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Bike Upgrade, Change Size?
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I'm going to be upgrading my bike from Dimond Brilliant to Marquise and given I'm now a few years down the road from the original purchase and racing longer distances does it make sense to look into a larger fame for any reason? Or if it aint broke dont fix it?

I'm currently on a size small with a PD Aeria cockpit and not having any issues. I'm now pretty much 70.3 or 140.6 only and my current bike/fit is comfortable, allows me to turn out quality times and run well off the bike. I'm asking my fitter and Dimond these same questions so any thoughts are helpful for me to evaluate and know what I need to consider or be aware of down the road trade-off's I'm making.

I'm going to be using a Vision Metron TFA cockpit on the new bike, I'd imagine its 'easier' to start small and then adjust a size 'larger' within the cockpit than the other way around. But I'm really not into my fit other than, it works, i'm happy, dont mess with it.... thus I'm asking people who might know better and have better information.

I've attached the Dimond sizing chart, my 'optimized' fit at my last Retul fitting, images from the fit and a race image if that helps. Yes, I need to get my head out of the wind.

I'm not looking at any other bikes and I get an amazing deal on the Vision bar so financially it makes very, very little sense to look elsewhere

Thanks in advance!

Edit: Fit Video here https://vimeo.com/459704141

________________________________________________________
Taylor Rogers

2024: IM Hamburg
Last edited by: xcrogers: Sep 19, 20 8:18
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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I'm not a fitter but like many have more than a passing interest at looking at other peoples fits, so this is just my personal opinion!

There is a difference between the studio photo and the race photo in where your elbows rest on the pads, with them being further forwards in the race picture. This to me would indicate that you naturally prefer this extra reach for comfort. It looks like a solid fit and as you say if it's not broke don't fix it. This extra reach also helps get your head a bit lower, imagining where your helmet would be in the studio picture. I think you could develop to go a bit further forwards and maybe 1-2cm lower, and add some decent upwards tilt which would help lower your head, but you might need to look at another helmet to ease looking up.

If you go a size larger I think you might struggle to achieve this with the metron TFA as it has quite a high minimum stack height compared to the PD.

I reckon you are probably a similar height to me and are a classic top end of one size bottom of another, but committing to the vision bar likely limits your choice of frame size to the small.
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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If that were my fit I'd size up.
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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I can’t tell from the photos how much additional adjustment you could get in terms of stem length and saddle setback, but everything I would suggest to make you faster would require a longer position. If you are close to maxed out on stem length and saddle setback, and your saddle nose to crank spindle is good for you now, I would definitely consider the larger frame. I would guess that you could me much faster and more comfortable by bringing the hand up and head down.

No offense to your current fitter, but I bet Jim at ERO would have a field day with your current position and new bike day is a perfect opportunity for improvement. I wouldn’t spend a nickel until you had a more aero position dialed in. There are a bucket load of free watts being left on the table.
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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If you post a video of you riding on a trainer, there are a bunch of people who could offer advice on how to be in a better position.
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Re: Bike Upgrade, Change Size? [jimatbeyond] [ In reply to ]
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Thanks for all the feedback thus far.

Here is a link to the video of my most recent fit: https://vimeo.com/459704141

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Drop the saddle 15 mm, drop the cockpit 10 mm, move the pads and extensions forward 30-40 mm. And then post another video.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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I’ll need to cut down my seat post as I’m bottomed out right now so I’ll do that tomorrow in my shop and get the bike set up and post some video.

Your suggestions imply a larger frame isn’t the right direction?

Thanks!

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Frames grow in two dimensions, so it's tricky. I wish this bike was a bit longer, and I don't want it to get any taller.

Let's first get you in a good position on this bike, then you can take those measurements and shop with confidence.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
Last edited by: trentnix: Sep 20, 20 11:12
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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So its great you asked me to do this, found out my compression plug had failed as I was unpacking my bike, so good to know that before a race-day set up.

However, I dont think I can make all the modifications you're suggesting:

- seat drop - Can do, will cut down in shop
- drop entire cockpit - can do, I have space to drop the whole thing (FYI would be essentially slamming it to the frame, see picture)
- move pads and extensions forward - cant do, I could only move the extensions forward 20mm and the pads are already as far forward as possible. Could be resolved with new/aftermarket pads?

I can make the couple modifcations possible but figured I should at least make you aware of the limitations i'm at with my current set-up.

Thanks!

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Move the extensions forward 20 mm and make the other changes. Then we'll take a look.

