You don't need much money to buy speed!

maviczap wrote:

 I take it that your Canyon didn't have aero clipon Tri bars, if so that's where your big gains have come from, plus the disc rear wheel.

Having participated in TT's in the before and after Tri bar era, then we all found our times improved by significant amounts when we fitted Tri bars to our TT bikes.

I wasn't rich enough to buy a disc rear wheel, so in the 90s there were plastic wheel covers that you could buy to do the same as you've done. I still have a pair in my garage, but I was never brave enough to fit them as they were bright pink! They were held in place by zip ties.

Anything that covered the rear wheel also improved the aero dynamics.

If you don't have one, get an aero helmet, that's also worth a chunk of time, after this it's marginal gains.

I'm sure if I'd had a disc wheel and aero helmet I could have gone faster and beaten my pb, which on the night I was spinning out 52 X 12 on a 8 speed set up. But that was a perfect night and I was at the peak of fitness, the top guys were consistently fit throughout the season.

You've made the biggest gains through technology, the next big gains and maintaining them is through a structured training program. 

Lovely looking bike, I love TT bikes

No clip on bars on my Canyon - I was really surprised at how much difference aero bars make!

Thanks I have a thing for TT bikes too, I like the pureness of the bikes.

The Giant Trinity in Sunweb colours is my favourite at the moment

don simon wrote:

Would it be churlish to point out that the university education and cost of CAD and CFD software have somewhat upped the initial low cost of the project.

Mighty impressive and good to get a straight comparison, or as close as you can honestly get.

Please don't remind me about how much I spent during my few years at university  The real bummer is, one of my mates from uni (who lived just at the other end of the M48 bridge), has 3 times less debt than me due to the difference in Welsh student funding. A couple miles distance makes a £30k debt difference 

Fortunately, I don't pay the ANSYS and Solidworks licenses I've been using (nor the cost of the RP)!

don simon wrote:

Would it be churlish to point out that the university education and cost of CAD and CFD software have somewhat upped the initial low cost of the project.

Mighty impressive and good to get a straight comparison, or as close as you can honestly get.

Please don't remind me about how much I spent during my few years at university  The real bummer is, one of my mates from uni (who lived just at the other end of the M48 bridge), has 3 times less debt than me due to the difference in Welsh student funding. A couple miles distance makes a £30k debt difference 

Fortunately, I don't pay the ANSYS and Solidworks licenses I've been using (nor the cost of the RP)!

asdfqwerty wrote:

I reckon most of the time you saved was from the change in body position because you bought TT bars for the 'new' bike. Everything beyond that is marginal. Sure they all add up, but you're comparing apples to oranges.

Yep, I fully agree.

When comparing to my Canyon Ultimate Disc (with 47mm Mavic Cosmics and aero integrated bar/stem);

I think the aerobars made the most significant time reduction (please don't ask me to quantify this because I don't think I need to do any more CFD analysis ).

I suspect that the front trispoke performed better than my Mavic Cosmic disc brake front wheel.

I would assume the custom made rear disc cover offered little to no performance benefit over my Mavic Cosmic 47mm rear wheel.

Again, I assume the aero frameset and aero bars actually made a reasonably significant difference over my Canyon the aspect ratio (Width/Length) of the tubing and bars on my Canyon is more than twice that of the TT bike.

What fascinated me was, even as an aerospace engineer, I was surprised by just how great the drag reduction was. I think "The whole is very greater than the sum of its parts" is very applicable.

Paul__M wrote:

"R&D testing of bicycle wheels as well as developing bicycle component fairings"

sounds interesting, but I don't suppose you are at liberity to tell us any more?

I have an NDA so I can't be too specific, but I can say that I've been speaking to a couple industry insiders about bicycle manufacture as well as bicycle aerodynamics.

Basically I've been trying to work out how the heck bicycle manufacture companies come up with all their designs (as well as their drag reduction results), none of the manufacturers publishes any scientific/academic papers/journals about their research - so it could all be rubbish (I am certainly not saying it is though!).

Bicycle aerodynamics is in a range at which the flow transitions between laminar and turbulent and the flow isn't steady. If a design could be created that could control the airflow (particularly if it could stop vortex streets) the bicycle could be more aerodynamically efficient.

There has been extensive research into boundary layer development, boundary layer transition and flow separation within the aerospace field, there are lots of equations and methods that can be used to determine the performance of an aerofoil (see Karman-Polhausen method and Blasius's solution).

I'm applying these methods to bicycle design to come up with a (valid and verified) processes for designing more aerodynamic bicycles - with the view of starting to design aerodynamic components/fairings/tube profiles.

In theory, once you've figured out a few stupidly complex things, you could design a process whereby all you do is define the size of the component and roughly where it is on the bike and it could iterate to a really aerodynamically efficient design using a Design Of Experiments.

hawkinspeter wrote:

@Wellsprop - I wasn't expecting CAD, let alone CFD analysis. I was thinking more along the line of an old bit of plastic and scissors.

Very impressive work and don't listen to Cugel - it's fun to go faster whether that's technical competence or improved fitness.

 Yeah, I've had plenty of time on my hands since I've been running and analysing 50 CFD studies on various bicycle fairings/wheels - just something to do whilst I wait for each run to solve (which takes about an hour).

Cugel wrote:

You aren't beating your own PRs if the increase in speed is due soley to the technology "upgrades". This is something I never grasp about TT lads - are you "competing against yourself" or actually in a race with others after all (more like an arms race than a fair fight, since it all seems to hinge on the technology)? I know, really - it's the latter, innit.

You could ride a 1939 Rudge and improve your times .... by getting fitter. I thought that was the idea ... but perhaps I am old and confused about these modern things.  One suspects that TTing has become a buy-stuff fest like everything else these days.

Still, your buying has at least been relatively light on your wallet.

Cugel.

Beating a PR is beating a PR, however it's done... I'm only interested in TT as I want to compete against my own times - I'm not really bothered how I stack up against others.

One of the main draws to TT's for me is the technology and aerodynamics aspect, as an aerospace engineer (currently involved in aerodynamic evaluation) it interests me. I also like being able to design, analyse and manufacture fairings and components for testing/use on my TT bike. I'm currently looking into developing and optimising fairings (thick aerofoils) for use at low-medium Reynolds numbers, TTing is to me is an extension to this.

As for improving my fitness, I have a cycling coach (ex-continental racer), my weight has stabilised at 66kg and I'm getting gradual improvements in my FTP - so I'm not sure what else I can do.

Aerodynamics is everything when it comes to cycling - and, as you said, aerodynamics cost a lot.

https://www.youtube.com/watch?v=mfEGiYD7ECU

This guy here also inspired me to see what I could with a very small budget, the fun thing is, with a small budget, optimising absolutely everything becomes even more important to get the best out of myself and the bike, so it becomes a real challenge.

http://www.cyclingweekly.com/news/latest-news/how-a-bike-costing-1000-wo...

hawkinspeter wrote:

@Wellsprop - I wasn't expecting CAD, let alone CFD analysis. I was thinking more along the line of an old bit of plastic and scissors.

Very impressive work and don't listen to Cugel - it's fun to go faster whether that's technical competence or improved fitness.

I should also point out that I did originally try to laser cut the wheel covers, but the laser melted the plastic and it started to smoke/flame so I thought better of that!