Looks like one of those beam bikes that all the boomers are fond of. Did they post any data?

Wow, cool bike! Looks like the love child of a Zipp 2001 and a Shiv Tri. To hell with the UCI!

Love it.
Can't wait to see it in action.

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@christopher_borden •
Spinning Spoke • Dimond Bikes • Flo Cycling • Castelli Cycling

Dzxc- it says data will be coming soon. Can't wait to see how fast it is.

Is this the "It's coming" product?

---

Find out what it is in life that you don't do well, then don't
do that thing.

Looking forward to the data (with pedaling mannequin please)

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http://cds-0.blogspot.com

TJ Tollakson rides/develops that, right?

yep

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---------------------------------------
Fruit snacks are for winners

pretty cool. doesn't look like much room for seat post adjustability.

Nice :) Can't wait for a head-to-head with other uber-bikes... Good luck to him and his brand.

I'm guessing that the front end of the beam pivots????



Hugh

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Genetics load the gun, lifestyle pulls the trigger.

I am in the dark, what are the advantages of a beam bike?

Lower drag from not having a seat tube, and a more comfortable ride with a small amount of suspension. They were big in the 90's, but were banned by the UCI, and (I hope) are poised to make a recovery as more UCI illegal designs become popular.

careful there!

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Would be even better with the newer Cervelo fork on the front.

It's nice...and pricey. Just saw it at expo and was quoted about $5,800 for fram/fork set. Maybe I didn't hear correctly, though.

---

TEAMFIREFIGHTER.com
STRIVE Omni Sport.com
Get Busy Living - or - Get Busy Dying

Stack and reach?

The same price is on their website. For that much I would like an integrated front end.

They are really fast, aerodynamically. The UCI hates them.

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AndyF
bike geek

Why on earth would someone want that?

For $5,800, you'd think they could get a fork that matched the frame(?). Even the inexpensive open mould bikes do that!

I'm really surprised to see everyone liking it. I think the Falco bike blows it away. This one just looks strange to me. As if you took bunch of stuff or whatever you could find in your garage and put them together. Case in point, none matching paint/finish fork.

Yeah if you are after looks and not engineering, the Falco is better.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I actually like the looks of this one better...too many "hard edges" on the Falco IMHO...

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http://bikeblather.blogspot.com/

Reminds me of a concept car, looks nice but functionally it might fall short.

Surely I can't be the only one wondering why it doesn't come standard with nut cups instead of pads on the aerobars?

I agree, but I think that the paint scheme of the Falco makes it appear to have more hard edges than it actually does.

I saw it in person today at the IMAZ expo and I must say that I was pretty impressed. Personally I want a bike that is fast, what it looks like really doesn't matter to me and that really is in the eye of the beholder anyway - I think it looks pretty sharp. I've never ridden a beam bike, but I would be happy to give it a try. From everyone I have talked to these bikes can be super fast, and I think we saw that a little bit with the power numbers of TJ at Kona this year in comparison to his peers. Hopefully, ST will do a write-up on it soon so we can get some more details.

---

---

Save: $50 on Speed Hound Recovery Boots | $20 on Air Relax| $100 on Normatec| 15% on Most Absorbable Magnesium

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I just want to add that ... if the engineering makes the bike, then I have high expectations for the Dimond bike. I had the pleasure to work on a collaboration with David Morse while he was at Zipp. Anything David designs is going to have my interest!

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AndyF
bike geek

Yeah, looks like it has stiffness of a noodle. What if you're mashing up a climb or taking fast hairpins?

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____________________________________________

Then it would have less rolling resistence than a more rigid frame.

How does bouncing down onto the saddle of a traditional frame increase your power anyway?

And

Suspension is a plus in corners.


*I haven't ridden it. I have no clue how it rides.

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@christopher_borden •
Spinning Spoke • Dimond Bikes • Flo Cycling • Castelli Cycling

I personally hate the feeling of bobbing around when I rode a friend's softride. I'd take a rigid rear end any day

I also just walked by the expo and saw the bikes and TJ talking to folks. They look nice.

---

-Of course it's 'effing hard, it's IRONMAN!
Team ZOOT
ZOOT, QR, Garmin, HED Wheels, Zealios, FormSwim, Precision Hydration, Rudy Project

I must say, I don't love this design. The front end looks like the R&D team handed the project over to the mail boy. It looks incomplete. But what do I know!

