Change the front end shape to mate with the front wheel. I would need a large chainring though.
Triathlon Forum
Login required to started new threads
Login required to post replies
Re: Beam Bikes - Dimond and Falco [chaparral]
[ In reply to ]
Change the front end shape to mate with the front wheel. I would need a large chainring though.
Re: Beam Bikes - Dimond and Falco [chaparral]
[ In reply to ]
Hi Chaparral,
The beam on the Dimond has about 5-7 millimeters of flex. As far as I am aware, a seatpost that is able to attain the same range of displacement does not exist outside of suspension seatposts, which are neither aerodynamic or competitively weighted. The beam design does offer a significant comfort advantage (which, I would argue, leads to a performance advantage over IM length races), though we were very particular to make sure that the natural frequency of a rider on the beam was much higher than typical pedaling rpms in order to avoid "pedal bob".
David Morse
The beam on the Dimond has about 5-7 millimeters of flex. As far as I am aware, a seatpost that is able to attain the same range of displacement does not exist outside of suspension seatposts, which are neither aerodynamic or competitively weighted. The beam design does offer a significant comfort advantage (which, I would argue, leads to a performance advantage over IM length races), though we were very particular to make sure that the natural frequency of a rider on the beam was much higher than typical pedaling rpms in order to avoid "pedal bob".
David Morse
Last edited by:
DimondTech: Oct 20, 14 15:29
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
Hello
You want to sponsor a Fat guy with no talent on his quest to reach kona in 5 years?
You want to sponsor a Fat guy with no talent on his quest to reach kona in 5 years?
Re: Beam Bikes - Dimond and Falco [jackmott]
[ In reply to ]
Hi Jack,
Exactly - an appropriate width clincher tire matched to an aero wheel actually makes a pretty good leading edge, especially at yaw. Furthermore, the added surface area of a seat tube contributes to overall drag caused by viscous shear. Any would-be gains made from fairing the tire with a seat tube would have to be weighed against the frictional losses caused by the added surface area.
Indeed, current traditional TT/Tri bikes have been undergoing constant refinement and optimization using very sophisticated engineering design tools over the past decade. I think it is a great testament to the aerodynamics of the beam design that the Dimond is able to compete with and out perform these highly optimized designs despite being in its first iteration.
David Morse
Exactly - an appropriate width clincher tire matched to an aero wheel actually makes a pretty good leading edge, especially at yaw. Furthermore, the added surface area of a seat tube contributes to overall drag caused by viscous shear. Any would-be gains made from fairing the tire with a seat tube would have to be weighed against the frictional losses caused by the added surface area.
Indeed, current traditional TT/Tri bikes have been undergoing constant refinement and optimization using very sophisticated engineering design tools over the past decade. I think it is a great testament to the aerodynamics of the beam design that the Dimond is able to compete with and out perform these highly optimized designs despite being in its first iteration.
David Morse
Re: Beam Bikes - Dimond and Falco [FTDA]
[ In reply to ]
GT Superbike, built for the 96 Olympics:
---------------------------
''Sweeney - you can both crush your AG *and* cruise in dead last!! đŸ˜‚ '' Murphy's Law
---------------------------
''Sweeney - you can both crush your AG *and* cruise in dead last!! đŸ˜‚ '' Murphy's Law
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
My BP Stealth has noticeable vertical flex/give, which is great, and quite a lot of side to side flex when climbing out of the saddle, which isn't quite so confidence inspiring.
I really recommend them. Although the geometry is road-based, you can get round that with a forward post, they're cheap, weird, turn heads, won't lose value, are really easy to build up, and seem to be fairly fast.
Picture is during the build.
Post build:
-------------------------------
´Get the most aero and light bike you can get. With the aero advantage you can be saving minutes and with the weight advantage you can be saving seconds. In a race against the clock both matter.´
BMANX
I really recommend them. Although the geometry is road-based, you can get round that with a forward post, they're cheap, weird, turn heads, won't lose value, are really easy to build up, and seem to be fairly fast.
Picture is during the build.
Post build:
-------------------------------
´Get the most aero and light bike you can get. With the aero advantage you can be saving minutes and with the weight advantage you can be saving seconds. In a race against the clock both matter.´
BMANX
Last edited by:
Barchettaman: Oct 20, 14 13:26
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
DimondTech wrote:
Indeed, current traditional TT/Tri bikes have been undergoing constant refinement and optimization using very sophisticated engineering design tools over the past decade. I think it is a great testament to the aerodynamics of the beam design that the Dimond is able to compete with and out perform these highly optimized designs despite being in its first iteration.
Hey David, you're too modest. Your Dimond reflects excellent execution of a beam bike. Plenty of other beam bikes have mucked up design and execution. You've corrected many historic issues, so while this is your first Dimond iteration, you've evolved cutting edge distinctions.
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
Keep the good work guys! I love what you are doing! I m a big believer in the beam bike concept.
