My Very First Recumbent is a V20

[Frito Bandito]

Just got some silver 390mm Nitto flared bars installed on my V20, along with brifters. Next up is to chop a few inches off the bottom so they don't strike my knees in slow speed turns, and then to wrap them. I liked the bullhorns with the TT shifters, but they were 420mm, leaving my forearms hanging out in the breeze, and the grips weren't as ergonomic as I would have liked. So, while the brifters come with an aero penalty over the tiny TT shifters, my forearms now being in the wind shadow of my thighs should be a net gain.

Earlier it was mentioned that knees higher than the eyes at the top of the pedal stroke starts costing aerodynamic drag, so I checked today while fitting the new cockpit and the top of my knees are exactly at eye level and my BB is at seat level. It felt twitchy in the putt putt around the block, but it should be ironed out and good to go for the next ride.

 

[Don1]

Pix? Where are the pix?

 

[Frito Bandito]

Here ya go braddah. Gonna test it out today and will try to get a better pic of it.

 

[Frito Bandito]

Well, the bars feel great. I almost hurled and I have a new kink in my neck but it is all good. They are 390mm Nitto B135 bars and were too small in diameter to fit on my V20, but I got some spacers. I wound up hacking off about 5" and it was enough.

 

[DavidCH]

Well... interesting to see the numbers popping. The bars look a bit upright with the hoods. Let's see

 

[Frito Bandito]

Yeah, they are a bit upright. I might lean them forward for the next ride as long as it either (1) improves the elbow tuck or (2) feels more comfortable without making the elbows stick out more. The new bars are way more comfortable than my TT setup with the bullhorns and they will be on the bike for the foreseeable future. The only possible change would be a Di2 setup.

 

[Frito Bandito]

Found something weird in my last 2 rides. On Friday I rode for 3 hours and 42 minutes, 220w average power, 34.6kph average speed, on 35mm Sciroccos with tubed Schwalbe Marathons with sealant, 90psi.


Then I rode again today (Sunday). 90 minutes on 230w, 34.7kph with a disc wheel in back, Schwalbe Pro One Tubeless with sealant at 100psi. Front was the same 35mm Scirocco with a tubed Marathon with sealant.


I do have a 50mm deep wheel for the front that I will put on that should help a bit with speed. And to be honest, I am thinking to put the Marathons on both the 50mm front and disc rear. Could it be that the Marathons just match the surface better?

 

[Don1]

Drop psi to 80 on yet fast wheels......

 

[vosadrian]

Hey Frito,

Interesting data. You need to start analysing CdA since you are riding with a power meter (easiest is to pay the MyWindSock subscription). Then let it analyze the differences and give you a CdA which is what you really want to compare. It will account for difference in power and weather conditions including wind. Then both rides would have a CdA and you could assess which setup is quickest. I think that some power meters read higher than others, so don;t read too much into the actual CdA values... but for comparison of your setup (with same power meter) it would be really helpful. I saw a clear difference in CdA recently when I havde mad 2 changes to my setup. I am surprised how sensitive it seems to be.

I am finding that I get some variation in CdA results between different loops I ride. I think it is mostly down to road surface. The loop I do with the worse CdA consistently has more chip gravel road surface, and the faster loops have more smooth surface. But that is OK... I just compare results from the same loop. It seems to do a pretty good job of accounting for wind, as I can get similar CdA results in very different wind conditions on the same course.

Cheers!

 

[Frito Bandito]

Yeah, I think that really is the best way to go. In 1 way I just want to accept that there is a small difference and not worry about it. Just focus on training to get the legs better able to handle more. But that would be leaving out extra speed or distance that could make a significant difference in my performance.

 

[vosadrian]

I get the train hard and race easy thing..... but I figure if you just ride what is fast all the time, you get experience and technique and optimisation that you would not get if you rode something you are not going to use when you want the best performance. By riding my fast setup all the time, I am working out the best techniques (like how to hande deep wheels in wind and where to position my arms etc.), and making optimisations (to bike and position) that will mean I will faster when I need the performance. I mean you can purposely ride slower by making your bike slower and maybe you work harder? But if you have a power meter, just use the fast setup and use power and time to set your training goals... and you will just go faster/futher on the good gear. Of course that assumes your fast gear is practical for every day riding. That is why I got budget chinese wheels... so they cost not much more than training wheels but are as fast as race wheels. If I break them, the cost to repair is similar to training wheels.

CdA analysis is great for optimisation. The good thing is that you don't even have to ride differently. Just do you normal riding, and it gives you a CdA. It accounts quite well for changing conditions, so you can even compare a full send max attack ride with no wind to a cruisey wander on a windy day. You do get some variation... but not as much as I expected... particularly if you ride the same course mostly.

 

[Frito Bandito]

All good points braddah. Yeah, you are right. I was kind of thinking to take it easy on the 50mm Bullet front and the 80mm Bullet rear in anticipation for the event so they have a better chance of making it through it without failing. But as you wrote, optimizing them and my position by using them with mywindsock would be worth the effort.

With that said, I just found a HED tri-spoke drive wheel with aluminum brake tracks for ¥45,000. It's 19mm so it isnt as wide as I would like.

 

[vosadrian]

Trispoke sounds good. at 19mm I would not use it for general use... just for comfort reasons.... but as a race wheel!

