My Very First Recumbent is a V20

[Frito Bandito]

Not quite what I was hoping for, which was an enclosed fairing that I could store stuff in. Overcoming the curvature of the seat by using panels just results in a pretty trashy looking fairing with my skill level. Maybe with styrofoam or something similar I can shape with sanding blocks or a grinder could be done to give me a mold that I can lay up in carbon fiber. But for now, there are just two panels velcroed on.

 

[Don1]

If it works....

 

[Frito Bandito]

At least it can be taken off easily haha.

 

[vosadrian]

I think down there, you want it as narrow and close to the frame as possible for aero. You want to stop the air from getting into the fram and wheels, but not create more frontal area by making it wide. It seems the best place for storage is behind your shoulders where it does not add to frontal area and may even reduce Cd by reducing turbulance. So I think what you have should help with aero if it is close to the frame (difficult to see in photo). If you want storage, I think the best is the tried and proven storage location!

I have the moose pack in the frame. I do plan to experiment with fairing the rear dropouts... see if MyWindSock can detect and improvement.

 

[Frito Bandito]

Those two pieces sit pretty flush up against the frame without flaring outwards. On the left side I might punch a hole for the rear brake cable to pass through, or just make a slit long enough for the fairing to install or remove by allowing the whole brake cable to poke through. The combination of the fairing and disc wheel with a tubeless Pro One is certainly faster though. It was tough for me to hold 34.5kph for any considerable length of time with the Sciroccos and Marathons on weekday rides when the bike path is empty and there are no gates to slow down for. While I only averaged 34.4kph for today's ride, a significant portion of that was slowing down for the gates, stopping because someone hit my rear wheel with a frisbee, coasting, and taking it easy because of a hangover. IOW, that was the easiest 34.4kph ride I've ever done. Without the fairings it still would have been fast just with the disc wheel. Now I need to either put the 5omm front or upgrade to an 80mm deep wheel.

 

[Don1]

test one at a time..... come on.

 

[Frito Bandito]

I will have to get the paid subscription for MyWindSock so I can get a better idea of where the speed is coming from.

 

[vosadrian]

Nice one!

Yeah, MyWindSock is only About US$15 a year. I figured it was nothing for the convenience compared to other CdA tools. It would account for different riding conditions and you could compare easy days to hard days. It detects when you use brakes and removes that from the calculation.

I have something similar planned for mine eventually... but one thing at a time for me. I'm still wheel testing and working on the next thing which is the talk box. Current testing says the wheels are about 0.02 CdA better than the Roval 50mm. They were quite a bit better than the stock wheels also.

 

[Frito Bandito]

I am a tech dinosaur and probably wouldn't use it to its full potential but $15/month is cheap. Making a tail box sounds fun. I can't do the vacuum bag method for sure, but might be able to whip up something to fill in that gap in the near future.

 

[vosadrian]

I'm going to try to do the vacuum bagging with a clothes storage bag and an old Dyson. Apparently you can get enough vacuum to make it worthwhile. It could all turn out to be a massive failure though. We shall see. I am going to do a small prototype before doing the real thing to see what happens.

 

[Frito Bandito]

Since yours will have the hydration inside it will make sense for it to be stronger. It can't be too hard though. A shop near me is closing at the end of this month and they have only 1 sheet of CF material for about $40. Not sure if it is enough for what I want to do, and I am not sure if they even have the other stuff that is needed for the project.

 

[vosadrian]

I ordered all my stuff online from an interstate Carbon Fibre supplier. I got 200gm 2X2 twill cloth, 1kg resin pack, some release film and some breather material to match (for vacuum bagging). I got some vacuum storage bags from a supermarket. Just need to get some brushes and other stuff from a hardware store and that should be all I need. This will be very much a hacked version of doing it properly, but will be interesting to see how it works out.

 

[Frito Bandito]

Can't wait to see it when it is done. Watching the process would be even better, but don't let fiddling with the camera detract from the making a good tailbox. A good idea might be to check for different hydration bladders that will allow you to position it inside the tailbox most effectively to be able to get all of the hydration out of it while seated. The one I have is alright, leaving only about 100ml left in the bag that is impossible to get out while riding. A different one has the cap and straw at the actual end of the bag which means that all of the hydration is available as long as it is tilted the right way. The only drawback is that the screw-on cap doesn't allow ice to be put it.

 

[vosadrian]

I've taken photos of what I have done so far. I plan to document it.. but if it ends up as a paper weight all bets are off!!