We may be able to pull the saddle aft a bit, but you may need to find a cheap, longer -17 stem if that doesn't do the trick.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Longer stem.
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Updated video here: https://vimeo.com/460308177

as suggested:
dropped the entire front end 10mm
moved extensions out to max (about 15-20mm)
dropped seat 15mm

My first impression of this was that I felt my left leg/kneed kicking out to the left and my right leg/knee kicking out to the left. I didnt feel like I was using the entire pedal stroke. Not sure if thats a reasonable 'feel' or thats better/how it should be but thought I'd pass along.

Thanks again for thoughts/feedback!

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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That's better.

Bring the left cleat medially as far as it will go (without affecting whatever the fore-aft is) and see if that helps with the left knee. I'd have to see a front view and a rear-view to determine what's going on with the things happening in the transverse plane.

Angle the pads/extensions up a few degrees and also see if you can make another video where you push your chest forward (toward the floor) a bit, relax, and look forward. When you're staring at the floor you arc your back and roll your pelvis the wrong way.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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By angle the pads/extensions do you mean rotate the entire cockpit at the stem? Or do you mean angle up with with shims below the pads/extensions? Obvously easier/quicker to rotate the cockpit but I could model and 3D print specific some shims if thats better....

Thanks, this is all great (and a great learning curve), really appreciated! I'll give that stuff a try tomorrow evening and re-shoot a side/front video. A whole new aspect of triathlon for me to get lost in, wife will be overjoyed.

In terms of the bike sizing or updated cockpit does any of the updated information/video you've seen give a steer towards if I should remain at the current (small) size frame or move to a medium?

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Rotate at the stem. Once again, bike size is more complicated. Let’s get this right first.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Made the modifications on moving the cleat position (left leg felt better/straighter) and angled up the bars about 5 degrees.

Run 1: https://vimeo.com/460705682

Run 2 (focused a bit on your thought about chest positioning, while likely not successful immediately I could see how that would improve my neck/back/hips position): https://vimeo.com/460706412

Thanks for any additional feedback... also having some fun with 3d printing angled shims now....

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Pull the saddle back about 5 mm. Really wish that stem was 10 or 20 mm longer.

On the angled shims, I wouldn't want to trust me spinal integrity to something I 3d printed. And I don't think they really buy you anything.

Can you drop the cockpit any more? I'd like it to come down another 5-10 mm.

Also, get rid of those S-bends and get some ski bends or some of the 51 Speedshop extensions. I think that would help.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Looks like I could pull the seat back 5-10mm before I'm at the end of the rails, I could drop the cockpit 10mm (max) before the stem is 100% slammed. I'll give those a go tomorrow evening.

bars are something I could look at on their own. Is that for hand position alone or another reason?

at the cost of nice extensions (ie speedshop 51) I'm already well into the overall costs for the Metron TFA system which seems to have greater overall flexibility (ie angle) as well ships with S bend extensions (offering 245-385 extension adjustment vs my current extensions at 200-300). Though the new TFE extensions look sweet... I could purchase without the integrated stem (stock 90mm stem length) for a longer stem though the pads have far greater range than my current setup and could account for that stem length plus the entension you are suggeting (or so the fit guides indicate).

In terms of angle of the cockpit, I'd agree that if the change I've made is enough then I dont 'need' to print things. I'm using the model shop at my office for fun so I can controll the quality to a very high level. We also have the carbon/nylon filament (same stuff a number of well known shops that sell angled shims use). So its really more of idle fun with Rhino and printing things.

Thanks again for the thoughts, its been really helpful and informative.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Then instead of pulling the saddle back, it's time to bit the bullet and get a longer stem (2 cm longer). Keep the bars at the same angle, move the saddle forward (instead of back) 1 cm, and raise the saddle just a few mm.

I don't know what the current Metrons look like. I just don't like S-bends and you look like you are torquing your wrist a bit to grab the ends of the extensions. Just looking for better hand position. You're close.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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So a 120mm stem (Tri rig is 100), seams reasonable enough, I do a bit of research into options, trying to keep the front end as neat as possible.

In the second video, was I close/emulating what you were suggesting with regard to my chest position?


This is the FSA/Vision system in question: https://shop.visiontechusa.com/...ial-track/metron-tfa





TFE extensions (if I splurged)



________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Why don't you just get the TriRig Alpha One bar?
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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The TFAs look fine.

If you got a new bike that had a 20 mm longer reach, that would cover the stem change. But once again, we're not at the new bike part, we're trying to nail this position. It may end up saving you a lot of money and headache.

I recommend you change the stem on this bike - just get something cheap with a -17 pitch.