My wheels are a compromise in some ways, but I don't think I lose much in performance. The 88mm is a bit of a handful in certain situations, but is managable in that situation and totally fine 95% of the time. I got 25mm wide wheels as I wanted the wheels to suit Conti GP5k-TL optimally. Narrower is probably more aero, but I was willing to compromise for the comfort and fast tyres. The tyres are the main point for me. They are very fast, but very durable for everyday use. I just wanted a wheel that would make the best use of those tyres. There may be quicker wheel setups.... but If I cover the rear wheel, I would have to be very close to an optimised setup. Maybe a proper full disc rear and tri spoke front with narrow wheels/tyres would be a little quicker, but I doubt I would be losing much.

A lot comes to tyres.... Pick the tyres you like best and then get a wheel to optimise their use.

The results you got above were strange. The expected faster setup seems to be slower. Maybe something about the covered rear wheel is not working right?

 

[Frito Bandito]

I wish I could get that Tri-spoke, but I really can't. I have 3 sets of wheels now and can't justify it.

I know it is spinning less, but like you said, I don't think that is enough drag to make it slower than the training setup. It has to be something else. The Flaming Eyeballs video shows that their Monokote is smoother. I think theirs only connects near the hub and near the rim. Mine connects also along the majority of the spokes as well instead of being smooth. It looks like sliced pizza, so I don't think I am getting the full aero benefits of it. That disrupted airflow might be equivalent of just running those wheels bare in most conditions. There were 2 sections during the last ride that it felt like the sail effect occurred, but just because I want them to be faster with the Monokote doesn't mean mine are. There are a few wrinkles around the rim section that I smoothed out as well as possible, but it might be something else.

Last night I fitted the 25mm Marathon on my 50mm wheel as well as the "Bean dip" donuts in the hopes I would be able to put the Monokote on and test it out today, but I ran out of time. I will likely run that today because it isn't very windy, but I am not sure just how hard I feel like pushing today just yet. Since I plan on a long ride I will use the 2.5L hydration pack as well. Too many variables to draw any conclusions.

I like your setup and hopefully the handful of watts you could save with a disc doesn't cost you much.

 

[vosadrian]

I think the monokote setup is not for me. It looks too fiddly and fragile for me. And I want the ability to remove/replace. So at the moment I will look towards the more rigid clip on covering like Dyma. When I get it I will do some testing to see if it helps or hinders CdA.

My current project is a custom tail box... well more of a customized version of the CB race case. I probably would have been happy with the race case.... but I am interested in learning a bit about carbin layup, and it will also cost me less and be customised to my needs which are for a bladder rather than bottles, and I prefer to make it water resistant so if I have some clothing inside it will not get wet. It will be smaller than the Brain box. Propbably similar to race case. Aiming for some aero benefit as I have designed it to be entirely within my wind shadow (where the brain box was not) and wide behind my shoulders and narrowing with my limited understanding of what might be aero. We will see. Hoping I can carry a bladder without an aero loss. If I make a gain.... bonus!! So that is the current project. Enclosed rear wheel after that!

 

[Frito Bandito]

I have never tried laying CF before, but would it be possible to use the Monokote as the mold and lay the CF over the top of it?

Can't wait to see what you come up with for the customized version of the CB Race Case.

I too have an idea for my V20. It's not this, but I am currently happy with the 2.5L bladder in the Deuter Road One bag. I actually used it today for my 130km ride. I put 1L of hydration and 400g of ice inside for the outbound leg (45km), then topped it off again with 1.6L of hydration and and another 400g of ice for the remaining 85km. I could feel some of the coolness on my chest and stomach. Sitting up isn't the most comfortable, but I can live with it.

 

[vosadrian]

I've never tried CF before either..... it could be a collosal failure!! Youtube videos make is look OK??

I doubt you could use monokote for the mould. You need something you can apply pressure against to saturate the cloth any work out the excess. I am using styrofoam shaped with a wire cutter and sanding. The good thing about styrofoam is you can just spray it with Acetone and it dissolves... so you can use it as a sacrificial mold after the resin is set.

Sounds like you have a good setup for hydration. My box I am making will fit a 1.5L bladder which is enough for 99% of my rides which are <3 hours. I normally start a ride well hydrated any drink about one 700mL bottle per hour starting near the first hour. On rides above 3 hours, I plan to have the box capable of taking 2 more bottles... and I can either stop to refill the bladder with the bottles... or drink straight from the bottles. 3 hour rides I want to be able to do without stopping for a drink... but over that, I don't mind a rest stop to move hydration into the bladder... or grab some additional water at a servo.

 

[Frito Bandito]

They make it look easy enough on Youtube for even me to do it. The idea I have, which is a pair of kidney bags that fit under the seat (either CF or a Water Proof material) that stretch far enough back to remove the need for a rear disc, or make the power loss so small that a rear disc wheel isn't needed. Like there are small plastic panels inside the Moosepack to keep the material rigid, this panel velcroed to the frame would be inside the double layer WP material.

It might be a bit long on the bottom, and doesn't show just how far forward it would be, but far enough to provide decent storage without sacrificing to much aero loss.

 

[vosadrian]

You are thinking similarly to me!

My idea is to make some carbon panels from the rear case to the bottom dropouts to cover the top half of the wheel. My case should be quite sturdy so it should be quite strong. Would just want to add something to feed the air smoothly behind the wheel. Here is a pic of my bars to mount the case onto:

 

[Frito Bandito]

That looks clean so far. I've been working on mine today between other stuff. Can't ride tomorrow or Friday (golf) so I might be able to get 1 side mocked up tomorrow.