[music] Mark Threlfall: Wow. What a lineup for today's
video? Now, you'd be forgiven for thinking that both bikes, behind me right now, are
more or less the same thing. They've both been designed with aerodynamics in mind. They've
both been designed to cheat the wind and to go fast. Well, not quite. Obviously, they
have both been designed to go fast, but they're technically different bikes.
On one side, I have a UCI legal time trial bike. On the other side, I have a triathlon
bike, and they have some significant differences. [music]
Mark: Now then, the fundamental difference between a time trial bike and a triathlon
bike is that a time travel bike has been designed within the UCI rules, professional cycling's
governing body. Now we've been really fortunate today to have actually been sent a UCI legal
time trial bike from Felt. It's the Felt DA. This one's come from UCI ProTeam rally based
in the US. The reason I know it's genuine is because it's even got one of the rider's
name tags on the top tube. Thank you very much, Magnus Sheffield. We
promise to hand this back in mint condition. Now I actually really like some of the wording
on the Felt website with regards to the DA. It says, "The DA represents not only our commitment
to aerodynamic efficiency and rider-fit optimization, but also to the collective ability of our
mad scientists to cleverly eke out every bit of speed under a uniquely specific set of
regulations." Well, it's that final bit that really hits
the nail on the head really. A time trial bike has to conform to those regulations set
out by the UCI, which admittedly, they are relaxing a little bit with time which is good
news. Certain elements such as the tube widths, the aero bar lengths, the saddle position,
all are closely monitored, which I do know some of that is there for safety, but [yawns]
it is a bit boring, isn't it? Speaker 1: Boring? It's not boring. This is
riveting stuff. Just to make sure you triathletes know you should be adhering to, well, I'm
going to talk you through the rules. The bike needs to comply to a triangular shape, a double
diamond frame, and also every tube needs to be able to fit into 8-centimeter boxes. In
addition, to comply with the rules, the nominal rear axle and bottom bracket axle need to
be located within side the down tube, chainstay, and seat tube boxes.
The triathlon bike, though, no chance. Mark: Wow, just a few rules then.
Speaker 1: Well, actually, no. I've got a few more from the rulebook. I'm not quite
finished. These are important. The extensions should not raise more than 10 centimeters
above the top of the elbow pads. This is known as the 10-centimeter Rule. The peak of your
saddle must be a minimum of 5 centimeters behind your bottom bracket. That's okay. Your
aero bars must extend no more than 75 centimeters in front of your bottom bracket, or 80 centimeters
if you're as tall as Conor Dunne. Mark: Thanks for the clarification on there
and, yes, really riveting stuff. [music]
Mark: Well, alternatively, the triathlon bike virtually has no rules to conform to, so the
designers really can go wild. They can really push the boat out in pursuit of that speed
and performance. There is, of course, comfort and practicality to take into account given
this bike is to get you around a triathlon, but in essence, the designers have free reign.
Assuming you are a triathlete watching this, then I think you picked the right sport.
Now, as an example, I have the Felt IA here. It's a dedicated triathlon bike. Well, yes,
the frame size is definitely in excess of 8 centimeters, and that is all to improve
its aerodynamics and the airflow attachment around the frame. You likely have seen other
brands with radical designs all in pursuit of that speed and aerodynamics, things like
missing down tubes, missing seat tubes, missing seat stays, beam bikes, full monocoque frames.
Arguably, they're quicker because they've been able to throw that rulebook out of the
window and deliver and design a bike that has the best numbers. At least that is the
theory. You've probably guessed it because, yes, I
am stood beside a race track here. I'm going to be doing a little versus: time trial versus
triathlon bike which is quickest? I'm here at Castle Combe Racing Track. It's a 2.977-kilometer
track. I'm going to be doing two laps on each bike so just shy of 6 kilometers. I'm going
to try and hold 300 watts for each run and simply see which one comes in fastest.
[music] Mark: Triathlon bike rolling start up to 300
watts. Let's go. [music]
Mark: 302 watts, pretty good. All right, here we go UCI TT bike up to 300 watts. Let's go.
[music] Mark: That felt fast. Time to see what the
results were. [music]
Mark: I know you're eager to hear the results, but first of all, I thought I'd actually just
talk to how it actually felt. Now, I have obviously been riding the Felt IA, the triathlon
bike for some time now, and I feel like I've set myself up on it pretty well. I've got
myself in a good aerodynamic fast position but also comfortable because, at the end of
the day, I'm trying to ride that bike for sustained periods of time.
That said, I don't feel like I've trade-off too much of that aerodynamics and speed for
that comfort. I feel like I've struck that balance pretty well.
The TT bike, however, well, this is the first time I have ever officially got myself and
set up into a UCI legal position. I've got to say it felt pretty odd and quite hard.
My gluts are hurting a bit now. I feel like I was contorted a little bit. At the same
time, my goodness, it felt so aggressive. I felt lower on the front end. I felt really
fast. The bike felt really rigid. I know it sounds odd; it just sounded fast. If I was
to make predictions based simply on feelings, I would say that bike was faster. It just
felt really good. The results are interesting because I went
8 minutes and 16 seconds on the triathlon bike, the Felt IA. Then I went 8 minutes and
20 seconds on the UCI legal TT bike. 4 seconds slower for the TT bike.
Now, that's really interesting, but, of course, it's not all simply about speed and aerodynamics,
at least it's not for the triathlon bike because, at the end of the day, that bike has got to
get us through a triathlon and run well off. Now, actually, looking at the triathlon bike,
the lack of rules within triathlon bike design and position can actually play into traffic's
favor from a functionality standpoint too not simply from a speed and aerodynamic standpoint.
See, a lot of triathletes prefer to have their saddle position slightly farther forward and
that has allowed them to open up the hips a bit more whilst they're riding rather than
being in a really cramped position, and that in turn can help with the run of the bike.
Actually, some brands make their seat tube angle on their triathlon bike slightly steeper
to help with this further and will quite often offer different seat posts with a slightly
more forward position, reversible seat post, or multipoint options on their seat post to
help you. Then, of course, there's the front end. Now
on TT bikes, they quite often have shorter head tubes and a slightly lower position which
will allow the rider to get into a more aggressive position, and I definitely felt that today.
I felt far lower on this bike and really, really aggressive. That's fine for short effort,
short TTs, but for 40k, 90k, 180k, those longer durations that we're typically doing in triathlons,
well, that's less suitable. For that reason, you tend to find
a little bit more adjustability on the front end of a triathlon bike, and quite often,
the option to go even higher to gain that comfort for those long durations.
Wow. There we go. I hope you now know the difference between these two bikes.
The time trial bike is obviously designed, simply, to get a cyclist from A to B as fast
as possible, even if it does require a little bit of contorting to get yourself into position
sometimes. Whereas a triathlon bike is designed to get you through a triathlon well and to
run off the bike well, and as it seems, it can well be faster sometimes too.
I love the TT bikes. If you're someone that loves the look of a TT bike and really wants
one too, that's absolutely fine, particularly for the shorter events, but I would just advise
thinking carefully about the storage options if you are planning to race anything longer.
Wow. There we go. I hope you have enjoyed today's video. If so, please do give it a
thumbs up. Give it a like. Don't forget to give GTN a follow over on social media, and
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[00:11:02] [END OF AUDIO]