If you had a good fitter close with a fit bike, they'd be able to make these changes and dial you in after only a few moments. Those fit bikes are handy.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [jimatbeyond] [ In reply to ]
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The tririg system is great but I get what amounts to about a $400 savings delta on the vision system compared to tririg.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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I have a fit lined up locally early next week and will be using the help you’ve given me here as primer for that session. we’ll start with fit numbers in this area but the session is me on a jig so one step ahead there!

I’ve also got some 1:1 time lined up with someone recommended by my coach for additional discussion, education and possible fit/kit changes. So this is all serving to help me understand what my fit wants to be, questions to ask and goals for the session and the take some numbers away for new kit.

I’ll start looking for a cheap 120mm -17 stem

Thanks!

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Look forward to hearing the feedback of your people. Get pictures and video of your result on the fit bike and post it. If your fitter fights it, run away.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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xcrogers wrote:
I have a fit lined up locally early next week and will be using the help you’ve given me here as primer for that session. we’ll start with fit numbers in this area but the session is me on a jig so one step ahead there!

I’ve also got some 1:1 time lined up with someone recommended by my coach for additional discussion, education and possible fit/kit changes. So this is all serving to help me understand what my fit wants to be, questions to ask and goals for the session and the take some numbers away for new kit.

I’ll start looking for a cheap 120mm -17 stem

Thanks!


I have a bad feeling that your fitter has about 10% of the knowledge that trentnix has about fitting.
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Re: Bike Upgrade, Change Size? [jimatbeyond] [ In reply to ]
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Thanks, this is a helpful comment.

I had never heard of Trentnix before this thread but he's helpfully chimed in and I've gotten really great information which I'm going take forward. My conversations with my (new to me) fitter have left me with a good feeling in terms of mutual understanding of my goals, an appreciate of 'where i am' but also a lets get you on a jig and see what develops. I'll let you know how it goes on Tuesday.

I'll have my bike, old fit numbers, the input from this thread, and other professional input I'm soliciting which I would imagine is the best anyone can do. So I'm not really sure what you're suggesting? Shall I book a ticket to Texas from London for a fit? I'm not discounting anything Trentnix has said and implemented every change suggested (with positive results) so I have no reason not to take that foward and to challenge any differeing adivce I might receive down the road as a better informed customer.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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I would keep posting videos here and listening to what trentnix has to say.
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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I took a bit of time today to create videos of the following based on comments here (and some others I've had by people i've spoke with)

Run 1: New Stem (120mm, 17 degrees) - https://vimeo.com/462181686

Run 2: Seat up 5mm, forward 10mm - https://vimeo.com/462182931

Run 3: Pads forward 20mm - https://vimeo.com/462183649

Run 4: Pads forward another 20mm (now max forward) - https://vimeo.com/462184146

Run 5: All above plus helmet - https://vimeo.com/462184734

Compilation of all five runs (truncated time): https://vimeo.com/462199632

Things I noticed as I was moving through this, felt 'better' the longer/more forward I got, though my elbows, arms seem to float a bit. Maybe this would be helped by tighter/rounder/molded pads (and/or something a bit longer down my arm). I also outgrow my extensions and something with a bend seems to be more comfortable.

I tried to get video of side and front and lined up timewise (hopefully this is helpful). I'm finding this, plus the conversations I'm having offline with people really informative.

Thank you!! - T

Edit: Added Compilation Video

________________________________________________________
Taylor Rogers

2024: IM Hamburg
Last edited by: xcrogers: Sep 26, 20 12:16
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Pads back 1 cm and saddle forward 1 cm.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Room to move the saddle forward, so no issues there.


Regarding the pads, apologies it would appear the previous 20mm notes were wrong should have stated 15mm. So I could move my pads back 15mm (see attached picture).

I'll make those changes and test tomorrow.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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That’s fine. 15 mm back.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Modifcations made, video here:

https://vimeo.com/462323191









________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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How does that one feel?

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Apologies, not sure why my comments didnt go through on that.

Position felt generally similar to the last run. While I can feel a difference in the overall progression (which is for the better), its hard to pick out the individual small changes. I'd say the hands felt like they werent over shooting the extensions (as much) but still didnt quite 'know what to do with them'.

I'm now much more aware that I'm not sure about where my eblows should rest on the pads, but that might have more to do with having wide/flat pads versus a set that cup/lock my arms in better. Maybe with a back so I'm not tempted to shift around so much? It would also seem a set of extensions that allow my hands to sit a bit more naturally (ie bends of some kind) may also reduce the 'fidgeting' and keep me in position?