Jonathan Caron / Professional Coach / ironman champions / age group world champions
Jonnyo Coaching
Instargram
Jonathan Caron / Professional Coach / ironman champions / age group world champions
Jonnyo Coaching
Instargram
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
DimondTech wrote:
Hi Chaparral, The beam on the Dimond has about 5-7 millimeters of flex. As far as I am aware, a seatpost that is able to attain the same range of displacement does not exist outside of suspension seatposts, which are neither aerodynamic or competitively weighted. The beam design does offer a significant comfort advantage (which, I would argue, leads to a performance advantage over IM length races), though we were very particular to make sure that the natural frequency of a rider on the beam was much higher than typical pedaling rpms in order to avoid "pedal bob".
I did not know it was that much flex, do you know how much the IA's elastomers deflect? The comfort factor is good, but I am still not convinced that seat tube (or even a vestigial seat tube) would not be even better. I mean the beam does not need to firmly connect to the seat tube. Maybe it could even be used to store spares.
Re: Beam Bikes - Dimond and Falco [chaparral]
[ In reply to ]
Re: Beam Bikes - Dimond and Falco [DimondTech]
[ In reply to ]
Is the Dimond bike OK to use on a standard skewer clamped trainer? There are other threads which claim it is not OK for trainer use.
Re: Beam Bikes - Dimond and Falco [FTDA]
[ In reply to ]
FTDA wrote:
Change the front end shape to mate with the front wheel. I would need a large chainring though.
Holy chainring!
Re: Beam Bikes - Dimond and Falco [Sweeney]
[ In reply to ]
Sweeney wrote:
GT Superbike, built for the 96 Olympics: Hello beautiful! I know the eye isn't a great wind tunnel but that bike looks FAST!
Re: Beam Bikes - Dimond and Falco [BryanD]
[ In reply to ]
Re-doing a softride tt7. Will post some pics after the build.
Re: Beam Bikes - Dimond and Falco [devashish_paul]
[ In reply to ]
I always wondered how fast this bike was, bought it in 2012 as frame only from a shop in Chiliwack. Brand new but from 1998…..Sitting in his shop for 14 years!!
Had to buy it last minute when I finally realized the P-5 wasn't coming that year, raced it in CDA and IMC. Not sure about aero…but Mike Burrows is a smart guy.
Maurice
Had to buy it last minute when I finally realized the P-5 wasn't coming that year, raced it in CDA and IMC. Not sure about aero…but Mike Burrows is a smart guy.
Maurice
Re: Beam Bikes - Dimond and Falco [chaparral]
[ In reply to ]
chaparral wrote:
I still do not know why they do not have a seat tube. The seat tube should help aero dynamics by creating a much better leading edge for the wheel than a tire. Even the part that does not shield the tire would create a bunch of lift of low yaw numbers, which is helpful. It made sense when the beam had some suspension in it, but both the Dimond and the Falco are rigid. I think they are making a comeback because they look really cool. The dimond is also pretty aero, but I think it would be even more aero with a seat tube.
I have to agree but for a different reason. If you look at both the P5 and the Speed Concept they maximize the size of the seat tube near where it meets the top tube (in Trek's case, they do this with the draft box). In Cervelo's white paper, the stated reason was to reattach airflow behind the rider sooner and therefore reduce pressure drag.
With that said I think Dimond is on to the right thing with rider comfort. IMO the next generation of UCI illegal superbikes will probably continue and improve upon current storage integration. The only aero improvement I see being made across the board is elimination of the seat stays in favor of larger chain stays ala the QR Illicito. Bikes that don't have integrated front brakes will likely move to straight pull brakes. Otherwise the focus will be on comfort, likely with some sort of dampening built into the seat post similar to 3T's mounting mechanism.
Re: Beam Bikes - Dimond and Falco [jonnyo]
[ In reply to ]
Re: Beam Bikes - Dimond and Falco [GreenPlease]
[ In reply to ]
GreenPlease wrote:
chaparral wrote:
I still do not know why they do not have a seat tube. The seat tube should help aero dynamics by creating a much better leading edge for the wheel than a tire. Even the part that does not shield the tire would create a bunch of lift of low yaw numbers, which is helpful. It made sense when the beam had some suspension in it, but both the Dimond and the Falco are rigid. I think they are making a comeback because they look really cool. The dimond is also pretty aero, but I think it would be even more aero with a seat tube.
I have to agree but for a different reason. If you look at both the P5 and the Speed Concept they maximize the size of the seat tube near where it meets the top tube (in Trek's case, they do this with the draft box). In Cervelo's white paper, the stated reason was to reattach airflow behind the rider sooner and therefore reduce pressure drag.
With that said I think Dimond is on to the right thing with rider comfort. IMO the next generation of UCI illegal superbikes will probably continue and improve upon current storage integration. The only aero improvement I see being made across the board is elimination of the seat stays in favor of larger chain stays ala the QR Illicito. Bikes that don't have integrated front brakes will likely move to straight pull brakes. Otherwise the focus will be on comfort, likely with some sort of dampening built into the seat post similar to 3T's mounting mechanism.