It's odd that orders can be placed on the website but there's no geometry information yet. :O

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/Howie Nordström

OK any sag in the frame robs power - you're expending energy to flex the frame in addition to going forwards. The rolling resistance claim just simply isn't true. And the suspension part is kinda valid, maybe, except try having a noodly front end when you're descending even modest speeds like 30mph on sweeping corners. Not confidence-inspiring.

Felt did testing when developing the IA and said that having only chainstays didn't provide "adequate" or "satisfactory" stiffness even for everyday riding. Idk.

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____________________________________________

any data on the suspension robbing power or that suspension doesn't improve rolling resistance?

I've never ridden a beam bike, so how much I'd personally like it, I don't know. That said, I find the rolling resistance argument believable based on speed loss I've experienced on bad roads.

It could be that the aerodynamics and rolling resistance make up for any loss in pedaling efficiency from bounding(which I'm guessing is something that you adapt to slightly.)

Having played with the new Dimond bike, I can confirm that the beam on the Dimond doesn't have the stiff suspension insert that the later Zipp frames (the non-soft ride versions) have, it is a direct solid mount.


(Full disclosure, I'm friends with the Dimond Bikes guys and have volunteered some hours with them, but have no stake in the company)

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-----------------------------
Full disclosure: Zwift, former Zipp and SRAM Design Engineer

That font looks like Iron Maiden and Def Leppard collaborated on it.

I don't think that any flex robs power. Wasn't it Jim Papadopoulos ( contributor to "Bicycling Science" ) that mentioned that most flex just comes back and leads to extra chain being taken up by the chainring? In any case, there are many reasons why you wouldn't want too much stiffness. See this: http://cds-0.blogspot.ca/...h-to-rolling_20.html


I'd like to see that. Link?

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AndyF
bike geek

If you want to improve your pedal stroke, ride a beam bike for a while. There is almost nothing more effective.

As a former Rocketwing owner, I'm happy to see the return of beam bikes. They are fast, no question.

I like that front brake. What is it?

Looks like the TriRig Omega.

---

Alex Arman

Strava

Wow, imagine how fast TJ would be if he switched to a regular bike then! Oh wait . . .

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Dimond Bikes Superfan

Hi Andy,

I just want to add that the model used to calculate the power losses enforced contact between the wheel and the ground so in real world cases the dissipation could be maximized due to losses linked to the loss of contact and excessive bouncing of the rider. There are much more complex models in the last few posts

One might argue that these differences could vanish if we consider a non-irregular ground but we should remember that the effect of this is similar to the effect of the pulsating power/force output of the rider.

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http://cds-0.blogspot.com

In any case, very nice work, Epic-o ! I don't think many people have fully digested the importance of what you've been saying.

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AndyF
bike geek

The question is whether the amount is .0001 watts or 1 watt or 10 watts.

If it is in the sub watt region you might gain more than that back from less physiological stress due to vibration on many roads. I've sort-of measured that on super nasty chipseal at being in the 5-10w range, even on nice race tires at proper pressures.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Thanks for the kind words Andy

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http://cds-0.blogspot.com

"Felt experimented with removing the seat stays from the bike to reduce aerodynamic drag. While these models created measurably less resistance, they were insufficiently stiff for normal riding without modifying the frame in other ways that came with different negative consequences."

(italics mine). From http://triathlon.competitor.com/...veiled-felt-ia_82065

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____________________________________________

Ok, but this is different than saying that any flex robs power, right?

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AndyF
bike geek

I think there is a pretty massive difference between the two bikes and types of stiffness. In the case of Felt, we don't know what kind of stiffness they are talking about, bb or saddle, and we dont know what Felt found unacceptable. Was it tire rub, rider feedback, saddle movement, unachievable without going back to the drawing board and having too great a delay in release. The article is way too vague to support your proposition.

I vaguely remember an article comparing the power of pros at Kona, but I don't remember any specifics. Did that article compare TJ to his peers? Was he on this new model for Kona?

I'm having trouble finding any information through google or the search box, so if someone could post a link, I'd really appreciate it. Thanks.

It will be hard to tease out how fast his bike is from his power numbers and bike splits. He puts out big power so a fast bike split is expected on any reasonable bike, and his position is so unusual it is hard to know what is bike and what is HIM.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

If the bike is as good as they claim, and they've claimed to have been in the tunnel already, why release a new bike with no data?

In this day and age they have to know that people expect data to support big claims.

"Wind tunnel results from our recent test will be made available here in the next few days. "

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Just a few days too late. If the results are as good as they claim, I think they missed an opportunity and the launch could have made more impact. Instead, people's impressions of the bike are being driven by how pretty they think it is.