________________________________________________________
Taylor Rogers

2024: IM Hamburg
Last edited by: xcrogers: Sep 27, 20 5:10
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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I do think different extensions, as we discussed, would be beneficial.

I think this position is an improvement, but I wouldn't fight additional changes. For example, you could pull the saddle back 15 mm (and drop it 5 mm to compensate) and pull the pads back 15 mm as well and it would probably be pretty decent. I think you could drop the cockpit a bit. I think you could stretch out just a bit more (if your cockpit supported maybe 5-10 mm more armpad reach) and probably be ok. I wouldn't be opposed to stretching out just a bit more (by bringing the saddle back, say, 5 mm or *maybe* 10 mm).

I still think your posture could improve. I would be interested to see if you move around when you ride outside or when you ride hard.

All of that said, I think you're on the target. Getting to the bullseye is going to take some trial and error and some discernment that probably requires a good fitter to make some tweaks in person.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Thank you. This has all been very, very helpful and I appreciate the time you've taken to review and offer advice.

Its good to know that I could alter my position a bit more but both in shifting around a bit as well as being a bit more optimized. Though, as you say, might involve a bit more than can be gleamed from static videos. I seem to be (currently) limited to 15mm pad moves (or using an alternate stem to lengthen the entire cockpit) and have about 10mm more drop before totally slammed.

I'm also about 5-6 weeks post rib facture so my body is not 100% and might be some of the (current) posture issues though I know I do move around a bit during races. I can try and set up a video for a training session (I do all my riding indoors) which might mimic an effort a bit more, but getting some video outside/riding is a task here in London but its good to know that would be useful for a fitter moving forward.

In terms of the original question, you noted optimizing with my current setup before offering any input on a frame or cockpit, do you have any thoughts there?

I have my session on Tuesday so I'm looking forward to take this effort forward to that and see what numbers/information/discussion come of that. This thread and the other discussions I've had are giving me a lot to think about and consider.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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You should be able to measure the armpad stack and armpad reach and use that when bike shopping. You definitely don't want a bike with more stack than what you have now and probably could use a little more reach.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Your wrists do look uncomfortable holding on to the aeros. Maybe just rest your hands on top of the shifters.
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Re: Bike Upgrade, Change Size? [jimatbeyond] [ In reply to ]
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Yeah, more often than not my hands seem to migrate forward and 'hang' over the ends (see images). Its not the worst from a comfort standpoint but I'm reasonably sure from this conversation (and others) it isn't ideal for position or bike handling.

It doesnt inspire confidence if I need to shift my body and re-orient my hands for control versus my hands/orientation are already in a position to deal with an obstacle or wind.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Had my session earlier today and continued to learn a lot. It went well and used the position I ended up with here as a starting point for seeing what worked and what didnt. Ultimately the 'end' position had the seat a few mm lower and the pads a few mm back from current. The pads set a bit wider and something that cupped my arms better. The bars swapped for something with a bend and set at more of an angle. All of which we found it allowed me to get my head a bit lower.

Also we looked at the mechanics of how I ride in the position we played with crank length, insoles and cleat position and and some insoles. Along with modifying various bits here and there I was the most stable and fluid with 165 cranks so I've got something to think about there.

I've got quite a bit to go through and unpack from our conversation so I'll post a better de-brief later but I wanted to again say thank you for everyone's advise and giving me information and things to consider before going into the session. It made my time wildly more productive and allowed Wei to focus on the important bits.

Thanks!

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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What saddle are you on, there?

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Fizik mistica (my saddle) we didn’t swap for any others.

Why?

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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It's hard to tell because the angle of the picture on the fit bike is different from your last fit video. You look like you are sitting further behind the bottom bracket than before. The position on the fit bike looks closer to your original position from those outdoor photos you posted.

Once again, the angle (and nature of being knee flexed instead of extended) could be playing tricks on my eyes.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Ah. I’ll post some more images/video from the session and more info later. Big picture we started with my bike as positioned at last call per suggestions on this thread. Those dimensions we’re then used as the baseline for the bio bike jig and we played with the various positions from there. Taking something till no good and then pulling back and seeing how it all came together.

It’s the session showed I definitely don’t want to up size the bike and I could likely continue to adapt try to push the evolution a bit more as I get more used to riding in the position on the road. Assuming a cockpit can get the length and the angle it’s nothing ‘special’ . The one interesting bit (something that’s just been the status quo for well... ever) is the point that I want shorter cranks 165, down from 172.5. Maybe obvious but I never knew....

