Hi Eric,

Hoping for the right advice ;-)

I'm 178cm with an 86cm inseam, don't have my old TT bike or numbers (mistake) but ride a fairly orthodox TT position.

Found a 56cm P5 Disc that I'd love to grab but concerned fit would be limited as I'm prob more suited to a 54cm. Wanted to check with someone who knows a hell of a more than me before making a call either way.

Thanks mate.
Nathan

You should get a fit.

I agree about getting a fit, but one fitter could have you on a 54cm but if you saw me for a fit I’m sure you’d be on a 56cm, especially if by orthodox you mean long and low.

Do you have any pics on your tri bike?

E

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Hello

Looking for advise on M vs L size for the following bikes if possible. Thanks!

Current bike:
2010 Giant Trinity Advanced SL2 / Size L

Current sizing:
seat height = 813mm
padY = 654mm
padX = 457mm

height = 185cm
inseam = ~890mm

Looking for:
Cervelo PX series
Dimond (Marquise)
Canyon Speedmax CF

For the PX, you’d fit on a M, L, or XL, but I’d recommend a size L.

For canyon, see Ian’s thread here on ST.

Eric

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Hey Eric,

Stack= 587, top of pad
Reach=441, to back edge of pad
Saddle= 679


Could you help me with sizing on both a P5D and a P Series?

Thanks in advance!

hi, thanks for reaching out.

I think you're a pretty clear cut 51cm on both the P5d and the P-Series. Let me know if you're having trouble finding a 51cm and if so I can go into more detail.

Eric

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Hi Eric,

I'm looking for a Cervelo P3/P-series, but I'm not sure what size? Will fit me best between 54 and 56, please advise.

Height 174cm
Inseam 85cm
Torso 58cm
Arm Length 62cm

Saddle Height 765mm
Pad X 422mm
Pad Y 685mm
Pad Z 190mm

Thank you
Gopp

hey, thanks for reaching out.

With a pad stack of 685mm at your reach of 422mm you're off the charts high, IOW that's a very high stack for that amount of reach. From a reach perspective, you look to be in between a 51cm and a 54cm... if you got 10mm longer you'd hit the back end of the 56cm.

How sure are you on your numbers? I'd expect you to need more reach than you are currently using, or less stack. Don't get me wrong, the P-Series is extremely flexible and will fit whatever position you come up with, but right now something doesn't seem right so let's sort that out first.

Make sense?

Eric

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Hi Eric,

Yes. That's make sense. However, please let me correct a mistake on Pad Y number as below. I've got these numbers from a sizing machine by bike fitter last year. I've never had Tri bike before.

Height 174cm
Inseam 85cm
Torso 58cm
Arm Length 62cm


Saddle Height 765mm
Pad X 422mm
Pad Y 680mm
Pad Z 190mm


As seen the body figures. I might have long-leg and short torso. Please advise.


Thank you
Gopp

Hi Eric,

I'm also trying to see which bike/bike size to go with. I did a bike fit last year for my Cervelo P3 54, ended up with a 120mm stem angled up 7° to be able to get enough stack for long distance comfort.
This same bike fitter is recommending a size 58 Cervelo P5d.

Which frame sizes do you think I should go for (fit coordinates attached) on the P-series/P5?

Thanks

With a pad stack of 704mm and a pad reach of 416mm you're in the same boat as the previous guy... off the charts high. You're 25mm "behind" the minimum reach of a 58cm P5, and also 5mm too high. The minimum would be 700mm stack and 445mm reach.

I'd have to see a picture of you, but I bet if we just rotated your whole system around the clock face, forward and down, you'd hit a 58cm P5d just fine.

Have you considered changing saddles, maybe a PN 3.0?

Eric

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Same situation... off the charts high and left. At a pad stack of 680mm you'd have to come forward to 432mm of reach to hit the back end of a 56cm. At a pad reach of 422mm, you'd have to come down to 662mm of pad stack to hit the top end of a 54cm frame.

It all depends on where your position needs to go or where it might go in the future... I lean towards getting longer and lower together, not just lower, and so the 56cm will probably be better for you.

Eric

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I'd say I have long legs and a shorter torso, which seems to cause headaches fit wise ;)

I think the saddle position is already pretty far forward (see fit pics).

In my case, by looking at the cervelo bikes geometries, wouldn't a p-series 56 actually fit me better? They seem to have more stack for less reach.

In looking at your effective position, ie. where your hips actually are in relation to the BB, I'm comfortable with you moving your whole system forward 25mm in order to hit the back end of a 58cm P5d.

make sense?

E

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Hi Eric,

Your expertise has cleared all my doubts. Now i have the confidence to go for it based on your advices. You're awesome Eric.

Thank you
Gopp

It does indeed.
I'm pretty happy with the position though (I've held it for 7 hours straight without any particular pain so it's very comfy, and qualified for Kona so it must be somewhat fast), so buying a bike for which I'll have to change my position is a bit of a leap of faith.

Hi Eric

I’m looking at a P3x. I don’t have stack height measurements but I’m 180cm tall with 83cm inseam. I ride a 56cm Madone. What’s your recommendation for size on the P3x please?

Thanks!

All things being equal I could see you on a 56cm PX… do you have any more context or pictures of you in a bike?

Eric

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Thanks. So would that be a medium P3x? The beam bike.

Yes I can get a side on photo? Is there a way to direct message you?

Thanks
Aidan

Yes you can send me a PM

E

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I'm in the market for my first proper tri bike. I'm looking at getting the base model of the Pseries and want to verify what size I should be buying. I've been riding the Giant Avail size medium and the Giant Liv Envie size medium. I have had a proper bike fitting on the avail but not sure if these are transferrable to a tri bike?

Can you send me pictures or your fit report?

Eric

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Sure, I've attached the fit measurements. Thanks.

Hi Eric,

I just had a pre-fit done as I am looking to get my first tri bike. I'd be looking at the P-Series.

Pad X: 489
Pad Y: 667
Saddle height: 775

Thanks!