I don't understand your reasoning? Why is this a few days too late? People are talking about it now without data and will still be talking about it in a few days when they release the data. Kind of two bumps of publicity instead of one in my opinion.

TJ rode the old model at kona this year.

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---------------------------------------
Fruit snacks are for winners

Agreed but his power was considerably less than the other guys, enough to raise my own eye. If you look at enough pro power files, and understand the dynamics of Ironman racing at the front, I think you can tease out the fact that just maybe him on his bike has been highly optimized. The biggest dynamic in a race like that is you tend to not ride your own power, you ride the groups power, so when ones guys power is less it certainly catches my eye.

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Sorry for the late reply - I have been traveling and unpacking. Anyway, yes he had his power file posted at one point, but the specific workout has since been made private.

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---

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I think I have read most of these comments already... Although the subject line has been, Zipp, Softride, TitanFlex, etc...

With the new skin in the game it's time the to line 'em up in the wind tunnel. All the big guns, Specialized, Cervelo, Orbea, Trek... and the beam bikes too. Seems every brand claims "Fastest at Kona", but know one can back it up. I write this as my add banner clicks through the Cervelo P5 "Simply Faster" ads...

Faster than what? Put up or shut up.

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____________________________________________
I only believe what I read when I agree with it...

So I found this link comparing TJ to Trevor W from St George this year. http://www.slowtwitch.com/...ele_power__3596.html Basically same split with TW putting out 8 less watts. Sure it is an SRM vs a Powertap and there is some inflation in TJ's power, but the numbers are pretty damn similar. Both weigh about the same.

Then you have the fact that his 2013 file is no longer view able. Seems odd. What kind of power do you remember him putting out in Kona?

I want to see lots of files to draw any sort of conclusion not just two. In addition, the way you attack an Ironman is completely different from 70.3s, factor in the analysis and the way they spent their power as well. TJ may have been trying to spend bullets early in attempt to catch up the group. Did Trevor have the benefit of Seb pulling him along? Given TJs split my guess is he would have been leading the charge. Lastly, that is Trevor's home course, it is fair to say he has much experience which can really save some watts as well. Lastly, TJ was on a different bike at Kona than the one I saw him riding at IMCDA earlier this year. I didn't pay much attention to it at the time, but it was definitely different. I'm not sure why the file disappeared. Here is a location where the info is listed.

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---

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Thanks for the link. Interesting that his power is much lower than previous IM where his power files are available. 290 NP, 280 AP vs the 251 AP in the chart you linked to. Great that the bike appears to be really fast but man where did the watts go?

Remember, the majority of professionals don't care about time, sans a few special things, they care about place. TJ only has to ride as hard as the group rides, so if everyone in the group is riding 270 and that means 255 for TJ, then he is saving energy. Now maybe TJ can really ride 285 for Ironman on his own, but he has no motivation in Kona because he knows it is all about saving energy for the run so he rides well within in. There are many variables, but honestly seeing the powerfile peaked my interest about Dimond.

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---

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I understand what you are saying about with respect to racing in the pro field. But in this case it looks like TJ wasn't riding in the group, at least from what can be gleaned from the Kona scrolling blog. From what I have seen there is usually no one near him when they list the mens field. Which makes his speed and power all the more impressive I would guess.

Exactly, if he was riding on his own than that is pretty much even more impressive, however both times I saw him - on Kuakani and at the turn at Hawi he was with people. At Hawi I remember him with Crowie and Hoffman. Look back at the splits that would make sense that he may have been with them for most of the return leg home along with some others like Jacobs, Rapp, etc

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---

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TJ was not with me until very near the end ~90 miles. Approximately the same time that our group (Jacobs, Marsh, etc.) caught Crowie who was alone and in no man's land. I believe he came through with Rapp.

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http://www.benhoffmanracing.com

Good to know, thanks for the correction, it makes it sounds like the ride was that much more impressive if he and Rapp were the lone two bridging the gap. It was no fun out there in the headwind after Kawaihae.

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---

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Any way you slice it, that is a sexy machine.

I could never get a seatpost tall enough to fit me on that bike, or I would certainly be dreaming about it.

Aero results have just been posted. Have to send an email for the PDF. http://dimondbikes.com/...ke/testing-and-data/

Tick tock, waiting for data...

