little skeptical about the salesperson's pitch to me. I had the impression that he was trying to move some old merchandise off the floor (it was a 2003 Kestrel), so he was pushing the Kestrel pretty hard. And they can barely keep their P2K's in stock, so obviously he had less reason to hype the P2K.

I did have some suspicions with regard to weight distribution on the Kestrel. I currently ride a Cannondale CAAD 4 frame w/Ultegra, and with clip-on aerobars for triathlons. I feel like I'm putting way too much weight on the front, and I'm looking forward to converting the bike back into my permanent training/crit racing bike.

As I said, I test rode both bikes and they both felt good. But it's hard to get a good feel for so many different factors in a 15 minute test ride. Mostly the ride on carbon felt very, very different than all the other bikes I tried--and I had trouble with the handling on all the bikes I tried, mostly since I'm used to my Cannondale road bike, not a TT bike. I'm leaning towards the P2K, just because of the raves it gets from my tri and TT friends. But I think it would probably take me a couple of weeks on either bike to really get a sense of their strengths and weaknesses.

Are there any other carbon TT bikes out there besides the Talon that cost less than $3,000? I know there's the Kestrel KM40, but it's a little pricey and only comes in two sizes (56 would probably be too small for me). One thing the salesguy at the shop said did make sense--on the bike leg of an Ironman, you don't want to get bounced around for 6 hours on an overly stiff al frame. Do any of you have experience doing long, long rides on a P2K? How did you feel afterwards?