I have the camelbak bladder. I am not sure if it is different to yours. Mine is completely sealed, so the only way any air or water can get in or out is when you bite the valve to open the valve. So with mine you can keep sucking until you suck it inside out!! So I typically fill it and then put the lid on partially, and press it down until water starts to come out meaning the air is out, and then I tighten the lid. Then I can suck on it until I put a vaccum in it, and typically all the water is out then except a small amount in the tube. The orientation of this one does not matter. The result is the same regardless of how you oreintate the bladder.

I chose 1.5L as this is roughly 2 bidon bottles, and I have many years of riding my DF bike with 2 bottles, so it is my standard amount of water. I plan to have locations for 2 more bottles in my box also, so I will have capability to carry around 3L. That should be enough for any ride I typically do and if I do something really big, I would plan to stop for water topups.

 

[Frito Bandito]

Mine seals also, but the straw doesn't enter exactly at the bottom. I will try to remove as much of the air as possible next time to see if it helps in being able to drink all of it. I carried 1.5L for todays 90 minute ride and there was quite a bit leftover (25C temp) so I guess it'll hold me for 2 hours.

I don't know if you guys are going to believe this, but I just gave my 3 rear wheels a spin to see how well they spun while mounted on the rear of my V20. I took a video of it as well. Not the 80mm Bullet because it performed so terribly though. The 80mm Bullet with new bearings and Monokote, 25mm Schwalbe Pro One tubeless rotated 3 times before stopping. It is the wheel I used for todays ride. Since it still isn't rolling well I will pull the new bearings out and give them a look over. The tubed (with sealant) 50mm Bullet with a 25mm Schwalbe Marathon Green Guard rotated for 17 seconds on the first try and 20 seconds on the 2nd. The Scirocco with a 25mm tubed (with sealant) Michelin Power rotated for 3 minutes on the first time (accidentally lowered it and it touched the floor, but the 2nd time was 6 minutes I will upload it to Youtube in a moment and then link it here afterwards.

 

[Frito Bandito]

Here it is...

 

[Don1]

yeah baby, get them all like that

 

[Frito Bandito]

yeah baby, get them all like that

I always see videos of rear wheel spin tests to show off the ratchet sound, and those usually spin for about 2 minutes with a good wind up on the cranks, but that is the first time for me to see and do a front wheel spin test. I was expecting about a 2 minute spin as well, but 6 minutes! With a flick of the wrist? Are the ratchet pawls slowing it down that much? I don't spend a lot of time in freewheel but that seems pretty significant. But yep. I am definitely going to work on the Bullet 80, and while I am at it I will see if I can get the 50's bearings changed as well.

I should point out that that the Scirocco has Cup and Cone bearings while the Bullets have Cartridge bearings.

 

[vosadrian]

Who needs ceramic with a 6 minute spin!!

I am sure that the draggy rear wheel has cost you some CdA. It would be like riding with a slow rear tyre and increase the effective Crr. You gotta fix that!!

Something I have noticed is sealant in a tubeless tyre will slow it down on a spin down once the wheel is going slow enough that the sealant will not be pushed against the tyre and can flow in the tyre. I changed my Rovals from tubed to tubeless and the spin down time was significantly reduced. I don't think this is a factor when riding because you are going fast enough to stop the sealant flowing.

My new wheels have a noisy freehub that seems to have lots of pawls. It is much more draggy when free wheeling. If I stick the bike in fastest gear (big-small), and lift the front wheel and spin pedals backwards, the wheel starts spinning backwards from the ratchet drag quite quickly. Much more than my Rovals which would only move slowly. I am sure there is more drag when freewheeling because of this. I would not have chosen to have this free wheeling drag if I knew, but I have not noticed it slowing me down on free wheeling descents (and I am going quicker than my Rovals due to better aero). Most of the time when you are not freewheeling it of cource makes no difference. Maybe I lose 1kph freewheeling on a fast descent? Now that I know this, my next hub choice would be the one with the least pawels and quietest!

 

[Frito Bandito]

That makes sense on the sealant Adrian. And I think it doesnt have much effect while riding too.

I am not sure about Shimano but on Campagnolo it is very simple to remove 1, 2 or even all 3 of the pawls. I removed all 3 a long time ago when I hated the noise, but that was short lived. Maybe leaving one on would be a nice compromise?

Now, I like a loud freehub noise since it alerts other riders that I am there. I was even considering Chris King hubs partly for the bling factor but also because of the noise in freewheel. But for speed even while freewheeling removing the pawls might give a few seconds for those who are actually fast enough for a few seconds to be the difference.

Since new wheels might be in my future, and considering how well my Zondas with cup and cone bearings spin, Cup and Cone bearings might be a bit higher on the check list.