Pretty significant difference for the bike only test, but a little bit more mixed in for the bike+rider. Interesting that they had head down so dramatically. I feel that I have seen the guys from Cervelo claim that some of the huge drag saving on the P5 come from the seatpost-leg interaction which would not be so evident with the head tucked down like that. Would love to see what that bike could do with something like the Trek front end compared to the PD bar...

I received it and its interesting. The rider on shiv and p5 data really surprised me, I've never seen beam bike data so had no expectations.

The head down thing makes sense for consistency, but it seems like some sort of head rest coming up from the stem would allow for the same effect but with a higher head height.

Wow, very interesting idea. Could be some super simple rod+cup/pad which would remove tons of random variability and possible changes in head position due to fatigue.

Holy tunnel asymmetry and lack of repeatability, Batman! =8-O

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http://bikeblather.blogspot.com/

As a point of contrast, when Jordan went into the tunnel at Specialized, he was in there doing runs, in and out to make changes, etc. for a couple hours....and every time they repeated the baseline configuration (done periodically throughout the session) IIRC his CdA measured within .001-.002 m^2...which speaks to not only Jordan's position being "comfortable" and "locked in", but also the repeatability of the equipment.

Just sayin'...

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http://bikeblather.blogspot.com/

150gF between both runs of the Shiv Tri w/ rider...

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http://cds-0.blogspot.com

So true.

Different aerobars on each bike, and it doesn't seem like there is any reason that should be the case.

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---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

My gut feel is that the reason they didn't do/show +ive yaw values with rider on probably didn't really have much to do with trying to minimize "rider fatigue"...

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http://bikeblather.blogspot.com/

The sad thing is that all these comments and observations about the testing are taking away from the bike itself...I actually think it could be quite good...

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http://bikeblather.blogspot.com/

Yes, even with the shortcomings mentioned, to test that well against the P5/shiv is extremely promising, assuming no intentional or unintentional futzing occurred with the protocol.

I'd ride it =)

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Hi everyone,

Thank you for all the comments, we are extremely excited to finally show this bike. We just returned from the launch at IMAZ and are eager to offer some insight regarding the recent wind tunnel test. First and foremost, our goal with the data is to be as transparent as possible. It has been apparent for years that the customer base for triathlon and cycling is highly educated, insightful, and hungry for real data. We deeply understand that legitimacy and acceptance is impossible without being forward and open about methods used to obtain data. To that end, the entire testing protocol, an explanation for the protocol, and each data point is detailed in the wind tunnel report. The testing protocol was formed largely from experience over +100 hours of conducting wind tunnel tests at multiple tunnels while working as a design engineer for Zipp (and a few hours as a test dummy in the tunnel). The testing conducted on the Dimond frame marked our first time at the Faster wind tunnel, so we also relied on valuable input from the tunnel operators at Faster, who were gracious in sharing their insight.

We were surprised to see such stark asymmetry in the data between negative and positive yaw angles. Some asymmetry is expected from the drivetrain, but the data are the data. There are certainly some improvements to be made in honing in on the repeatability – especially with rider-on tests.

I saw quite a bit of discussion about saddle ‘suspension’ so I’d like to offer info here as well. We designed the top tube to be rigid. On a size medium frame there is 0.065mm of flex per kg on the saddle. For a 75kg person, the saddle would drop about 4-5mm if they put all of their weight on it. The sensation while riding feels quite smooth. The top tube is removable by a single bolt for packing and travel and there is no movement or adjustment at the joint.

As a new company we are always looking for constructive criticism and ways to improve. Your continued support and discussion is highly appreciated.

Kind regards,

---

David Morse

For fun:

Zipp 2001



Zipp 3001


Dimond

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

did the 3001 have a 700c front and 650 rear?
and why?

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@christopher_borden •
Spinning Spoke • Dimond Bikes • Flo Cycling • Castelli Cycling

no, just a wonky image, I've replaced it

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---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Is there any chance that the P5 and Shiv Tri in Figures 1/2 and 5/6 are mislabelled? Figures 1 and 2 (bike only) show significantly less drag for the P5 vs Shiv, whereas Figures 5 and 6 (bike with rider) show significantly less drag for the Shiv vs P5.

Why the different bars ? That could swamp a lot of any projected gains.

This is my favorite "iteration" of an old Zipp 2001...mostly because of the Felt bayonet fork on it :-)

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http://bikeblather.blogspot.com/

Or the p5-6 fork!

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Wrong headset size...bayonet is 1"...but, I might look at fitting a Felt bayonet on my old Alu P3 :-)

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http://bikeblather.blogspot.com/

Saw that also. Definitely a head scratcher and not consistent from what we have seen from data generated by TREK and Cervelo.