Like this?? Plus or minus disk brakes:
Culprit Legend
Re: Beam Bikes - Dimond and Falco [GatorRacer]
[ In reply to ]
The Culprit Legend is still a work in progress and will make it to market next year is the plan. Keep your eyes out for the bike launch again. yes, it will have disc brake option as I believe it takes brands like Culprit to start developing the bikes for the brake makers to jump in. But the bike can also run rim brakes.
Re: Beam Bikes - Dimond and Falco [culpritbicycles]
[ In reply to ]
Get ride of seat stays = less drag
Disc brakes = more drag
So what's the point?
Disc brakes = more drag
So what's the point?
Re: Beam Bikes - Dimond and Falco [KJGrog]
[ In reply to ]
you painted it???? enjoy the ride!!!!
Jonathan Caron / Professional Coach / ironman champions / age group world champions
Jonnyo Coaching
Instargram
Jonathan Caron / Professional Coach / ironman champions / age group world champions
Jonnyo Coaching
Instargram
Re: Beam Bikes - Dimond and Falco [Grill]
[ In reply to ]
Yes, no seatstays reduces drag, Disc brakes add some drag. However, you choose your option. The beauty of my design is you can have either rim brakes or disc brakes on the same frame. Such as our Croz blade bike. In a race course like Challenge Phuket where you have about 20 km of very technical riding with hay bails out on the turns and often wet rainy conditions. disc brakes have an advantage. on a flat course. go rim brakes. Best of both worlds. With the new shimano flat mount design, disc brake mounts wont come at much an aero dis advantage anymore.
I live in Taiwan full time, it rains in Asia alot. disc brakes on my Croz Blade are something I ride and have no desire to go back to rim brakes personally. The biggest issue with disc brakes are those who have never experienced them on a road bike at speed. Go try the new Shimano ST-785 or ST-685 and they are a game changer. Imagine that kind of control and performance gains on technical courses.
Point here is this, If its a flat course, of course, run rim brakes for a faster build. The bike will have that option. If you are riding a course where confidence and ability to descend at higher speeds with more control gives you an advantage, then disc on that course has its advantages. The frame does not force a rider into rim or disc. It only opens the options to the rider.
Bikes are also about being different and unique. Culprit bikes are all painted to order and this future model and Croz blade lets the buyer have a bike that has more build options and that is something we are proud to offer, versatility. The new design will also be very fast as I am working with a very capable CFD expert in developing the re designed frame.
Bikes are all about the buyers choice. Having a bike with disc brakes is different and some people want that unique bike as well as confidence in the bike increases ones athletic ability.
I live in Taiwan full time, it rains in Asia alot. disc brakes on my Croz Blade are something I ride and have no desire to go back to rim brakes personally. The biggest issue with disc brakes are those who have never experienced them on a road bike at speed. Go try the new Shimano ST-785 or ST-685 and they are a game changer. Imagine that kind of control and performance gains on technical courses.
Point here is this, If its a flat course, of course, run rim brakes for a faster build. The bike will have that option. If you are riding a course where confidence and ability to descend at higher speeds with more control gives you an advantage, then disc on that course has its advantages. The frame does not force a rider into rim or disc. It only opens the options to the rider.
Bikes are also about being different and unique. Culprit bikes are all painted to order and this future model and Croz blade lets the buyer have a bike that has more build options and that is something we are proud to offer, versatility. The new design will also be very fast as I am working with a very capable CFD expert in developing the re designed frame.
Bikes are all about the buyers choice. Having a bike with disc brakes is different and some people want that unique bike as well as confidence in the bike increases ones athletic ability.
Re: Beam Bikes - Dimond and Falco [Grill]
[ In reply to ]
Grill wrote:
Get ride of seat stays = less drag Disc brakes = more drag
So what's the point?
Not to speak for them, but I think the "point" is innovation, somebody has to be first to try new things so that technology can improve. Like say without Mavic Zap (which was miserable) we might not have Di2. Or without Zipp/Softride we wouldn't have Dimond/Falco, etc.
My Blog - http://leegoocrap.blogspot.com
Last edited by:
leegoocrap: Oct 23, 14 8:27
Re: Beam Bikes - Dimond and Falco [leegoocrap]
[ In reply to ]
leegoocrap wrote:
Not to speak for them, but I think the "point" is innovationIt is just frustrating when the better solution is clearly to just use a rim with a better material for braking, which is avoided because it adds weight, so instead they add disc brakes, which also add weight, and drag.
It is just total madness
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
jackmott wrote:
leegoocrap wrote:
Not to speak for them, but I think the "point" is innovation
It is just frustrating when the better solution is clearly to just use a rim with a better material for braking, which is avoided because it adds weight, so instead they add disc brakes, which also add weight, and drag.
It is just total madness
well... some innovation does end with a closed door. :D
Personally I think rim braking is beyond adequate on 99.9% of the roads a triathlete will ever face (and most road riders too) but if somebody found a way to get the caliper integrated then sure, maybe in 10 years we're all riding disc Discs!
My Blog - http://leegoocrap.blogspot.com