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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Following up on this, the session went well, we set up my 'existing' bike on the trainer and took measurements which were then translated to the jig. All of the changes were reviewed with an idea for aerodynmaics and biomechanics starting with review of seat and crank and then looking at the cockpit. We started with crank review (and a few seat position studies and then moved to the cockpit studies.

By and large the final changes are not far off where I am now (or at least accomplishable on my current sized frame). One of the more 'major' findings was that I benefit from reducing my crank length from 172.5 to 165 (in concert with a few other changes). Both in terms of efficiency and comfort on the bike as well as setting my body up for a good run afterwards.

I've continued to discuss all this with Wei who did my fit but as I gain so much from you/this thread I wanted to pass along for thoughts/observations.

Data/Measurements/Images gathered during the session below:

https://drive.google.com/...BDiuroJ7?usp=sharing
https://drive.google.com/...XkD4k-PY?usp=sharing

Assuming I stick with my size frame in the Dimond family do you see that the Vision Metron TFA or Trimax Carbon would allow me to achieve the position I'm looking for? Between the integrated hydration (1.5-2liters) I've designed with the other storage means I've got a BTA and maybe one BTS outisde the frame. and need to stop for a 70.3... and optimized for very little aid station interaction on a 140.6 with my exact nutrition. I realize I may be giving up an aero penalty compared to another bike but when you start to consider the other options I feel like I'll have a bike with more bottles or be more reliant on aid stations (either not the end of the world) and I'd like to stick with what I know and what I'm confident racing (in terms of strategy). Regarding crank length. I'm keen to not loose out on 'easy' decisions though that easy decision is not (necessarily) cheap. What could moving to a 165 crank be worth? Ie... how does it compare to say, finding a 'faster' bike or bike position where one might find 2-3 minutes on the bike. Not looking for exact number, just trying to gauge it.

I was then thinking i'd pair with:
https://shop.visiontechusa.com/...ial-track/metron-tfa

or the non- (fully)integrated version (i could use a stem to get the length as I think the effective stem length on the integrated version is 90mm)
https://shop.visiontechusa.com/...trimax-carbon-si-013

I'm not looking to rush out and buy a load of new gear, but looking to consider where or how I make the best moves. Ie does optimizing my cockpit and crank on my current bike versus buying a new bike with better integration or a 'faster' bike make more sense?

These are the questions I need to struggle a bit with but if you have an opinion I'd love to hear it.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Did you try a crank length shorter than 165mm?
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Re: Bike Upgrade, Change Size? [jimatbeyond] [ In reply to ]
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Yes, we pushed passed that length and the leg metrics started to go the opposite way so 165 was where we landed.

Why do you ask?

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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Many fitters don't know what they are doing and never go below 165mm because shorter cranks can be more difficult to source.
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Re: Bike Upgrade, Change Size? [trentnix] [ In reply to ]
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I'm still working through a load of possibilities (most likely totally over thinking this) but looking for your thoughts again. I'm discussing the same with the my fitter but always looking to make sure I've got some good checks and balances.

Baseline



measured to back of pad, using 85mm pads during test

- Looking at the Tririg fit it would seem the stack is no issue and towards the top of the reach (see attached PDF). I've inquired with them that if I use their scoops product (perhaps longer pad) if that might offer additional adjustments

As for vision

pad reach of 474 is easily accomplished with the Trimax and separate stem and then figure out my own way of making that set-up aero with the few cables that might present. fun with 3d printer, etc etc!!

OR

using the Metron integrated, math ensues...

the pad reach is 474 (to back of pad) (using a 85mm pad its 516.5 to center)
bike reach (405) + effective stem length (90) is 495. The vision chart shows center of base bar adjustment of -9mm (33.5 to center) all the way forward (ie 85mm/2= 42.5, then -9+42.5 = 33.5). 495 + 33.5 is 528.5mm which is in excess of 516.5 which would allow the position to work (and some room to spare)?



It would then seem both the tri-rig and vision would work. I could also look into using a 'longer' pad that might help with that situation as well.

The reason I am keen to push this is that I can obtain the vision bar at close to 60% of the cost of the tri-rig and retain an 'integrated' front end vs the trimax bar/stem. I'm just trying to make sure I'm looking at these numbers correctly and non misunderstanding my review of the parts.

________________________________________________________
Taylor Rogers

2024: IM Hamburg
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Re: Bike Upgrade, Change Size? [xcrogers] [ In reply to ]
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I apologize for not getting more into the details, but I'll just say if the math works, then it works.

Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)
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