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---

Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

David (Dimond) - is the test available on your website or do we really have to write you an e-mail to get it? - Turq

Looks like there is enough room on the dimond for a p5 fork. Definitely room for a P3 or P4 fork. Those are supposed to be around .005 CdA better than the 3ttt

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---

Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

More like .002 CdA

http://www.cervelo.com/...odigious-father.html

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

You are right.

The 3t was about that over the Wolf and then the FK24 was that again.

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Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

Sure...but isn't it typically the case that the drag is higher when the wind is striking the DS of the bike first (IIRC)? That's the opposite of what's shown in the plots.

Also, the test protocol mentions a "wheel-only baseline" that was apparently done to +/-20 deg., but those results aren't shown. If that also shows some asymmetry (assuming a front wheel was tested) and in the same direction, that can give some clues as to what is going on.



The bike only runs appear (to my eye) to have a fairly significant amount of variability as well (i.e. >25g at certain points).

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http://bikeblather.blogspot.com/

It is my understanding that Faster has some pretty major issues when it comes of variability. IIRC Velonews tried to use the tunnel for some testing and couldn't get reliable numbers and then moved the testing to A2.

---

---

Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

Hi Heath,

You might be right. I heard Bicycling Magazine also had that issue.

Cheers,

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Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

That might be what I was thinking of. I know at least one magazine scrapped their tests at Faster and went to A2.

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---

Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

I took a quick look at the pictures of TJ on the bike with his head down. You'll notice that when he is on the Dimond, he's not as stretched out as he is on the other two bikes. This difference will change his back angle, the angle of his upper arm, and square his shoulders differently. This would give the P5 and the Shiv better results for the "rider on bike" data.

---

Mat Steinmetz

51-SPEEDSHOP.com - instagram - @matsteinmetz - facebook

What do you make of the bike with rider data? The Shiv is showing lower drag than the P5. The reverse was true for the bike without rider. I thought that Cervelo designed their bikes with the rider in mind. I can't help thinking that the graphs are mislabeled.

Your observation is warranted and I appreciate the concern. Between testing notes, the raw data labels, photos of each test run, and data time stamps corroborating the order of each run, I may assure you that the data corresponds correctly to the graph labels.

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David Morse

This is a good observation. I notice the list of fit parameters for each bike doesn't include any measurement of shifter position in the forwards/backwards direction, only the separation and forearm angle. If the rider always holds the shifters in the same way, it's really the reach to the shifters that determines the riding position rather than the pad reach, within reason.

I've got data from that tunnel with sd of 30g on bike only testing. Quickly scanning over it I don't see any yaw dependency.

Specialized Wind Tunnel update:

Bike alone std dev of 3 x 30 sec samples with wheels spinning is 0.0005 (m^2) at 50 kph. We can get better, but this is consistent data and I'm pretty confident of this precision and accuracy now. Bike and rider std dev of 2 x 60 secs (now, improved since Jordan was in the tunnel) is at 0.001 (m^2) at 50 kph. If the rider moves around a bunch, it'll be worse than this, but it seems pretty consistently tight w/r to repeats.

Congrats to the Dimond guys - awesome to see some new product out there and am impressed with all of the work on this front. The people on this forum know how hard it is to bring a new product like this to market. All the best.

Mark

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--
Mark Cote
MITAerobike
Specialized Bicycle Components

Sounds like you have it nicely tuned up and all ready for the "winter nerd camp"...now we just have to schedule it ;-)

Oh yeah, is the espresso machine installed in the control room yet? :-)

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http://bikeblather.blogspot.com/

Winter Nerd Camp! I want to go to there!

Dimond manufactured in heaven? No, it's Iowa...

http://m.desmoinesregister.com/...311260055&f=1200

Does anyone know if a beam/V frame bike is faster/slower than the 'Lotus-like' designs (Lotus type 108 (1 stay, 1 fork...Boardman's Olympic one), Lotus model 110 (2 rear stays and 2 forks...road version of 108), CAT Cheetah (most similar to Type 108 I guess), etc.)?

I recall (maybe cervelo data?) the post P3 era bikes are faster than all the pre UCI rule changes super bikes.
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bikemessengersrepresent

Cool numbers! Thanks for posting, Mark.

Even cooler that you quoted your results in units that make sense (m^2).

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AndyF
bike geek

The olympic lotus is hard to compare since it was a track bike. Maybe the T4 is faster.

The cat cheetah is not great supposedly.

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